Relay regulation and surge control

Abstract

A system for suppressing transient current in a circuit to prevent damage to switching devices, such as relays and / or solid state switching devices, is provided. An associated automatic transfer switch (ATS) system (300) includes a primary power line terminated to a wire cap (302) to receive power from a primary power source and an auxiliary power line terminated to a wire cap (304) to receive power from an auxiliary power source. The system (300) also includes an output (306) for connection to an output load, such as a piece of electronic equipment. The output (306) may be a female socket such that the system (300) may be directly connected to a male power port of a piece of equipment. The system (300) also includes a micro ATS module (308) operative to sense a power interruption or a signal quality degradation of a power signal of at least the primary power source and, in response, switch the power supply from the primary power source to the secondary power source. A surge suppression circuit (310) is inserted into the auxiliary power line between the module (308) and the wire cap (304).

Description

[0001] This application is a divisional application of the following patent application: Application No.: 202080033819.1, Application Date: March 12, 2020, Invention Title: Relay Conditioning and Surge Control.

[0002] Cross - References

[0003] This application claims the benefit of priority of the provisional U.S. patent application No. 62 / 817,456, titled "RELAY CONDITIONING AND POWERSURGE CONTROL", filed on March 12, 2019 (the "parent application"), and claims the benefit of priority of the parent application to the maximum extent permitted by applicable laws and regulations. The parent application is incorporated herein by reference in its entirety.

[0004] Incorporated Documents

[0005] The following applications (hereinafter referred to as "incorporated documents") are incorporated herein by reference in their entirety:

[0006] 1) U.S. Provisional Patent Application No. 61 / 372,752, titled "HIGHLY PARALLEL REDUNDANT POWERDISTRIBUTION METHODS", filed on February 26, 2013;

[0007] 2) U.S. Patent Application Publication No. US - 2012 / 0181869 - A1, titled "PARALLEL REDUNDANT POWER DISTRIBUTION", published on July 19, 2012; U.S. Patent Application Serial No. 13 / 208,333, titled "PARALLELREDUNDANT POWER DISTRIBUTION", filed on August 11, 2011 (the "'333 application"), which is a non - provisional application of and claims the priority of U.S. Provisional Patent Application No. 61 / 372,752, titled "HIGHLY PARALLEL REDUNDANT POWER DISTRIBUTIONMETHODS", filed on August 11, 2010; and U.S. Provisional Patent Application No. 61 / 372,756, titled "REDUNDANT POWER DISTRIBUTION", filed on August 11, 2010,

[0008] 3) U.S. Patent No. 8,004,115, which is from U.S. Patent Application Serial No. 12 / 569,733, titled "AUTOMATIC TRANSFER SWITCH MODULE", filed on September 29, 2009. This application is a partial continuation of U.S. Patent No. 12 / 531,212, titled "AUTOMATIC TRANSFER SWITCH", filed on September 14, 2009. This U.S. patent is the U.S. national phase of PCT Application US2008 / 57140, titled "AUTOMATIC TRANSFER SWITCH MODULE", filed on March 14, 2008. This PCT application claims the priority of U.S. Provisional Application No. 60 / 894,842, titled "AUTOMATIC TRANSFER SWITCH MODULE", filed on March 14, 2007; and

[0009] 4) U.S. Patent Application Publication No. US-2012-0092811 of U.S. Patent Application Serial No. 13 / 108,824, titled "POWER DISTRIBUTION SYSTEMS AND METHODOLOGY", filed on May 16, 2011, is a continuation of U.S. Patent Application Serial No. 12 / 891,500, titled "POWER DISTRIBUTION METHODOLOGY", filed on September 27, 2010. This U.S. Patent Application Serial No. 12 / 891,500 is a partial continuation of International Patent Application No. PCT / US2009 / 038427, titled "POWER DISTRIBUTION SYSTEMS AND METHODOLOGY", filed on March 26, 2009. This international patent application claims the priority of U.S. Provisional Application No. 61 / 039,716, titled "POWER DISTRIBUTION METHODOLOGY", filed on March 26, 2008.

[0010] 5) U.S. Patent No. 8,374,729, which is from U.S. Patent Application Serial No. 12 / 569,377, titled "SMART ELECTRICAL OUTLETS AND ASSOCIATED NETWORKS", filed on September 29, 2009, and is a continuation of U.S. Patent Application Serial No. 12 / 531,226, titled "SMART ELECTICAL OUTLETS AND ASSOCIATED NETWORKS", filed on February 16, 2010. The U.S. Patent Application Serial No. 12 / 531,226 is the U.S. national stage of PCT / US2008 / 057150, titled "SMART NEMA OUTLETS AND ASSOCIATED NETWORKS", filed on March 14, 2008, which in turn claims the priority of U.S. Provisional Application No. 60 / 894,846, titled "SMART NEMA OUTLETS AND ASSOCIATED NETWORKS", filed on March 14, 2007. TECHNICAL FIELD

[0011] Embodiments of the present invention relate to the design and operation of transfer switches connected to AC-powered equipment. Such devices have many uses; we note that the uses of the present invention generally relate to power distribution circuits and to aspects of the control of the operation of circuits and / or connected automatic transfer switch (ATS) devices. The present invention also applies to the design and operation of power distribution equipment, such as manual or automatic transfer switches (ATS), and particularly to equipment used in mission-critical environments (such as medical contexts, electric power utility grids) or in data centers or telecommunications environments. BACKGROUND ART

[0012] Recently, OEMAC to DC power supply manufacturers have introduced to the market power supplies (which are commonly used in electronic data processing (EDP) equipment) that have an unusually large capacitance directly across the AC main power supply to build a low-pass common-mode filter designed to capture any higher-order ringing energy entering or leaving the AC to DC power supply on the AC line. This is done to minimize costs and achieve FCC certification. In more traditional power supply design practices, a relatively small inductor is placed between a filter capacitor of matching size and the AC main power supply to control the exposure of the AC main power supply to the discharge of the capacitor applied directly across the AC main power supply. However, manufacturers of those power supplies have found it cheaper to add a relatively large capacitor across the AC main power supply and use cheaper and noisier components in the power supply, and not increase the capacity of the inductor (a more expensive component) to match the larger capacity of the filter capacitor. The drawback of this method is that, under certain conditions, the energy stored in the capacitor will discharge rapidly along the AC line and cause high transient currents.

[0013] These abnormal power supplies with excessive capacitance have capacitors that are up to 10 times or more the size of previous designs. This is not good design practice, but there are no electrical design or safety standards that regulate this design practice. Summary of the Invention

[0014] The present inventor has recognized that when transferring AC from one source to another quickly, such as in a manual or automatic transfer switch (ATS), these abnormal power supplies with excessive capacitance can cause problems. If the AC line on the primary side (side A in this example) is disconnected at or near the peak of the AC cycle, the filter capacitor will charge to that voltage. If the ATS accidentally transfers the load to the backup power source (side B in this example) and it is in the opposite half-cycle or near that half-cycle in voltage state, the capacitor on the input of the equipped load can be connected to a low-impedance voltage source with a polarity significantly opposite to the polarity it was charged to. In this case, the capacitor can be charged up to +300 volts, while the opposite voltage on the transferred source can be up to -350 volts (or vice versa); the resulting discharge can be up to 650 to 700 volts at 1 to 3 microfarads. Considering the average resistance of most loads, this would not be a problem and the energy of the current would be absorbed without damage, but the faulty side of the ATS is often connected to a low-impedance plugstrip with multiple pieces of EDP equipment on it. These pieces of EDP equipment often have the same input protection capacitor on them, thus reducing the instantaneous impedance to a very low value. Therefore, when the relay contacts or thyristors first close on the ATS connected to the power supply in question, a very high current is experienced instantaneously. Results measured recently in laboratory tests have shown that it is easy to obtain a short-duration current flow of 250 amperes or more, and this has the potential to cause liquefaction of the part of the relay contact closest to another relay contact. The transient current flow is so high that the effect across the contacts is very similar to that of an arc welder. Depending on the level and duration of the current flow and the maximum voltage level seen, this contact arcing can cause micro-welding of the relay contact points or damage to the solid-state switch assembly. Contact relays often stick when re-solidifying, thus causing false operation. The solid-state switch assembly may be damaged or experience a catastrophic failure and may actually smoke and / or catch fire.

[0015] This problem affects any relay - based or solid - state - based ATS, causing it to malfunction and / or fail. Since the ATS is not working, this can cause unexpected downtime of AC / DC power - supply equipment. If mission - critical equipment shuts down due to a power - delivery failure, then this can cause serious problems. What users can realize is that designers of EDPs and other equipment types for data - center use often assume that the power quality in the data center is well - controlled and of good quality. Therefore, using traditional methods to protect against transient power spikes is often limited and / or non - existent. Another problem with traditional methods is that they are often too large to be used in crowded data - center cabinets with limited free space and limited equipment form - factors. The present invention provides various devices and methods to increase the probability or actively prevent an ATS unit or other devices from failing due to these conditions and to meet other constraints (such as form - factor, energy efficiency, cost, etc.) commonly required in data centers and other environments.

[0016] Switching mechanisms for electrical connection are currently classified into: solid - state - based switching devices (such as triacs), which switch very fast but have the disadvantage of low efficiency, with approximately 0.5 - 2% of the power sent through them being lost as heat; and mechanical - based relays, which switch much slower but are much more efficient, with minimal heat loss. Many devices, including ATS units, use solid - state switches and / or mechanical relays with the above - mentioned advantages and disadvantages to control power. Regardless of whether the switch type is a solid - state relay or a mechanical relay, in many applications, either or both of the transfer time and efficiency are important and may be critical. There are ATS switches available on the market that use one, the other, or a combination of these two switching technologies.

[0017] A key example is the design and management of power distribution in data centers, because power supplies used in modern electronic data - processing (EDP) equipment can often tolerate only very short power interruptions. For example, the Computer and Business Equipment Manufacturers Association (CBEMA) guidelines used in power - supply design recommend a maximum outage time of 20 milliseconds or less. If the interruption time of power delivery to the power supply exceeds this time, then the running EDP equipment will stop or restart. Modern power supplies can often tolerate a maximum power - off time as low as approximately 12 - 14 milliseconds, which we have measured and observed in many past and current EPD devices.

[0018] This is a very important issue in the design of manual or automatic transfer switches (ATS) to switch between two or more power sources (e.g., due to a power failure such as a power outage or power quality issue), as well as other power distribution equipment used with EPD equipment. The number of modern devices controlled by embedded processors is now huge and growing rapidly. For various reasons (such as cost or size), many of these devices do not have dual power supplies. Programs running on these devices can incorporate algorithms that "learn" over time to improve the performance of the device. Data stored to perform this operation may not be written to a persistent data storage device. In that case, an ATS unit is typically used to ensure that the connected devices operate without any downtime. There are many other examples of devices that incorporate power where the speed and / or efficiency of the switching function is an important issue, and reducing or eliminating the vulnerability to these transient current and voltage problems would be highly beneficial.

[0019] The present invention relates to reducing or eliminating the vulnerability of certain devices, particularly automatic transfer switches, to high transient current and / or voltage events (well above the rated capacity of the relays and / or solid state switching devices used in the ATS) that can damage or destroy the connected (one or more) ATS units. In particular, the present invention relates to providing devices and methods for reducing or eliminating the vulnerability of the connected (one or more) ATS units. This can be accomplished by an external device that can be retrofitted to a deployed automatic transfer switch or by a design and / or relay adjustment method that can be integrated into the ATS structure, which reduces or eliminates the ATS's vulnerability to high transient currents and / or voltage problems.

[0020] Data center cabinets are very crowded, and thus meeting form factor and space constraints can be a very important part of the present invention. Contributing factors are that the limiting considerations in many ATS designs are that the size of the relays that can be used is limited by the requirement that the ATS switch fast enough. This means that the relay must actuate fast enough to complete the power transfer within the required time frame to keep the connected equipment operating without downtime due to an interruption in power delivery. Therefore, the relay design must have a contact gap, armature mass, and coil that meet the actuation speed requirements. This means that the relay gap needs to be small enough and the armature mass (including the size of the attached contacts) low enough to achieve the necessary actuation speed.

[0021] These desired characteristics limit the ability of the relay to absorb energy and thus limit its ability to tolerate these high transient current and / or voltage events without damage or destruction. Silicon-based switching devices also have limitations on the energy they can absorb from high transient current and / or voltage events without damage or destruction. A more complex factor is that relays and solid-state switching devices with greater tolerance to high current and / or voltage events are often larger and may therefore not be suitable for the available space in the desired application. Other solutions, such as the use of inductors, chokes, or other traditional methods of addressing inrush current, are often too large to fit into the space required for a particular application.

[0022] Some objectives of the present invention include the following:

[0023] Provide devices, designs, and methods to reduce or eliminate the vulnerability of ATS units or other vulnerable devices to high transient current and / or voltage events under the required form factor, as well as space and cost constraints. The devices, designs, and methods can be implemented as retrofit solutions for existing ATS installations and / or equipment, or as upgrades to the designs of current and future ATS equipment or other devices that can be used to reduce or eliminate this problem.

[0024] According to the present invention, these and other objectives are addressed by providing various systems, components, designs, and processes for improving ATS functionality. As discussed below, many aspects of the present invention are applicable to a variety of environments. However, the present invention has particular advantages in data center applications. In this regard, the present invention provides a significant degree of flexibility in dealing with high transient current and / or voltage problems associated with ATS unit functionality. The present invention is advantageous in designing devices for power distribution to server farms used by companies such as Google or Amazon or cloud computing providers.

[0025] According to one aspect of the present invention, there is provided a system for regulating an automatic transfer switch, comprising: a power signal generator for generating a power signal; a first output terminal and a second output terminal associated with the power signal generator for connecting a first input terminal and a second input terminal of the automatic transfer switch to apply the power signal to the automatic transfer switch, wherein the switch unit includes an electromechanical relay having a contact surface for making electrical contact between the armature of the relay and the connected circuit; and a controller associated with the power signal generator for controlling the power signal generator to apply the electrical signal to the contact surface, wherein the electrical signal is sufficient to cause a morphological change in the contact surface.

[0026] According to one aspect of the present invention, there is provided a device for powering an electrical device, comprising: a first line cap for connecting to the electrical device; a second line cap for connecting to a power supply; a power line extending between the first line cap and the second line cap; and a surge suppression circuit disposed in-line on the power line between the first line cap and the second line cap.

[0027] According to one aspect of the present invention, there is provided a system for regulating an automatic transfer switch, comprising: a power signal generator for generating a power signal; a first output and a second output associated with the power signal generator for connecting to a first input and a second input of the automatic transfer switch to apply the power signal to the automatic transfer switch, wherein the switching unit comprises an electromechanical relay having a contact surface for making electrical contact between the armature of the relay and the connected circuit; and a controller associated with the power signal generator for controlling the power signal generator to apply the electrical signal to the contact surface, wherein the electrical signal is sufficient to cause a morphological change in the contact surface.

[0028] According to one aspect of the present invention, there are provided methods and apparatus (a "utility") for suppressing transient currents in a circuit to prevent damage to switching devices such as relays and / or solid state switching devices. The utility relates to transfer switch systems such as ATSs, including a switching unit and a surge suppression circuit. The switching unit has a first input for receiving a first power signal, a second input for receiving a second power signal, and an output for providing a power signal to a connected load. Each input provides a power signal via a power line extending between the switch and a power receptacle associated with a power source. The switching unit further includes a switch for selectively connecting one of the first input and the second input to the output in accordance with the power signal state of at least one of the first power signal and the second power signal. The power suppression circuit suppresses surges at the switching unit. The circuit is disposed either between the switching unit and one of the power receptacles, or between the switching unit and the load. Thus, the transfer switch system resists switch damage associated with surges.

[0029] One or more surge suppression circuits may be associated with an automatic transfer switch system. In one embodiment, each of a first power line and a second power line includes a first end for connection to one of the power outlets, a second end for connection to a switch unit, and a surge suppression circuit deployed in-line between the first end and the second end of one of the first power line and the second power line. In the case where the switch unit is configured such that the first power source is the main power source, the surge suppression circuit may be deployed between the switch unit and the second outlet. Alternatively, the surge suppression circuit may be provided at the output end, at both input ends, at one input end and the output end, etc. The power outlet may be an outlet of one or more power strips. For example, the first power strip or the first outlet of the power strip may be associated with the first power source, and the second power strip or the second outlet of the power strip may be associated with the second power source. In this way, the first input end and the second input end of the switch unit may be connected to the first power source and the second power source. The power strip may also have a surge suppression function. In this regard, it has been found that in some cases the conventional surge suppression function of the power strip is not sufficient to protect the contact surface of the automatic transfer switch, but appropriate surge protection may be added to one or more outlets of the plug-in board (e.g., the outlet designated as the automatic transfer switch outlet of the board) according to the present invention.

[0030] The switch unit preferably operates to switch from a first state in which the first input end is connected to the output end and a second state in which the second input end is connected to the output end in response to detecting a power interruption and degradation of one of the first power signals from one of the power sources. The switch may include one or more electromechanical relays or solid-state switches. The surge suppression circuit may optionally be integrated into the switch housing.

[0031] According to another aspect of the present invention, the relay of the automatic transfer switch may be adjusted to better resist surge events. It has been found that if the contact surface is adjusted by changing the shape, texture or other morphology of the contact surface of the relay, the relay will better resist failures caused by surge events. This may be achieved by applying an electrical signal sufficient to change the contact surface morphology to the relay.

[0032] The corresponding utility involves providing a switch unit including a contact surface and applying an electrical signal to the contact surface sufficient to cause a desired change in the morphology of the contact surface. Specifically, the switch unit includes a first input terminal and a second input terminal for receiving a first power signal and a second power signal, an output terminal for providing a power signal to a connected load, and a switch for selectively connecting one of the first input terminal and the second input terminal to the output terminal according to the power signal state of at least one of the first power signal and the second power signal. The switch unit includes an electromechanical relay having a contact surface for making electrical contact between the armature of the relay and the connecting circuit. For example, the contact surface may be mounted on the armature or may be part of an electrode for making an electrical connection with the armature. The electrical signal is preferably sufficient to cause at least a partial change in the state of the contact surface. For example, a portion of the contact surface may become temporarily melted. The electrical signal may be applied directly to the contact surface or may be applied to the switch unit via the first and second input terminals. Alternatively, the contact surface may be manufactured to have a desired morphology to resist damage due to surges (e.g., by molding the contact surface into a desired morphology) or may be machined into a desired morphology.

[0033] According to yet another aspect of the present invention, a system for conditioning the contact surface of an automatic transfer switch is provided. As described above, it has been found that the contact surface can be conditioned to change the morphology of the contact surface, thereby rendering the automatic transfer switch less susceptible to damage due to electrical surges. Accordingly, a system can be provided to condition the contact surface by applying an electrical signal directly to the contact surface or to an automatic transfer switch including the contact surface.

[0034] The system includes a power signal generator, a first output terminal and a second output terminal associated with the power signal generator, and a controller. The power signal generator is operative to generate a power signal. The first output terminal and the second output terminal are adapted to be connected directly or via the automatic transfer switch to a first input terminal and a second input terminal connected to the contact surface, wherein the automatic transfer switch includes an electromechanical relay and the contact surface involves making electrical contact between the armature of the relay and the connecting circuit. The controller is associated with the power signal generator for controlling the power signal generator to apply an electrical signal to the contact surface, wherein the electrical signal is sufficient to cause a change in the morphology of the contact surface. It will be appreciated that the parameters that may be involved in this regard include the voltage of the signal, the current of the signal, the time of application of the signal, the frequency of the signal, the number of cycles during which the signal is applied, and the nature of any impedance capacitance or other electrical characteristics associated with the flow path of the signal. Additionally, when applying an appropriate signal, the material of the contact surface, the shape of the contact surface, the dimensions of the contact surface, and other characteristics of the contact surface may be considered.

[0035] The associated method involves providing an electrical signal generator, connecting the output of the electrical signal generator to the contact surface (either directly or indirectly), and controlling the electrical signal generator to apply one or more electrical signals to the contact surface that are sufficient to cause a morphological change in the contact surface. In a preferred embodiment, a series of signals or cycles of increasing power are applied to the contact surface such that earlier signals condition the contact surface to be more tolerant of later signals. The method may also include disconnecting the armature from the connected circuit at the contact surface and inspecting the contact surface to ensure that it has the desired properties to resist damage due to electrical surges.

[0036] In another aspect of the invention, a utility for powering an electrical device is provided. For example, the electrical device can be an automatic transfer switch or another device sensitive to electrical surges, such as a device including an electromechanical relay. The utility includes a first line cap for connection to the electrical device, a second line cap for connection to a power supply, a power line extending between the first and second line caps, and a surge suppression circuit disposed inline on the power line between the first and second line caps. For example, the first line cap can be a bus bar cap for mating with a male electrical port of an electrical device (e.g., an ATS unit), while the second line cap can be a male line cap for insertion into a female socket of a power supply unit (such as a power strip). As a further example, the first line cap can be connected to the output of the ATS and the second line cap can be connected to a piece of equipment. The surge suppression circuit can be disposed in a housing in the power line between the inserted line caps. The housing is preferably relatively small, for example having a maximum dimension not exceeding about 6 cm and a volume not exceeding about 50 cm 3 。 BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To better understand the invention and its further advantages, reference is now made to the following detailed description in conjunction with the accompanying drawings, in which:

[0038] The present disclosure is described in conjunction with the accompanying drawings:

[0039] Figure 1 An example of an operating environment of an ATS that may include a surge suppression circuit in accordance with the present invention is shown.

[0040] Figure 2 A possible example of a compact surge suppression circuit in accordance with the present invention is shown.

[0041] Figures 3 - 6 Examples of several possible form factors for implementing an aspect of the present invention in an external device or as part of an ATS design are shown. The Zonit Miniature Automatic Transfer Switch is used as a typical example of a very compact ATS.

[0042] Figures 7A - 7CIs a photograph showing a possible example of a surge suppression circuit in a power line according to the present invention.

[0043] Figures 8A - 8C Is a photograph of a contact surface that shares no regulation and has different numbers of regulation cycles according to the present invention.

[0044] Figure 9 Shows a possible example of a relay regulator according to the present invention that tests, times, and groups the relays being tested, as described herein.

[0045] Figures 10A - 10C Shows Figure 9 the form factor of the relay regulator.

[0046] Figure 11 Is a voltage-versus-time graph illustrating a surge condition solved according to the present invention.

[0047] Figure 12 Shows the voltage and current graphs corresponding to Figure 11 ...

[0048] Figure 13 Is a schematic diagram of an ATS that can be used with a surge suppression circuit according to the present invention.

[0049] Figures 14 - 16 Is a schematic diagram illustrating the operation of an external surge suppression circuit according to the present invention.

[0050] Figures 17 - 19 Is a schematic diagram illustrating the operation of an internal surge suppression circuit according to the present invention.

[0051] In the drawings, similar components and / or features may have the same reference numerals. Additionally, various components of the same type may be distinguished by following a first (e.g., numerical) label with a second (e.g., letter) label that differentiates between the similar components. If only the first reference numeral is used in the specification, then the description applies to any one of the similar components having the same first reference numeral, regardless of whether the second reference numeral is present. Detailed Description

[0052] This section describes methods for constructing multiple circuits in multiple devices such as power lines, ATS devices, or other devices. Many examples relate to a compact ATS unit. While this is considered an important use case, it should be recognized that the present invention applies to a variety of other environments. Thus, the following description should be understood as exemplary and not restrictive.

[0053] In one example, in combination with the power lines associated with an ATS, the surge circuit of the present invention can be implemented in-line in a very small form factor. This has several advantages, which are detailed below. One point to note is that depending on the design of a given ATS unit, the in-line surge circuit can be placed on the output of the ATS unit or on one or both of the power inputs. This is because an ATS designed to and / or set to use the "A" side as the preferred and primary power source only requires the power line on the "B side" input (auxiliary power) to have surge protection. Most ATS devices have a preferred power source, i.e., the "A" primary source. An ATS developed by Zonit Structural Solutions (Zonit) in Boulder, Colorado, allows the user to select which source to use as the primary source and change the primary source as desired. If the "A" source is available and optionally has sufficient quality for some designs that measure power quality, the ATS will use the "A" source. Once the "A" power drops far enough and long enough, the ATS transfer from the "A side" to the "B side" is completed. The normal definition is that a power quality disturbance can last up to 4 milliseconds, after which it becomes a power outage. Thus, most ATS units monitor the "A" side power and then switch to the "B" side power as soon as possible after 4 milliseconds.

[0054] This means that if the power on the "A" side and the "B" side is out of phase (which is very common in modern data centers using two hot phases for 208V power distribution or three-phase power distribution (which has become the most common method due to increased power ratings on the rack)), then the difference in voltage levels between the power sources can cause high transient currents and / or voltage surges in the above scenario. Therefore, it should be noted that this difference in voltage levels can be due to the difference between the voltages, or due to the difference between the voltage charged by one of the signals and the voltage of another signal in the signals, rather than due to a surge in one of the signals. Thus, the surge protection circuit in one or both of the power lines does not solve this problem. When transferring from the "B side" to the "A side", this is not a problem. This is true because when performing the transfer from the "B side" to the "A side", both sides are already powered on and operating and may have sufficient quality. In this case, the ATS can time the transfer to occur at the zero crossing of the "A" side power being transferred to, so high transient current and / or voltage events generally do not occur.

[0055] The following Figure 1 shows the operating environment of the ATS (in this case, a form factor of a micro ATS developed by Zonit). Thereafter, examples of surge suppression or surge control circuits and various form factors and alternative implementations will be described.

[0056] Figure 1 An exemplary diagram showing the application of the automatic transfer switch 50 is shown. The equipment 26 can be installed in the rack 25, which has a main wiring board 21 and an auxiliary wiring board 22 mounted on opposite sides of the rack 25. It will be appreciated that the sockets associated with the main and auxiliary power supplies can alternatively be provided in a single patch panel, provided from a rack-mounted power supply unit, or provided by other means. The shown wiring boards 21 and 22 respectively include a plurality of sockets 23 and 24. The main and auxiliary input plugs 5, 6 of the module 4 can be inserted into the sockets 23, 24 respectively, and the output socket 7 of the module 4 can be coupled to the plug 27 on the equipment 26. In normal use, this application can be replicated for multiple pieces of equipment installed in the rack 25. In operation, the equipment 26 can receive power from the main wiring board 21 through the main input line 1 and the output line 3. When an interruption of the voltage on the main wiring board 21 occurs, the automatic transfer switch 50 can then couple the equipment 26 to the auxiliary wiring board 22 through the auxiliary input line 2 and the output line 3. In this way, power redundancy is provided for the equipment 26.

[0057] The automatic transfer switch 50 can be particularly suitable for high-density applications where the rack 25 can contain forty or more pieces of equipment. For example, in such a case, forty automatic transfer switches 50 may be required with eighty input plugs 5, 6 and forty output receptacles 7. Generally, such density requires careful attention to wire management to prevent air flow blockages that may inhibit the cooling of the equipment installed in the rack 25. Thus, in such applications, the automatic transfer switch 50 reduces this problem by including wires of a length suitable for the particular application.

[0058] The various form factors (dimensions and shapes) of the ATS unit are described below. In the end view and side view, the shape of the shown module 4 is substantially rectangular, with one of the output line 3 and the input line 2 attached to one end of the module 4, and the other input line 1 attached to the opposite end. Moreover, the cross-sectional area of the module 4 can be less than about 3 square inches (not exceeding about 1.75 inches for each axis), and more preferably, less than about 2 square inches, and the length of the module 4 can be less than 5 inches, with the overall volume contained within the module 4 less than 10 cubic inches, and more preferably, less than about 7 cubic inches.

[0059] A significant feature of this embodiment of the automatic transfer switch 50 is that the relay 12 does not require any additional control circuitry to operate. The absence of a relay control circuit allows the automatic transfer switch functionality to be incorporated in a much smaller space than that required for a switch with complex circuitry (e.g., high-speed controllers, optical isolators, current sensors, synchronization circuits, etc.). The use of a DPDT relay (or a matched plurality of relays) ensures break-before-make connections, preventing the paralleling of two power sources, which can cause damage to the equipment. The automatic transfer switch 50 operates the equipment during the short time interval (e.g., a few milliseconds) between disconnecting from one source and connecting to another source by utilizing the inherent energy storage capabilities of the most common EDP equipment. In this way, the automatic transfer switch 50 provides the automatic transfer function in a smaller space and at a lower cost than traditional automatic transfer switches.

[0060] The automatic transfer switch 50 also provides switched power at the input of the equipment, thereby minimizing the probability of failure between the switch and the equipment. Additionally, the automatic transfer switch 50 occupies relatively little space, and it provides better cable management in rack-mounted equipment. The length of the wires can allow the module 4 to be placed adjacent to the rear panel of each piece of equipment and can allow connection to a patch panel without excessive wire length. This configuration eliminates the power line tangles typically associated with rack-mounted equipment. Although the automatic transfer switch is shown positioned between a piece of equipment and a patch panel or other power receptacle, it should be recognized that the automatic transfer switch can alternatively or additionally be located at other positions in the power distribution topology. For example, the switch can be located in a standard duplex receptacle, a dual power patch panel, upstream of a pair of single power patch panels, in a unified power distribution (UPD) module, upstream of a pair of UPD modules, or otherwise associated with a leaf, branch, or root of the power distribution system topology. Additionally, the switch can be used in combination with an interleaved UPD module as described in PCT application PCT / US2009 / 038427, titled "Power Distribution Systems and Methodology", which claims the priority of U.S. Provisional Application 61 / 039,716, both of which are incorporated herein by reference, to provide further options for avoiding power delivery interruptions. Some advantages of the power line in-line surge control method are listed below. See Figures 3 - 6 for some example instances that illustrate details of where the circuitry can be used in an environment of a micro ATS implemented between equipment and a patch panel.

[0061] 1. Surge Circuit – A sample circuit design, nicknamed "ZCrush", shown in Figure 1 can be placed in any desired location in the power topology in a variety of forms.

[0062] a. As an additional power line or power module (the surge circuit is placed in a metal or plastic molded housing, which is shaped according to the needs of the application and is as small as possible;

[0063] it can be connected in-line at the desired location in the power path via a connector, (one or more) hardwired connections, or a plug and receptacle or any combination of these components as required by the application. This is a convenient implementation for retrofitting existing ATS deployments.

[0064] b. As one or two input power lines of the ATS unit. For units with input receptacles, this is a convenient implementation for retrofitting existing ATS deployments.

[0065] c. As the output power line of the ATS unit.

[0066] d. As the connecting power line between the ATS unit with an output receptacle and the powered device. The Zonit locked power line technology incorporated by reference above makes many of these options easy to implement in a safe manner.

[0067] 2. It can be integrated into a strain relief device, such as the Zonit Micro ATS "Y" cable model strain relief.

[0068] 3. It can be integrated into the case of a small form factor ATS unit, such as the Zonit Micro ATS or the Zonit Mini ATS in any Mini-ATS instance.

[0069] 4. It can be used anywhere in the power path where high transient current and / or voltage events need to be controlled. Compared with larger and bulkier traditional solutions, its small form factor makes it easier to be used as an integrated solution (inside the device housing) or an external solution (outside the housing).

[0070] This is a key advantage, while traditional methods are not suitable for the required space.

[0071] 5. It can be integrated into the circuit of the ATS by adding a transient surge circuit to the design of the ATS. This can be achieved by adding it to the existing PCB layout, or it can be implemented as a separate daughter board, which is connected and installed according to the needs of a specific application. The latter method may be desirable because it has the least impact on regulatory bodies (such as Underwriters Laboratories certification).

[0072] In another example, the ATS can be designed to be less susceptible to transient currents and / or voltage surges. Example designs are shown in the incorporated documents mentioned above. This design uses a combination of relay and silicon switch methods to eliminate the problems described in the incorporated documents.

[0073] Figure 2 The surge suppression circuit limits the current experienced at the contact surface, even in the above surge scenarios. This can be achieved by limiting the voltage experienced at the contact surface (e.g., by controlling the voltage on one or both power lines or the relative voltage) or by ensuring sufficient impedance during critical time periods. Figure 2 The circuit ensures a resistance that limits the peak current during critical times.

[0074] Figures 3 - 6 Shows various form factors of a surge suppression circuit that can be used in conjunction with an ATS or other vulnerable devices according to the present invention. Figure 3 Shows an ATS system 300 with an integrated in-line surge suppression circuit. Specifically, system 300 includes a main power line terminated in a line cap 302 for receiving power from a main power source and an auxiliary power line terminated in a line cap 304 for receiving power from an auxiliary power source. System 300 also includes an output terminal 306 for connecting to an output load (such as a piece of equipment). In the example shown, output terminal 306 is a female socket such that system 300 can be directly connected to a male power port of a piece of equipment. System 300 also includes a micro ATS module 308 that operates to sense a power interruption or degradation of the signal quality of the power signal of at least the main power source and, in response, switches the power supply from the main power source to the auxiliary power source. A surge suppression circuit 310 is inserted in the auxiliary power line between module 308 and line cap 304.

[0075] Figure 4 Shows an ATS system 400 similar to Figure 3 because it includes a main power line terminated in a line cap 402, an auxiliary power line terminated in a line cap 404, and an output terminal 406 that can be directly connected to a piece of equipment. However, in Figure 4 the embodiment, both the micro ATS module and the surge suppression circuit are provided within a housing 408. The surge suppression circuit can operate to suppress surges on the main power line, the auxiliary power line, or both. Alternatively, the surge suppression circuit can suppress surges on the output circuit.

[0076] Figure 5 The ATS system 500 of Figure 4The system is similar in that it includes a main power line terminated in a line cap 502, an auxiliary power line terminated in a line cap 504, an output terminal 506, and a housing 508 incorporating the micro ATS module and surge suppression circuitry as described above. However, the output terminal 506 is connected to the housing 508 via a power line such that the housing 508 is not directly connected to the power port of a piece of equipment.

[0077] Figure 6 FIG. shows a stand-alone surge suppression power line system 600 in accordance with the present invention. The system 600 includes a power line having a first line cap 602 at its first end and a second line cap 604 at its second end. For example, the first line cap 602 may include a female socket for connection to an input of an ATS or another piece of equipment, and the second line cap 604 may include a male plug for connection to a patch panel or other power source. The surge suppression circuitry 606 is directly plugged into the power line between the first line cap 602 and the second line cap 604. The system 600 can thus be used in a variety of contexts, including as an aftermarket product to protect an ATS (e.g., by connecting to either or both inputs of the ATS or to the output of the ATS) or another vulnerable device.

[0078] Figure 13 FIG. shows a very basic diagram of a transfer switch 1300 with which surge suppression can be used as described below. Figure 13 The reference numerals of Figures 14 - 19 continue to be used for corresponding elements in. The internal relay 1302 is shown connected to the A position. The output terminal is connected to a load 1304 which has a capacitor 1306 across the hot leads of the output terminal of the ATS 1300. A normal transfer may cause the energy stored in the capacitor 1306 to be discharged at the moment the contacts are connected to the B-side relay contacts. When the disconnection from the A side occurs, these contacts will have a voltage that may be opposite to the voltage stored in the capacitor 1306.

[0079] Figures 11 - 12Shows the relationship between these voltages and the possible effects on the output current that the relay must conduct. The current "spike" shown at time t2 is the result of the remaining positive capacitor charge starting from time t1 (when the AC voltage becomes disconnected from the input terminal). In this example, it is shown that due to the very small load resistance, the capacitor does not discharge significantly. This can be true for various reasons. In particular, the internal capacitance of the load power supply can have large energy storage capacitors that are only charged during the very peak of the AC cycle. The remaining part of the AC cycle is always at a voltage lower than the voltage stored in the internal storage capacitors of the power supply. This does not leave a path for the energy stored in the externally line-connected capacitor to discharge, so the voltage and thus the stored energy remain until the connection of the ATS to the power line occurs.

[0080] Reference Figures 14 - 16 , to prevent the current from becoming too high, or reaching a level that would cause the contacts of the ATS-based relay to become welded together, a simple surge suppression circuit 1400 or inrush limiter is used in applications where the inrush limiter is internally connected to the ATS 1300. Figure 14 Shows the ATS 1300, where the circuit 1400 is in normal operation. As shown, current flows through the ATS relay 1302 to the load 1304 and returns.

[0081] When a power failure occurs on the A side, the ATS starts by disconnecting the power from the A side source and moving the relay to the opposite input terminal (i.e., the B side power supply), as Figure 15 shown. At this time, the relay 1402 shown in the inrush limiter circuit 1400 is currently open. It is a normally open relay, or a so-called type A relay.

[0082] Figure 15 Shows the current path through the ATS 1302 to the load 1304 shortly after the transfer is completed. It should be noted that the resistor 1404 is in series with the power path located inside the inrush limiter circuit 1400. This resistor is generally very small, about 4 to 10 ohms. But it is sufficient to limit the peak current from the discharge capacitance 1306 located in the load 1304, as shown. For example, on a 120VAC circuit, the possible peak voltage is approximately 170 volts. If the AC sine wave is exactly opposite when the transfer is completed, then the peak voltage at this time can be -170 volts, and when added to the remaining voltage stored in the capacitor (up to +170 volts), the difference is 340 volts. Therefore, if a 10-ohm resistor is in series with this, the peak current is limited to 34 amperes. Various resistors can be used for specific applications, but in the case of the Zonit uATS product, we use a 10-ohm resistor for products at 15 amperes and below.

[0083] Figure 16 It shows that the inrush limiter driver circuit 1400 has completed a power delay of approximately 30 milliseconds for the inrush limiter relay 1402 and has released the relay 1402. The current now returns to flow through the contacts of the inrush limiter relay 1402 instead of flowing through the resistor 1404. This saves energy and delivers full voltage to the load 1304.

[0084] The Zonit uATS product always returns power from side B to side A at the zero-crossing voltage point of the AC cycle. See the description of the Zonit uATS in the incorporated case for clarification. Since the transfer from side B to side A occurs at the zero-crossing, the energy stored in the capacitor does not dissipate when the contacts connect the side A power supply to the load, and thus no excessive current occurs.

[0085] Figures 17 - 19 It shows a simple circuit for an application where the inrush limiter is internally connected to the ATS housing (see Figures 4 - 5 ). Figure 17 It shows an ATS with an internal circuit 1700 in normal operation. As shown, the current flows through the ATS relay 1302 to the load 1304 and returns. It returns through an additional relay 1702 that is normally closed (NC). The resistor 1704 is shown across the contacts of that relay, but it does nothing because all the current bypasses the resistor 1304 through the contacts.

[0086] When a power failure occurs on side A, the ATS starts by disconnecting the power from the side A source and moving the relay 1302 to the opposite input terminal (i.e., the side B power supply). At this time, the relay 1702 shown in the inrush limiter section at the output of the transfer relay is currently closed. It is a normally closed relay, or a so-called type B relay. At the moment when power is sent to the ATS relay to start the transfer to side B, power is also sent to the inrush limiter relay at the output of the transfer relay, causing it to start opening as well.

[0087] Figure 18Shows the current path to the load through the ATS shortly after transfer completion. Note that the resistor 1704 in series with that power path is now conducting electricity. The relay contacts across the resistor 1704 are opened simultaneously with the transfer. Thus, when power is restored to the load through the ATS contacts, the power must pass through the resistor 1704. This resistance is generally very small, about 4 to 10 ohms. But it is sufficient to limit the peak current from the discharge capacitor located in the load 1304, as shown. For example, on a 120VAC circuit, the possible peak voltage is about 170 volts. If the AC sine wave is exactly opposite when the transfer is completed, then the peak voltage at this time can be -170 volts, and when added to the remaining voltage stored in the capacitor (up to +170 volts), the difference is 340 volts. Therefore, if a 10-ohm resistor is in series with this, the peak current is limited to 34 amperes. Various resistors can be used for specific applications, but in the case of the Zonit uATS product, we use a 10-ohm resistor for products at 15 amperes and below.

[0088] Figure 19 Shows that the inrush limiter detector circuit 1700 has completed delivering power to the inrush limiter relay 1702 for approximately 30 milliseconds and has released the relay 1702. The current now returns to flow through the contacts of the inrush limiter relay 1702 instead of through the resistor 1704. This saves energy and delivers full voltage to the load.

[0089] The Zonit uATS product always returns power from side B to side A at the zero-crossing voltage point of the AC cycle. See the description of the Zonit uATS for clarification. Some products (such as the Zonit uATS Industrial) do not necessarily return power to the zero-crossing side A. Therefore, the inrush limiting function may be necessary during this half cycle. Since the inrush limiter relay is driven by any transfer of the main ATS relay, a 30-millisecond power routing through the resistor also occurs when the main ATS relay releases to restore power to side A.

[0090] Figures 7A - 7C Is a photograph showing a power line with a inline surge suppression circuit similar to that shown in Figure 6 In particular, Figure 7A Shows a perspective view of the power line on which the inline surge suppression circuit housing is mounted. Figure 7B Shows a close-up of the inline surge suppression circuit with a part of the housing removed. A ruler is also shown in the photograph to provide an indication of the size of the housing. In this case, the housing has a maximum dimension of approximately 55mm. Figure 7C Shows a close-up of the inline surge suppression circuit with a part of the housing removed (opposite to the inline surge suppression circuit in Figure 7B )

[0091] According to another aspect of the present invention, the relays used in a relay-based ATS can be designed and / or conditioned to reduce their vulnerability to transient currents and / or voltage surges and the resulting likelihood of micro-welding. The relay conditioning can be performed prior to installing the relays during ATS manufacture, or can be performed on the relays of an already manufactured ATS unit, which facilitates the application of the process in the art or as a remanufacturing process. The conditioning process can result in a significant increase in the resistance of the relay to point micro-welding, thereby allowing it to reliably tolerate transient current and / or voltage events that are 2 times or higher. An example is that for a general-purpose 2GRL relay used in, for example, a data center environment, the point micro-welding resistance can be increased from a capacitive discharge of approximately 1 microfarad to a capacitive discharge of 2 microfarads.

[0092] To condition the relay, a device is provided. Figure 9 An example relay conditioning device is shown. This device applies a specific surge signal, which can be programmed as needed to condition the relay. These surge currents form an arc across the relay contacts and cause changes in the topology and condition of the relay contacts. When exposed to high transient current and / or voltage events, these changes increase the resistance of the relay to point micro-welding. The changes to the relay contacts can be described as follows. General-purpose relays are made with optimized contact materials and shapes to give both a high actuation count service life and low resistance when the contacts close and touch. Sufficient arc resistance and contact welding are also part of the design process, but are typically considered only in relation to reasonable current and / or voltage limits that are considered suitable for the intended application. Typically, the shape of the contact is a section of a large-radius sphere. Imagine two very large beach balls touching. This means that the contacts touch each other at a single point. After sufficient use, due to mechanical deformation from the contacts hitting each other when they close, this point will become slightly flattened into a small flat area. If an arc occurs, depending on the usage history, the flat area will develop pits and become somewhat irregular.

[0093] When the contacts are new, they are typically most prone to point micro-welding. This can be understood by considering how lightning strikes the earth. If there is a high point, then lightning will generally tend to strike that point in that place. This is because that is the shortest path through a mostly uniform insulator (i.e., air). If the area where the lightning strikes has several points of the same height, then it often splits into multiple paths and strikes multiple points before hitting the ground. This reduces the maximum energy experienced by each point. This is exactly what happens when a general-purpose relay undergoes the conditioning process. Figures 8A - 8C An unused relay contact is shown ( Figure 8A ), a relay contact that has undergone 10 relay conditioning cycles on the device ( Figure 8B), and a micrograph of the relay contacts ( Figure 8C ) after 100 relay adjustment cycles on the device. The effect is to increase the number of points on the contact that are very close in height, which then spreads the arc between these points and reduces the current density at any given point, in a manner similar to that described above for lightning arc occurrence. Thus, in this case, both the shape (flattened) and the texture (roughened) are modified by the electromechanical adjustment process. This adjustment does reduce the effective life of the relay to some extent, but for ATS applications, especially in data centers with controlled power quality, the reduction is not significant. This is because the number of ATS cycles is typically very low. A typical data center only requires an ATS transfer of 3 - 24 times per year for maintenance cycles. Before the relay fails, the ATS unit generally wears out due to failures of other electrical components. The rated cycle count of a general-purpose relay is typically 100k, which indicates that in a typical data center or many other types of use, it will not be the first component to fail, even if its service life is significantly shortened due to the relay adjustment process.

[0094] It is possible to manufacture relays with contact shapes that are more resistant to point micro-welding and arcing. This can be achieved by shaping the contact area designed to touch into a flat platform with a set of high points of equal height. This can be done during the manufacture of the contact, or after manufacturing into a general spherical shape by stamping the contact into the desired shape. The contact material and plating can also be optimized to increase resistance to point micro-welding. The various methods described in the present invention allow the manufacturer of the contacts and / or the OEM ATS or other equipment manufacturers to optimize costs and contact characteristics to match the requirements of the intended application, while allowing the economical manufacture and purchase of contacts. For example, Zonit adjusts general-purpose relays due to insufficient volume, as custom contacts would be much more expensive.

[0095] Figure 9 An implementation of the relay adjustment circuit is shown. Figures 10A - 10C A photograph of the relay adjustment circuit is shown. It will be recognized that any signal source that provides a signal sufficient to produce the desired morphological change can be employed, given the specific design of the contact surface under discussion and the intended operating environment of the contact surface. The relay adjustment circuit shown and the method of operating the circuit described below have several particularly notable characteristics, which relate to optionally incrementally increasing the effective adjustment signal and sorting the relays based on response time.

[0096] If the adjustment is achieved through a series of adjustment signal cycles, then the contact surface will become increasingly more adjusted with each such cycle, as Figures 8A - 8CAs shown generally in the figure. For applications with a low failure rate (even under the worst expected surge conditions), the surge signal can simply be applied in a series of cycles, where each surge signal matches the worst conditions expected in the art. However, if the failure rate is high, then applying a signal that matches the worst expected conditions will result in an unacceptably high waste rate associated with regulation. Thus, in such cases, it can be useful to implement the regulation process as a series of signal cycles that increase the effective power, such that earlier, lower-power signal cycles have a lower probability of surface micro-welding to the points to which they adhere, and then, the higher-power signal cycles adequately condition the contact surface to withstand the maximum surges that can occur in the art.

[0097] The illustrated regulation circuit simulates the surge conditions expected in the art related to the discharge surge of a charging capacitor relative to an AC signal. In the art, the maximum expected surge conditions occur when the discharge is timed to coincide with the point on the AC signal that is 180° out of phase with the surge voltage, while a discharge event that occurs at a point on the AC signal that is nearly in phase with the surge voltage will result in a relatively harmless surge.

[0098] In terms of voltage and capacitance, the illustrated regulation circuit employs a single set of discharge parameters. In cases where a progressive increase in the power regulation signal is desired, the regulation circuit can be set to progressively change the timing related to the AC signal, from a nearly matching voltage (a phase angle considered to be 0°) to the maximum voltage difference (a phase angle considered to be 180°). It will be recognized that progressive regulation can be implemented with other circuits to apply an appropriate series of signal cycles. Moreover, specific parameters (e.g., surge voltage, capacitance, AC signal voltage, number of cycles, phase difference between cycles) involve the details of a particular application and trade-offs (e.g., between optimal regulation and useful life degradation). However, a surge voltage of 300 - 400 V (e.g., 339 V) and a capacitance of 3 microfarads relative to a 240 V AC signal have been found to be effective for conditioning the contact surface of an ATS relay for use in a typical data center environment. In the above ATS application, a progressive increase in the phase angle is considered unnecessary. Thus, the surge signal is timed to be applied at a 180° phase angle and this process (cycle) is repeated, for example, 16 times. For cases with a higher failure rate, for example, the phase angle can be increased from a small phase angle (e.g., 30°) to 180° over several cycles and then multiple cycles are performed at the 180° phase angle.

[0099] An additional feature of the present invention is a method of measuring, grading, and grouping contacts based on the transfer time of the contacts. General contacts can vary widely in their actuation times for opening or closing. This is very important in ATS designs, where the movement and sequencing of one or more relays need to be carefully controlled as part of how the ATS operates. There are a variety of ways to address this issue, some of which are described in other documents incorporated by reference. The present invention adds another method to solve this problem.

[0100] The relay actuation time variations can be so large that it is not possible to precisely control the movement of a set of relays to achieve the desired ATS transfer time. Therefore, relay sequencing is a method that allows the ATS to transfer fast enough at a lower cost to meet the expected design requirements. The ATS can be designed to not have to measure and compensate for relay actuation time variations, which saves complexity and cost.

[0101] In one example of the present invention, the relay adjustment function can be combined with the measurement of the actuation time of each individual relay. The relays can then be grouped into sets, where each relay in the set is within the desired high - low actuation time range. Another device can be provided that sequences the relays to be used in the ATS from the slowest to the fastest actuation speed. Each relay in the set used in an ATS unit can then be installed in a specific location in the ATS unit being constructed. This is because the ATS can be designed such that the relationship between the members of the set of relays it uses can benefit from this actuation speed sequencing. This can also improve relay control accuracy and thus improve the ATS transfer speed and reliability.

[0102] In another example, the relay adjustment function can be performed on relays already installed in a working ATS unit. In this case, the device is relatively simple and consists of one or more patch panels and a set of attached capacitors to generate a transient current of a desired value across the contacts of the relay when the connected ATS transfers. Additional devices (such as a current interruptor switch controlled by a signal generator that can vary the time between control signals) can be used to automate the test cycle by forcing the connected ATS to automatically switch when the power on the preferred side of the ATS is interrupted by the action of the signal generator combined with the current interruptor switch. The adjustment cycle can be repeated multiple times, depending on need and / or optimality.

[0103] The foregoing description of the present invention has been presented for purposes of illustration and description. In addition, this description is not intended to limit the present invention to the form disclosed herein. Accordingly, variations and modifications commensurate with the above teachings and the skill and knowledge of the relevant art are within the scope of the present invention. The embodiments described above are also intended to explain the best mode known for practicing the present invention and to enable other practitioners in the art to utilize the present invention in such or other embodiments and with the various modifications required for the particular applications or uses of the present invention. The appended claims are intended to be construed to include alternative embodiments insofar as is permitted by the prior art.

Claims

1. A system for regulating an automatic transfer switch, comprising: A power signal generator for generating a power signal; A first output terminal and a second output terminal associated with the power signal generator for connecting to a first input terminal and a second input terminal of the automatic transfer switch to apply the power signal to the automatic transfer switch, wherein the switch unit includes an electromechanical relay having a contact surface for making electrical contact between the armature of the relay and the connected circuit; And A controller associated with the power signal generator for controlling the power signal generator to apply the electrical signal to the contact surface, wherein the electrical signal is sufficient to cause a morphological change of the contact surface.

2. A device for supplying power to an electrical device, comprising: A first wire cap for connecting to the electrical device; A second wire cap for connecting to a power supply; A power line extending between the first wire cap and the second wire cap; And A surge suppression circuit directly deployed on the power line between the first wire cap and the second wire cap.

3. A system for regulating an automatic transfer switch, comprising: A power signal generator for generating a power signal; A first output terminal and a second output terminal associated with the power signal generator for connecting to a first input terminal and a second input terminal of the automatic transfer switch to apply the power signal to the automatic transfer switch, wherein the switch unit includes an electromechanical relay having a contact surface for making electrical contact between the armature of the relay and the connected circuit; And A controller associated with the power signal generator for controlling the power signal generator to apply the electrical signal to the contact surface, wherein the electrical signal is sufficient to cause a morphological change of the contact surface.

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