Composite Current Sensor System

Abstract

An improved current monitoring system is provided for monitoring a wide range of currents. In a control system (100), a current monitor includes two or more current sensors. At least two of the current sensors have different current measurement ranges and different current measurement sensitivities. Each current sensor can be associated with one or more current monitoring thresholds, with a time delay or time threshold corresponding to each current monitoring threshold. Each current sensor can further monitor the same current having a wide range of possible current values, and generate a signal by the current sensor when the measured current exceeds a predetermined current threshold for an amount of time exceeding the corresponding time threshold. The generated signal indicates that the measured current exceeds the predetermined current threshold for a corresponding predetermined time period.

Description

[Technical field]

[0001] The present disclosure relates generally to the field of sensor systems, and more particularly to current monitoring using a composite current sensor. [Background technology]

[0002] In many conventional current monitoring systems, one or more currents are often monitored over a wide range. To handle the large current range, high current sensors are often used. However, these high current sensors are generally not sensitive enough to accurately measure lower values ​​of current. If a current sensor with greater sensitivity were used instead, there is an increased risk of the high sensitivity current sensor becoming saturated due to high current conditions. Overall, accurately measuring a wide range of currents is often inadequate in many conventional current monitoring systems. Summary of the Invention

[0003] This Summary is provided to introduce concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claims.

[0004] Therefore, there is a need for a current monitoring system with improved accuracy and reliability over a larger current range.

[0005] Some embodiments generally relate to a current monitor having two or more current sensors. At least two of the current sensors can have different current measurement ranges and different current measurement sensitivities. Each sensor can be associated with one or more current monitoring thresholds. A time delay or time threshold can correspond to each current monitoring threshold. Each sensor can monitor the same current having a wide range of possible current values. Upon exceeding a pre-defined current threshold an amount of time that the corresponding time threshold is exceeded, a signal can be generated by the current sensor. The generated signal can indicate that the measured current has exceeded the pre-defined current threshold for a corresponding pre-defined period of time. [Brief description of the drawings]

[0006] By way of example, specific embodiments of the disclosed apparatus will now be described with reference to the accompanying drawings, in which:

[0007] FIG. 1 illustrates an exemplary power distribution and control system.

[0008] FIG. 2 illustrates an exemplary current monitoring system.

[0009] FIG. 3 shows a first perspective view of the current monitoring system shown in FIG.

[0010] FIG. 4 shows a second perspective view of the current monitoring system shown in FIG.

[0011] FIG. 5 shows a bottom view of the current monitoring system shown in FIG.

[0012] FIG. 6 shows a top view of the current monitoring system shown in FIG.

[0013] FIG. 7 illustrates an exemplary flow diagram of a method for monitoring current using two or more current sensors. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present disclosure will now be described more fully with reference to the accompanying drawings, in which preferred embodiments are shown. However, the present disclosure may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. In the drawings, like reference numerals refer to like components throughout.

[0015] 1 illustrates an example power distribution and control system 100. The power distribution and control system 100 can include a power source 102, a relay 104, a load 106, a current monitor 108, and a controller 110.

[0016] The power source 102 may be, for example, a battery. In some embodiments, the power source 102 may be an automobile battery. The loads 106 may represent electronic circuits and / or devices downstream of the power source 102. These electronic elements represented by the loads 106 may receive power from the power source 102 during normal operation of the power distribution and control system 100.

[0017] The load 106 may be coupled to the power source 102 by a relay 104. As shown in FIG. 1, the relay 104 is coupled to the power source 102, and the load 106 is coupled to the relay 104. The relay 104 may be an electromagnetic relay and / or an electrically actuated switch. The relay 104 may operate as a protective relay and / or switch. As an example, the relay 104 may operate to prevent or limit damage to the load 106 upon the occurrence of a fault condition. The fault condition may include, for example, an overvoltage or overcurrent condition on the load 106.

[0018] During normal operation, when no fault condition is detected or occurs, the relay 104 can supply power from the power source 102 to the load 106. When a fault condition is detected or occurs, the relay 104 can disconnect the load 106 from the power source 102. During such a situation, the relay 104 can interrupt the electrical connection between the load 106 and the power source 102. Thus, the relay 104 can ensure that power is supplied to the load 106 when no over-voltage or over-current condition is detected or occurs (e.g., when the relay 104 is in a closed position), and can isolate and protect the load 106 when an over-voltage or over-current condition is detected or occurs (e.g., when the relay 104 is in an open position).

[0019] A current monitor 108 may be coupled to the relay 104. The current monitor 108 may monitor and / or measure the current in the relay 104. The current monitor 108 may include two or more current sensors. The two or more current sensors of the current monitor 108 may be positioned or arranged to monitor and / or measure approximately the same current flowing from the power source 102 through the relay 104 to the load 106 (e.g., a supply current provided by the power source 102 when the relay 104 provides connectivity between the power source 102 and the load 106).

[0020] The two or more current sensors of the current monitor 108 may have different current measurement ranges and current measurement sensitivities. The current measurement range of a current sensor may be the range of current over which the current sensor can accurately detect, measure, or monitor the current. The current measurement sensitivity of a current sensor may be the level of accuracy or measurement gradation of the current sensor. As an example, one of the current sensors of the current monitor 108 may have a current measurement range of -300 amperes (A) to 300 A and a current measurement sensitivity of 1 A. Thus, in this example, the current monitor 108 may measure the current in the relay to any value between -300 A and 300 A with an accuracy of 1 A (e.g., 1 A intervals).

[0021] The two or more sensors in the current monitor 108 can determine when the current in the relay 104 exceeds one or more thresholds. Upon detecting that the current in the relay 104 exceeds a predetermined threshold, the current monitor 108 can generate a signal indicating that the threshold has been exceeded. The generated signal can be provided to the controller 110. The controller 110 can control and monitor the operation of the power distribution and control system 100. For example, the controller 110 can control the operation of the relay 104. Specifically, the controller 110 controls when the relay 104 provides an electrical connection between the power source 102 and the load 106 and when the relay 104 disconnects the load 106 from the power source 102.

[0022] The controller 110 may control the relay 104 based on receiving a signal from the current monitor 108. For example, if, upon receiving a signal from the current monitor 108, one or more current thresholds are exceeded by the current in the relay 104, the controller 110 may determine to open the relay 104 such that the load 106 is disconnected from the power source 102. In this manner, protection from an over-voltage or over-current condition may be provided to the load 106.

[0023] Alternatively or additionally, any signal generated by the current monitor 108 based on the current threshold monitoring may directly control the relay 104 (e.g., may open the relay 104) or may include an alarm signal. The alarm signal generated by the current monitor 108 may signal an alarm condition (e.g., exceeding a current threshold) directly or indirectly in an audible and / or visual manner.

[0024] In general, the current monitor 108 may generate a communication signal, a control signal, or an alarm signal, or any combination thereof. Any signal generated by the current monitor 108 may be based on detecting that the current in the relay 104 exceeds a predetermined current threshold, as previously discussed.

[0025] The communication signal generated by the current monitor 108 may be provided to another element of the power distribution and control system 100. The communication signal may include information regarding the current in the relay 104 exceeding a predetermined threshold (e.g., notification of the status of the current in the relay 104). As an example, the current monitor 108 may generate the communication signal and provide the communication signal to the controller 110. In some embodiments, the controller 110 is an engine control unit (ECU) and the current monitor 108 may provide the generated communication signal to the controller 110 via a controller area network (CAN) or a local interconnect network (LIN).

[0026] The control signal generated by the current monitor 108 may be provided to control or affect the operation of other elements of the power distribution and control system 100. As an example, the current monitor generates a control signal that regulates the operation of the relay 104 in response to a current in the relay 104 exceeding a predetermined threshold.

[0027] As described above, the alarm signal generated by the current monitor 108 may include a visual or audible signal intended to alert a user of the power distribution and control system 100 to an alarm condition (e.g., the current in the relay 104 exceeding a predetermined threshold).

[0028] In conventional power distribution and control systems, current monitors typically have a single current sensor. Generally, a single current sensor cannot effectively monitor current over a wide range of currents. For example, many of the more sensitive current sensors become saturated in high current situations, but current sensors designed for high current situations are not sensitive enough to effectively measure low currents. As a result, many conventional power distribution and control systems do not effectively monitor and adequately respond to a wide range of current levels.

[0029] In contrast, multiple current sensors may be used in the current monitor 108 of the power distribution and control system 100. For example, as described above, the current sensors may have different sensitivities, allowing current to be monitored over a larger sensitivity range (e.g., as compared to using only a single current sensor).

[0030] FIG 2 illustrates an example current monitoring system 200. The current monitoring system 200 may include a portion of a relay (e.g., relay 104) and a current monitor (e.g., current monitor 108). As shown in FIG 2, the current monitoring system 200 may include an input connection or stud 202 and an output connection or stud 204. The input stud 202 may be connected to a first portion or element of a power supply (e.g., power supply 102). The output stud 204 may be connected to a first portion or element of a load (e.g., load 106).

[0031] 2, the current monitoring system 200 may include a first fixed conductor or busbar 206 and a second fixed conductor or busbar 208. Busbar 206 may be coupled to input stud 202, and busbar 208 may be coupled to output stud 204. A movable busbar or conductor 210 may be coupled between busbar 206 and busbar 208.

[0032] The movable bus bar or contact 210 can determine electrical connectivity between the bus bars 206 and 208. During normal operation of the current monitoring system 200, current (e.g., the current of the relay 104) is provided from the input stud 202 to the bus bar 206, the movable conductor 210, the bus bar 208, and the output stud 204. When an overvoltage or overcurrent condition is detected or occurs, the movable conductor 210 can be disconnected from the bus bars 206 and 208, thereby interrupting the flow of current from the input stud 202 to the output stud 204. As an example, the movable conductor 210 can move vertically (relative to the orientation of the current monitoring system 200 as illustrated in FIG. 2) to be disconnected from the bus bars 206 and 208.

[0033] The current monitoring system 200 may further include a solenoid or coil 212. Additionally, the current monitoring system 200 may include a printed circuit board (PCB) 214 on which the component elements of the current monitoring system 200 may be mounted. The input stud 202, the output stud 204, the busbar 206, the busbar 208, the moveable conductor 210, and the solenoid may form part of a relay (e.g., the relay 104). In some embodiments, these elements may form part of a main disconnect that is coupled to a power source, such as a battery (e.g., an automobile battery).

[0034] 2, the current monitoring system 200 can include a first current sensor 216 and a second current sensor 218. The first current sensor 216 and the second current sensor 218 can be magnetic current sensors. In some embodiments, the first current sensor 216 and the second current sensor 218 can be Hall sensors.

[0035] The first current sensor 216 and the second current sensor 218 can be arranged or positioned to measure approximately the same current (e.g., relay or power supply current) flowing between the input stud 202 and the output stud 204. Specifically, the first current sensor 216 is arranged to detect and / or measure the current flowing through the bus bar 206, and the second current sensor 218 is arranged to detect and / or measure the current flowing through the bus bar 208. As shown in FIG. 2, the first current sensor 216 and the second current sensor 218 can be positioned on the same side of the PCB 214 opposite the side including the bus bars 206 and 208. The first current sensor 216 and the second current sensor 218 can be positioned the same distance away from the bus bars 206 and 208, respectively, such that the first current sensor 216 and the second current sensor 218 measure approximately the same current flowing through the bus bars 206 and 208.

[0036] The first current sensor 216 and the second current sensor 218 may be part of a current monitor (e.g., current monitor 108). As such, the current monitoring system 200 can represent all or a portion of the relay 104 and current monitor 108 as shown in FIGURE 1, but is not limited to such. That is, the relay / circuit protection elements and functions of the current monitoring system 200 and the current sensing elements and functions of the current monitoring system 200 can be separated and not combined and located on the same PCB as shown in FIGURE 2.

[0037] The first current sensor 216 and the second current sensor 218 can each have a current measurement range and a current measurement sensitivity. The current measurement range and sensitivity of the first current sensor 216 and the second current sensor 218 may be different. For example, the current measurement range and current sensitivity of the first sensor 216 can be greater than the current measurement range and current sensitivity of the second sensor 216. In one embodiment, the first current sensor 216 can have a current measurement range of -300 A to 300 A and a current sensitivity of 1 A, and the second current sensor 218 can have a current measurement range of -100 A to 100 A and a current sensitivity of 0.25 A. Thus, the first current sensor 216 and the second current sensor 218 can effectively measure the same current passing through the busbars 206 and 208 at different sensitivity levels.

[0038] The first current sensor 216 and the second current sensor 218 can each be programmed to include one or more predetermined current thresholds for monitoring. The predetermined thresholds can be within the current measurement ranges of the first and second current sensors 216 and 218, respectively. For example, the first current sensor 216 can be configured or programmed with a first current threshold within its current measurement range, and the second current sensor 218 can be configured or programmed with a second current threshold within its current measurement range. The thresholds of the first sensor 216 and the second sensor 218 can be different. The thresholds of the first and second sensors 216 and 218 can each be considered to be current set points for the current sensors 216 and 218, respectively.

[0039] Additionally, the first and second current sensors 216 and 218 can be programmed or designed to determine the amount of time that the measured current exceeds a particular current threshold. The amount or period of time associated with the particular current threshold can be considered a time delay or trigger delay. For example, the first current sensor 216 can monitor a predetermined current threshold of 250 A with an associated time delay of 15 seconds. Thus, the first current sensor 216 can determine how long the current it is detecting or measuring approximately equals or exceeds 250 A. Once the detected current approximately equals or exceeds 250 A for at least about 15 seconds, the first current sensor 216 can perform a function in response thereto. As an example, the first current sensor 216 can generate a signal indicative of the detected current exceeding a current set point or threshold for a predetermined amount of time.

[0040] Similarly, as an example, the second current sensor 218 may monitor a threshold of 75 A with an associated time delay of one minute. Thus, the second current sensor 218 may determine the time that the detected current approximately equals or exceeds 75 A. Once the detected current approximately equals or exceeds 75 A for at least one minute, the second current sensor 218 may perform a function in response thereto. As an example, the second current sensor 218 may generate a signal indicative of the detected current exceeding a current set point or threshold for a predetermined amount of time.

[0041] In the above example, the first time delay (15 seconds) corresponding to the first threshold of the first current sensor 216 is less than the second time delay (1 minute) corresponding to the second threshold of the second current sensor 218, but is not limited to such time delays. In general, the time delay associated with the threshold of a less sensitive sensor (e.g., a high current sensor) may be less than the time delay associated with the threshold of a more sensitive sensor (e.g., a low current sensor).

[0042] Particularly given the different current measurement ranges and sensitivities of the first and second current sensors 216 and 218, by associating the first and second current sensors 216 and 218 with different current thresholds and corresponding time delays, the first and second current sensors 216, 218 can more effectively monitor current conditions over a wider range of currents, over a wider range of current operating conditions, and with improved sensitivity.

[0043] One or more current thresholds or current set points for the first and second current sensors 216 and 218 may also be predetermined. Additionally, a time delay or amount of time (e.g., a time threshold) associated with each current threshold may also be predetermined. In some embodiments, for example, the time delay may be set to approximately 0 seconds such that the first current sensor 216 responds immediately (i.e., there is no time delay) to a current that exceeds the corresponding threshold.

[0044] The first and second current sensors 216 and 218 can continuously monitor and measure the current in the bus bars 206 and 208, respectively. This current measurement is continuously reported (e.g., to the controller 110) and / or stored in memory by the first and second current sensors 216 and 218. Additionally, the first and second current sensors 216 and 218 can report when a predetermined threshold is exceeded. Additionally, as described above, the first and second current sensors 216 and 218 can also report when a predetermined threshold is exceeded for a corresponding predetermined period of time.

[0045] The first and second current sensors 216, 218 may generate a signal in response to exceeding a predetermined threshold for a predetermined period of time, as described above. The signal may be a communication signal, a control signal, or an alarm signal, or any combination thereof, as described above in connection with FIG. 1. In general, the current monitoring system 200 may include any number of sensors, and the sensors may be associated with any number of current set points and corresponding time delay triggers.

[0046] 3-6 illustrate several perspectives of current monitoring system 200. For example, FIG. 3 illustrates a first perspective view of exemplary current monitoring system 200, and FIG. 4 illustrates a second perspective view of exemplary current monitoring system 200. FIGs. 3 and 4 are provided to illustrate an exemplary arrangement of input studs 202, output studs 204, bus bars 206, bus bars 208, movable conductor 210, solenoid or coil 212, and PCB 214.

[0047] 5 shows a bottom view of the current monitoring system 200. As shown in FIG 5, the first current sensor 216 and the second current sensor 218 may be attached or mounted to the bottom surface of the PCB 214. The first current sensor 216 and the second current sensor 218 may be located at the bottom where the bus bars 206 and 208 (not shown in FIG 5) are located. In this way, the first current sensor 216 and the second current sensor 218 may detect and / or measure approximately the same current because the bus bars 206 and 208 carry or conduct approximately the same current.

[0048] 6 illustrates a top view of the current monitoring system 200. FIG 6 illustrates an example arrangement of the solenoid 212, bus bar 206, bus bar 208, input studs 202, and output studs 204 on the PCB 214.

[0049] 7 shows an example flow diagram of a method for monitoring current using two or more current sensors 700. The system shown in FIG. 7 can be implemented using the power distribution and control system 100 and / or the current monitoring system 200.

[0050] In step 702, current thresholds or set points for two or more current sensors may be determined or set. Each current sensor may have a current measurement range and a current measurement sensitivity. The current measurement range and current measurement sensitivity of at least two of the current sensors may be different. One or more current thresholds may be set for each current sensor.

[0051] In step 704, a time period or time delay (or time threshold) corresponding to each current threshold for each current sensor may be determined or set.

[0052] In step 706, a response action for each current threshold-time period pairing can be determined or set for each current sensor. The response action may specify an action to occur when a predetermined current threshold is approximately exceeded for a period of time that approximately exceeds a corresponding predetermined time period for the predetermined current threshold. The response action may include generating a signal indicating that the predetermined current threshold has been exceeded for the predetermined time period. The generated signal may be an alarm signal, a communication signal, or a control signal, or any combination thereof, as described above.

[0053] At step 708, two or more current sensors monitor the current. Monitoring the current can include continuously or periodically measuring the current and can further include continuously or periodically storing or reporting the current measurements. The two or more current sensors can monitor the same current. For example, the two or more current sensors can be arranged or positioned to measure approximately the same current flowing through one or more conductors, whereby the current sensors having at least a current measurement range and sensitivity can measure a value of the same current.

[0054] A predetermined response action is performed in step 710. The predetermined response action, which may be set in step 706, may be performed when the predetermined current threshold of the current sensor exceeds approximately an amount of time corresponding to a predetermined time threshold.

[0055] In general, the current monitoring systems and methods described herein can provide improved current monitoring by using two or more current sensors with different current ranges and sensitivities so that more effective monitoring is achieved over a large current range. Current threshold monitoring and responses thereto can be provided by establishing different current set points and time thresholds for the two or more current sensors. The techniques described herein can be applied to electromechanical fuses, state of charge monitoring systems, high current monitoring systems, and other systems that benefit from monitoring a wide range of currents.

[0056] While the present disclosure refers to particular embodiments, numerous modifications, substitutions, and variations to the described embodiments are possible without departing from the scope of the present disclosure as defined in the appended claims. Accordingly, it is intended that the present disclosure not be limited to the described embodiments, but rather have its full scope as defined by the language of the claims and equivalents thereof.

[0057] The present disclosure also encompasses the following aspects. [Section 1] power supply; A relay coupled to the power supply; Relay-coupled load, where the relay couples the load to the power source when the relay is in the closed position; a current monitor coupled to the relay; and Controller coupled to current monitor and the current monitor includes a first current sensor and a second current sensor; each of the first and second current sensors measuring a current in the relay; The apparatus, wherein a first current sensor determines when the current in the relay exceeds a first current set point within a first current measurement range for a first period of time, and a second current sensor determines when the current in the relay exceeds a second current set point within a second current measurement range for a second period of time. [Section 2] Item 1. The apparatus of item 1, wherein the first current sensor has a first current measurement sensitivity and the second current sensor has a second current measurement sensitivity. [Section 3] Item 3. The device of item 2, wherein the first current measurement range is greater than the second current measurement range. [Section 4] Item 4. The apparatus of item 3, wherein the first amperometric sensitivity is greater than the second amperometric sensitivity. [Section 5] 5. The apparatus of claim 4, wherein the first period of time is less than the second period of time. [Section 6] Item 1, wherein the power source is a battery. [Section 7] Item 1, wherein the controller is an engine control unit (ECU). [Section 8] Item 1. The apparatus of item 1, wherein the first current sensor generates a first signal when a current in the relay exceeds a first current set point for a first period of time. [Section 9] Item 9. The apparatus of item 8, wherein the first signal is provided to a controller. [Section 10] 10. The apparatus of claim 9, wherein the controller opens the relay to disconnect the load from the power source upon receipt of the first signal. [Section 11] 9. The apparatus of claim 8, wherein the first signal opens a relay to disconnect power from the load. [Section 12] 9. The apparatus of claim 8, wherein the first signal includes an alarm signal indicating that a current in the relay exceeds a first current set point for a first period of time. [Section 13] 9. The apparatus of claim 8, wherein the second current sensor generates a second signal when the current in the relay exceeds a second current set point for a second period of time. [Section 14] Item 14. The apparatus of item 13, wherein the second signal is provided to a controller. [Section 15] Item 15. The apparatus of item 14, wherein the controller opens the relay to disconnect the load from the power source upon receipt of the second signal. [Section 16] Item 14. The apparatus of item 13, wherein the second signal opens the relay to disconnect the load from the power source. [Section 17] 14. The apparatus of claim 13, wherein the second signal includes an alarm signal indicating that the current in the relay exceeds the second current set point for the second period of time. [Section 18] determining a first current threshold for a first current sensor, the first current sensor having a first current measurement range and a first current measurement sensitivity; determining a second current threshold of a second current sensor, the second current sensor having a second current measurement range and a second current measurement sensitivity, the first current threshold, the first current measurement range, and the first current measurement sensitivity being greater than the second current threshold, the second current measurement range, and the second current measurement sensitivity; determining a first time period corresponding to a first current threshold of a first current sensor; determining a second time period corresponding to a second current threshold of a second current sensor, the second time period being greater than the first time period; continuously monitoring the current with a first current sensor and a second current sensor; an amount of time exceeding the first time period, generating a first signal when the current exceeds a first current threshold; generating a second signal when the current exceeds a second current threshold, the amount of time that the current exceeds the second time period; and providing at least one of the first and second signals to a controller. [Section 19] Generating the first signal further includes generating a first alarm signal indicative of an amount of time exceeding the first time period, a current exceeding a first current threshold; 20. The method of claim 18, wherein generating the second signal further comprises generating a second alarm signal indicative of the amount of time exceeding the second time period, the current exceeding the second current threshold.

Claims

1. A power distribution and control device (100), comprising: Power supply (102); an electromagnetic relay (104) coupled to a power source (102); a load (106) coupled to an electromagnetic relay (104), where the electromagnetic relay (104) includes a solenoid (212), and where the electromagnetic relay (104) couples the load (106) to the power source (102) when the electromagnetic relay (104) is in a closed position; A current monitor (108) coupled to the electromagnetic relay (104), where the current monitor (108): a first current sensor (216) measuring a current in the electromagnetic relay (104), where in response to a current in the electromagnetic relay (104) exceeding a first current threshold within a first current measurement range for a first period of time, the first current sensor (216) generates a first signal, including a communication signal, a control signal, and an alarm signal; and a second current sensor (218) measuring a current in the electromagnetic relay (104), where in response to the current in the electromagnetic relay (104) exceeding a second current threshold within a second current measurement range for a second period of time, the second current sensor (218) generates second signals including communication signals, control signals, and alarm signals, the second current measurement range being different from the first current measurement range; including; and a controller (110) coupled to the current monitor (108), where the controller (110) receives the first signal or the second signal to open the electromagnetic relay (104) to disconnect the load (106) from the power source (102); Including, a first current sensor (216) and a second current sensor (218) are disposed on opposite ends of the electromagnetic relay (104), one of the first current sensor (216) and the second current sensor (218) being indirectly coupled to one of the power source (102) and the load (106) via the electromagnetic relay (104), and the other of the first current sensor (216) and the second current sensor (218) being indirectly coupled to the other of the power source (102) and the load (106) via the electromagnetic relay (104); A power distribution and control apparatus (100) in which a communication signal generated by the current monitor (108) is provided to another element of the power distribution and control apparatus (100).

2. The apparatus of claim 1 , wherein the first current sensor (216) has a first current measurement sensitivity and the second current sensor (218) has a second current measurement sensitivity.

3. The apparatus of claim 2 , wherein the first current measurement range is greater than the second current measurement range.

4. The apparatus of claim 3 , wherein the first amperometric sensitivity is greater than the second amperometric sensitivity.

5. The apparatus of claim 1 , wherein the first period of time is less than the second period of time.

6. 1. A method for monitoring current in a power distribution and control system (100) using a first current sensor (216) and a second current sensor (218), where the power distribution and control system (100) includes an electromagnetic relay (104) having a solenoid (212), where the electromagnetic relay (104) is disposed between a power source (102) and a load (106), the method comprising: Determining a first current threshold of a first current sensor (216), where the first current sensor (216) has a first current measurement range and a first current measurement sensitivity; determining a second current threshold of a second current sensor (218), where the second current sensor (218) has a second current measurement range and a second current measurement sensitivity, the first current threshold is different from the second current threshold, the first current measurement range is different from the second current measurement range, and the first current measurement sensitivity is different from the second current measurement sensitivity; Determining a first period of time corresponding to a first current threshold of a first current sensor (216); determining a second period of time corresponding to a second current threshold of a second current sensor (218), where the second period of time is different from the first period of time; continuously monitoring the current in the power distribution and control device (100) using a first current sensor (216) and a second current sensor (218); generating a first signal, including a communication signal, a control signal, and an alarm signal, in response to a current exceeding a first current threshold for at least a first period of time; generating a second signal, including a communication signal, a control signal, and an alarm signal, in response to the current exceeding the second current threshold for at least a second period of time; and and opening an electromagnetic relay (104) in the power distribution and control device (100) in response to receiving one or more of the first and second signals by a controller (110) coupled to the first and second current sensors (216 and 218), where the electromagnetic relay (104), when open, disconnects the load (106) from the power source (102). Including, a first current sensor (216) and a second current sensor (218) are disposed on opposite ends of the electromagnetic relay (104), one of the first current sensor (216) and the second current sensor (218) being indirectly coupled to one of the power source (102) and the load (106) via the electromagnetic relay (104), and the other of the first current sensor (216) and the second current sensor (218) being indirectly coupled to the other of the power source (102) and the load (106) via the electromagnetic relay (104); The method wherein the communication signal generated by the current monitor (108) is provided to another element of the power distribution and control device (100).

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