Method for assigning current values ​​to corresponding voltage values, circuit arrangement and insertion

Abstract

The invention relates to a method for assigning current values ​​(i) to corresponding voltage values ​​(u) in a multiphase load circuit (L) in which electrical energy is transferred from a voltage source (100) to a motor (M) and a reversing contactor circuit (WS, Q1, Q2) connected in the load circuit (L) enables a change of direction (RotR, RotL) of the motor (M) by means of two different phase conductor arrangements (LR, LL), comprising the following steps: - Recording current values ​​(i) in phase conductors (L1, L2, L3) of the load circuit (L), viewed in the direction of electrical energy transmission, behind the reversing contactor circuit (WS, Q1, Q2), - Determining voltage values ​​(u) in the load circuit (L) by tapping at least one voltage in the load circuit (L), viewed in the direction of electrical energy transmission, before the reversing contactor circuit (WS, Q1, Q2), - Providing information about a phase conductor arrangement (LR, LL) present at the time of recording the current values ​​(i) and voltage values ​​(u); - Matching recorded current values ​​(i) to corresponding recorded voltage values ​​(u) based on the provided information.

Description

[0001] The present invention relates to a method for assigning current values ​​to corresponding voltage values, a corresponding circuit arrangement and an insert of a motor control center.

[0002] Continuous monitoring of the active power of an electrical device, such as an electric motor, can provide its operator with important information. The active power of an electric motor indicates the actual load on the motor. Excessive active power leads to increased motor wear and potentially premature motor failure. Insufficient active power can indicate that the motor is idling. For example, by monitoring changes in the active power of a pump drive over time, an impending pump dry-run can be detected early. If a minimum power input is not reached, potentially significant consequential damage can be prevented by switching off the pump drive in a timely manner.

[0003] To accurately measure the active power in a three-phase AC system (L1, L2, L3), the current signal i and the voltage signal u of each of the three phases (L1, L2, L3) must be correctly assigned and evaluated. A current and voltage sensing module is typically used to acquire these signals.

[0004] A reversing contactor circuit (either counterclockwise or clockwise) can reverse the direction of rotation of a three-phase motor by swapping two phase conductors. Since two different phase conductor arrangements exist, the correct assignment of the current signal i and the voltage signal u of the three phases L1, L2, L3 in a reversing contactor circuit requires particular care.

[0005] One possibility is to perform both current and voltage sensing upstream of the reversing contactors, viewed in the direction of electrical energy transmission to the electrical consumer, i.e., upstream of the point of phase conductor reversal.

[0006] Upstream of the reversing contactors, corresponding current and voltage values ​​must always be tapped from the same phase conductor. WO 2007 / 014 725 A1 (Phoenix Contact GmbH & Co. KG) dated February 8, 2007, describes a safety switching device 900 with a current and voltage sensing unit 930 upstream of a reversing protection circuit 100. However, current and voltage sensing upstream of the reversing contactors is often not possible due to space constraints, as there is insufficient installation space for the current and voltage sensing module, e.g., in the drawers of a Motor Control Center (MCC).

[0007] Another option is to perform current and voltage measurements downstream of the reversing contactors, in the direction of electrical power transmission to the electrical load, i.e., downstream of the point of phase reversal. Downstream of the reversing contactors, corresponding current and voltage values ​​must always be taken from the same phase conductor. However, in this circuit configuration, when the motor is off (both reversing contactors are off), it is not possible to verify voltage presence in the current path upstream of the reversing contactors by measuring the voltage. Therefore, monitoring functions that require voltage detection, such as automatic restart after a power outage, are not feasible with this configuration.

[0008] The object of the present invention is an improved circuit arrangement that enables both active power measurement and voltage monitoring in a reversing contactor circuit.

[0009] This problem is solved according to the invention by a method with the features specified in claim 1. This method is for assigning current values ​​to corresponding voltage values ​​in a multiphase load circuit. In the multiphase load circuit, electrical energy is transferred from a voltage source to a motor. Since the invention lies in the field of electrical engineering, "motor" here always refers to an electric motor. In the multiphase load circuit, a reversing contactor connected in the load circuit enables a change in the direction of rotation of the motor by means of two different phase conductor arrangements. The method includes a step in which current values ​​in phase conductors of the load circuit are detected. The current values ​​are detected downstream of the reversing contactor, viewed in the direction of electrical energy transfer.The method includes a step in which voltage values ​​in the load circuit are determined by tapping at least one voltage within the load circuit. The voltage values ​​are determined upstream of the reversing contactor circuit, viewed in the direction of electrical power transmission. A voltage in a phase conductor of the load circuit can be determined by measuring the phase conductor's potential relative to another potential, such as the potential of another phase conductor, the potential of a neutral conductor, earth potential, or another reference potential. The method includes a step in which information about the phase conductor configuration present at the time the current and voltage values ​​are determined is provided. Finally, the method includes a step in which, based on the provided information, the determined current values ​​are mapped to corresponding determined voltage values.

[0010] The task is further solved by a circuit arrangement. The circuit arrangement comprises a multiphase load circuit for transmitting electrical energy from a voltage source to a motor. The circuit arrangement includes a reversing contactor connected in the load circuit, which, through two different phase conductor arrangements, can enable a change in the direction of rotation of the motor. The circuit arrangement includes a current and voltage measuring device for acquiring current and voltage values ​​in the phase conductors of the load circuit and for assigning the acquired current values ​​to corresponding acquired voltage values. The circuit arrangement includes a data storage device for providing information about the phase conductor arrangement present at the time the current and voltage values ​​were acquired.The circuit arrangement includes a voltage tap device for tapping at least one voltage in the phase conductors of the load circuit. The circuit arrangement includes an electrical line for supplying the at least one tapped voltage to the current and voltage measuring device. In the circuit arrangement, current measurement by the current and voltage measuring device is performed downstream of the reversing contactor circuit, viewed in the direction of electrical energy transmission from the voltage source to the motor. In the circuit arrangement, voltage measurement by the voltage tap device is performed upstream of the reversing contactor circuit, viewed in the direction of electrical energy transmission from the voltage source to the motor.

[0011] The invention provides a reliable mapping of current values ​​to corresponding voltage values ​​in a multiphase load circuit, in which electrical energy is transferred from a voltage source to a motor and a reversing contactor circuit connected in the load circuit enables a change in the motor's direction of rotation by means of two different phase conductor arrangements. The invention addresses, on the one hand, the requirement that voltage sensing must take place upstream of the reversing contactors so that it is possible to verify, by measuring the voltage, whether voltage is present in the current path upstream of the reversing contactors. On the other hand, the invention addresses the requirement that, because of the voltage sensing upstream of the reversing contactors, current sensing must take place downstream of the reversing contactors, as there is insufficient installation space upstream of the reversing contactors for combined current and voltage sensing.The invention is based on the finding that the risk of confusion between the phase conductors can be eliminated by providing information about the phase conductor arrangement present at the time the current and voltage values ​​are recorded.

[0012] The invention is based on the understanding that it is advantageous to perform voltage sensing upstream of the reversing contactors: this makes it possible to verify, by measuring the voltage, whether voltage is present in the current path upstream of the reversing contactors. The invention is also based on the understanding that it is advantageous to perform current sensing downstream of the reversing contactors: sufficient installation space is available there.

[0013] Advantageous embodiments and further developments of the invention are specified in the dependent claims. The method according to the invention can also be further developed according to the dependent apparatus claims, and vice versa.

[0014] According to a preferred embodiment of the method, current values ​​are recorded in all phase conductors of the load circuit. This is technically feasible in a three-phase system with three phase conductors. The current measurement can be performed, for example, using a current transformer, a shunt resistor, a GMR sensor (GMR = Giant Magnetoresistance Effect), a Rogowski coil, or a Hall sensor.

[0015] According to a preferred embodiment of the method, voltage values ​​in the load circuit are determined by tapping the voltages in all phase conductors of the load circuit. This is technically feasible in a three-phase system with three phase conductors. A voltage in a phase conductor of the load circuit can be determined by measuring the potential of the phase conductor relative to another potential, e.g., the potential of another phase conductor of the load circuit, the potential of a neutral conductor of the load circuit, earth potential, or another reference potential.

[0016] According to a preferred embodiment of the method, information about the phase conductor arrangement present at the time the current and voltage values ​​are recorded is provided from a data memory of a computer and control unit, which determines the phase conductor arrangement by controlling the reversing contactor circuit. An advantage of this is that the computer and control unit, which serves to control the reversing contactor circuit, is itself the instance that specifies which phase conductor arrangement is present at a given time; therefore, the computer and control unit is the primary source of this information. A further advantage is that this is a simple solution.

[0017] The control unit can send this information to the current and voltage measuring device. The control unit, which controls the contactors of the reversing contactor circuit, thus informs the current and voltage measuring device which contactor of the reversing contactor circuit is connected. The current and voltage measuring device can then measure with the correct assignment of current and voltage values ​​without having to determine the actual phase sequence beforehand, which offers the following advantage: Because this information is available, the current and voltage measuring device can immediately operate internally with the correct phase sequence after the contactors of the reversing contactor circuit are connected, and no undesirable delays occur when calculating other electrical quantities such as active power.

[0018] According to a preferred embodiment of the method, a temporal analysis of the recorded current values ​​and the recorded voltage values ​​is carried out, information about a phase conductor arrangement present at the time of recording the current and voltage values ​​is extracted based on the analysis carried out, and the extracted information is temporarily stored in a data storage device from which the information is provided.It is possible that in a first phase conductor arrangement (clockwise), the voltages in the phase conductors reach their maximum in the sequence L1, L2, L3, whereas in a second phase conductor arrangement (counterclockwise), the voltages in the phase conductors reach their maximum in the sequence L3, L2, L1. In this way, a temporal analysis of the voltages allows the phase conductor arrangement present at the time of a current and voltage measurement to be determined and used for the correct assignment of the current and voltage values. The advantage here is that this is an elegant solution, even if it requires relatively high computing power. For example, the current and voltage measuring device can be designed to automatically recognize the correct assignment from the voltage and current values ​​and perform this assignment itself.

[0019] According to a preferred embodiment of the method, the active power P of the motor is calculated based on the corresponding current and voltage values: P = u · i. An advantage of this is that it ensures a correct calculation of the motor's active power.

[0020] According to a preferred embodiment of the circuit arrangement, the circuit arrangement includes a computing and control unit for calculating the active power of the motor based on the corresponding current and voltage values. An advantage of this is that the computing and control unit can ensure relatively high computing power. It is possible for the computing and control unit to extract information about the phase conductor arrangement present at the time the current and voltage values ​​are acquired, based on an analysis performed on the voltage and current values, and to temporarily store the extracted information in a data memory from which it is retrieved. It is possible for the computing and control unit to send this information to the current and voltage measuring device.

[0021] According to a preferred embodiment of the circuit arrangement, the circuit arrangement includes a circuit breaker which, viewed in the direction of electrical power transmission from the voltage source to the motor, is connected in the load circuit upstream of the reversing contactor circuit. The circuit breaker can be an MCCB (Moulded Case Circuit Breaker). An advantage of this is that the circuit breaker protects the motor against faults in the load circuit, e.g., a short circuit.

[0022] According to a preferred embodiment of the circuit arrangement, the voltage is tapped directly at the circuit breaker by the voltage tap device. It is advantageous that the circuit breaker has terminals from which the voltage can be tapped.

[0023] According to a preferred embodiment of the circuit arrangement, the current and voltage sensing module for acquiring current values ​​comprises at least one through-hole current transformer through which one phase conductor of the load circuit is routed. An advantage of this is that the through-hole current transformer enables robust, simple, and reliable current sensing.

[0024] Another preferred embodiment of the invention is a module for a motor control center, which incorporates a circuit arrangement as described above. An advantage of this is that the limited installation space of a module can be optimally utilized by the circuit arrangement according to the invention.

[0025] The invention will now be explained using several embodiment examples and the accompanying drawing.

[0026] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more easily understood through the following description of exemplary embodiments, which will be explained in more detail with reference to the drawings. The drawings are schematic and not to scale. Fig. 1 a first known circuit arrangement for assigning current values ​​to corresponding voltage values; Fig. 2 a current and voltage measuring device; Fig. 3 an alternative known circuit arrangement for assigning current values ​​to corresponding voltage values; Fig. 4 a first embodiment of the circuit arrangement; Fig. 5 an alternative design of the circuit arrangement, Fig. 6. A flowchart of the procedure; and Fig. 7 a Motor Control Center.

[0027] Fig. Figure 1 shows a first known circuit arrangement for assigning current values ​​to corresponding voltage values. The circuit arrangement has a multiphase load circuit L in which electrical energy is transferred from a voltage source 100 to a motor M. The motor M is a three-phase motor. Connected to the load circuit L, in the following order from the voltage source 100 to the motor M, are a circuit breaker CB, a current and voltage measuring device UM, and a reversing contactor circuit WS, Q1, Q2.

[0028] The circuit breaker CB, e.g. an MCCB (= Moulded Case Circuit Breaker), can interrupt the load circuit L in the event of a fault, e.g. a short circuit or an overload, in order to prevent damage.

[0029] The current and voltage measuring device UM records current and voltage values ​​in the load circuit L, which can be transmitted via a signal line 30 to a computing and control unit GG.

[0030] The load circuit L has a voltage source connection point 5 and a motor-side connection point 6, between which the reversing contactor circuit WS, Q1, Q2 is connected in the load circuit L. The reversing contactor circuit WS, Q1, Q2 enables a change in the direction of rotation RotR, RotL of the motor M: to reverse the direction of rotation, two contactors are required, a first contactor Q1 and a second contactor Q2, which swap two phase conductors in the load circuit L. Activation of the first contactor "contactor right" (clockwise rotation, forward rotation) causes the motor M to rotate clockwise RotR, and activation of the second contactor "contactor left" (counterclockwise rotation, reverse rotation) causes the motor M to rotate counterclockwise RotL.

[0031] The computing and control unit GG can, on the one hand, control the reversing contactor circuit WS, Q1, Q2 via signal lines 21, 22, i.e., cause the two contactors Q1 and Q2 to close or open, and on the other hand, correlate and further process the current and voltage values ​​received from the current and voltage measuring device UM, e.g., calculate the active power of the motor M from the current and voltage values. The computing and control unit GG can be connected to a computer network C via a signal line 31, from which it receives commands, e.g., to control the reversing contactor circuit WS, Q1, Q2, or to which it transmits data, e.g., values ​​of the calculated active power of the motor M.

[0032] Siemens AG offers the "SIMOCODE pro" motor management system. Each branch of the system consists of a basic unit, the "SIMOCODE Basic Unit," which corresponds to the GG computing and control unit, and a separate current / voltage measurement module, the "SIMOCODE Combination Current / Voltage Measuring Module," which corresponds to the UM current and voltage measuring device. The "Basic Unit" and the "Combination Current / Voltage Measuring Module" are electrically connected via a system interface and a connecting cable. They can be mounted either mechanically connected as a single unit (in series) or separately (side by side).

[0033] The in Fig. The arrangement shown in Figure 1 is advantageous for assigning current values ​​to voltage values, since both the current and voltage measurements are taken by the current and voltage measuring device UM at the same location upstream of the reversing contactor circuit WS, Q1, Q2, i.e., upstream of the phase reversal point: thus, the current and voltage values ​​measured in the respective phase conductors correspond to each other. However, the arrangement shown in Figure 1 is not suitable for this purpose. Fig. The arrangement shown is not possible in many cases due to space constraints, e.g. in the buckets or panels of a Motor Control Center (MCC).

[0034] Fig. Figure 2 illustrates how the current and voltage measuring device UM records current and voltage values ​​in the load circuit L. For this purpose, the current and voltage measuring device UM, as shown in Figure 2, has the following characteristics: Fig. Figure 2 shows, on the one hand, through-hole current transformers for current measurement, in which the phase conductors L1, L2, L3 to be measured are each passed through a cable channel 10, 14 of the current and voltage measuring device UM, where they form the primary circuit of the through-hole transformer, and on the other hand, screw terminals 11 for voltage measurement, which are electrically connected to the phase conductors L1, L2, L3 to be measured by means of an electrically conductive connection 40 for tapping the phase conductors L1, L2, L3 of the load circuit L. For processing the measured values, the current and voltage measuring device UM has a processing unit 12, to which both secondary windings 13 of the through-hole current transformers and live conductors for voltage measurement are connected.

[0035] Fig. Figure 3 shows an alternative known circuit arrangement for mapping current values ​​to corresponding voltage values. The circuit arrangement has a multiphase load circuit L in which electrical energy is transferred from an electrical power source 100 to a motor M. Connected to the load circuit L, in the following order from the electrical power source 100 to the motor M, are a circuit breaker CB, a reversing contactor circuit WS, Q1, Q2, and a current and voltage measuring device UM.

[0036] Regarding the description and functions of the electrical components of the in Fig. The alternative circuit arrangement shown in 3 refers to the figure description in Fig. 1 and Fig. Reference is made to the first circuit arrangement shown in Figure 2, which applies analogously to the alternative circuit arrangement.

[0037] The in Fig. The arrangement shown in Figure 3 is advantageous for assigning current values ​​to voltage values, since both the current and voltage measurements are taken by the current and voltage measuring device UM at the same location downstream of the reversing contactor circuit WS, Q1, Q2, i.e., downstream of the phase reversal point: thus, the current and voltage values ​​measured in the respective phase conductors correspond to each other. However, with the arrangement shown in Figure 3, the following changes may occur: Fig. In the arrangement shown in Figure 3, if both reversing contactors Q1 and Q2 are switched off (motor off), it is not checked at the current and voltage measuring device UM behind the reversing contactor circuit WS, Q1, Q2 whether a voltage from the electrical energy source 100 is present at the voltage source-side connection point 5 behind the circuit breaker CB, i.e., whether the contacts of the circuit breaker are conductive. Therefore, no information is available about the switching readiness of the circuit breaker CB, which can be a prerequisite for reconnecting the load circuit after a fault. Monitoring functions that require voltage detection, e.g., automatic restart after a power failure (automatic reconnection AWE), are thus not possible.

[0038] Fig. Figure 4 shows a circuit arrangement according to the invention for assigning current values ​​to corresponding voltage values. The circuit arrangement according to the invention is similar to the one in Fig. The circuit arrangement shown in Figure 3 is configured as follows: in the load circuit L, viewed from the electrical energy source 100 to the motor M, a power switch CB, a reversing contactor circuit WS, Q1, Q2, and a current and voltage measuring device UM are connected in the following order. In the circuit arrangement according to the invention, the current measurement is carried out in the same way as in the circuit shown in Figure 3. Fig. 3 circuit arrangement shown at the location of the current and voltage measuring device UM behind the power switch CB and the reversing contactor circuit WS, Q1, Q2.

[0039] The difference of the circuit arrangement according to the invention is as follows: Fig. 4 to the in Fig. The circuit arrangement shown in section 3 lies in the voltage measurement: while in the Fig. In the circuit arrangement shown in 3, the voltage measurement also takes place at the location of the current and voltage measuring device UM behind the power switch CB and the reversing contactor circuit WS, Q1, Q2, according to the circuit arrangement according to the invention. Fig. 4 the voltage tap point 7 between the circuit breaker CB and the reversing contactor circuit WS, Q1, Q2, i.e. at the voltage source-side connection point 5 of the load circuit L for the reversing contactor circuit WS, Q1, Q2.

[0040] The voltage is tapped between the circuit breaker CB and upstream of the reversing contactor circuit WS and transmitted via an electrically conductive connection 40 to the current and voltage measuring device UM. The phase sequence of the voltage is independent of whether the "right contactor" Q1 or the "left contactor" Q2 of the reversing contactor circuit WS is activated. The current, on the other hand, is measured downstream of the reversing contactor circuit WS. The phase sequence of the current depends on whether the "right contactor" Q1 or the "left contactor" Q2 is activated. The measured voltage and current values ​​are received and processed by the current and voltage measuring device UM and, if necessary, transmitted to the computing and control unit GG.

[0041] The tapping of voltage u and current i at different locations within the circuit arrangement is necessary so that voltage measurement can be performed even when the reversing contactor circuit WS is switched off, in order to detect whether the circuit breaker CB is switched on. The voltage u is therefore tapped between the circuit breaker CB and the reversing contactor circuit WS to provide information about the switch-on readiness of the circuit breaker CB. Although the tapping of voltage u and current i takes place on opposite sides of the reversing contactor circuit WS, and thus the correct assignment of current to voltage depends on the phase conductor arrangement generated in the reversing contactor circuit WS, a correct assignment of current values ​​to voltage values ​​can be achieved according to the invention.

[0042] According to an initial embodiment, the computing and control unit GG determines whether the phase conductors L1, L2, L3 of the load circuit L are arranged by the reversing contactor circuit WS in a first phase conductor arrangement LR, in which the direction of rotation of the motor is positive RotR (= clockwise rotation), or in a second phase conductor arrangement LL, in which the direction of rotation of the motor is negative RotL (= counterclockwise rotation). Since the computing and control unit GG controls the reversing contactor circuit WS via the signal lines 21, 22 and determines which of the two contactors Q1, Q2 should be open, and consequently, by means of the interlocking mechanism, which of the two contactors Q1, Q2 is closed, this information is stored in the computing and control unit GG, for example, in a data memory SGG of the computing and control unit GG.Using the information obtained about the currently existing phase conductor arrangement LR, LL, a correct assignment of recorded current values ​​to corresponding recorded voltage values ​​can be carried out.

[0043] A processor PGG of the computer and control unit GG, which controls contactors Q1 and Q2 of the reversing contactor circuit WS, causes the information about which contactor Q1 or Q2 is switched on to be read from the data memory SGG of the computer and control unit GG and sent via signal line 30 to the current and voltage measuring device UM. The current and voltage measuring device UM can then measure the current and voltage values ​​with the correct assignment, without having to first determine the actual phase conductor arrangement and phase sequence. This offers the advantage that, immediately after switching on one of the contactors Q1 or Q2, the device can work internally with the correct phase sequence; thus, there is no undesirable delay in the calculation of electrical quantities that depend on the current and voltage values, e.g., active power.

[0044] According to a second embodiment, the computing and control unit GG determines corresponding current and voltage values ​​from an analysis of the recorded current and voltage values, which is performed by a processor PGG of the computing and control unit GG. Both the current values ​​i in the different phase conductors L1, L2, L3 and the voltage values ​​u in the different phase conductors L1, L2, L3 exhibit a characteristic pattern over time; by analyzing the time series of current and voltage values ​​i, u, the computing and control unit GG can determine which current and voltage values ​​correspond to each other. Based on this, a correct assignment of recorded current values ​​i to corresponding recorded voltage values ​​u can be made.

[0045] It is also possible for the current and voltage measuring device UM to independently recognize the correct assignment of current and voltage values ​​and apply this assignment to the recorded current and voltage values ​​by analyzing the measured current and voltage values ​​i, u, which is carried out by a processor PUM of the current and voltage measuring device UM. It is also possible for the current and voltage measuring device UM to calculate the active power and send the results of the calculation to the computing and control unit GG via signal line 30.For example, the current and voltage measuring device UM can initially store the recorded current and voltage values ​​temporarily in a data storage device SUM of the current and voltage measuring device UM and, after the correct assignment of the current and voltage values ​​has been determined by an analysis of the current and voltage values ​​by a processor PUM of the current and voltage measuring device UM, perform a calculation of, for example, the active power of the motor.

[0046] Fig. Figure 5 shows an alternative configuration of the circuit arrangement. In contrast to the one in Fig. The design shown in section 4 is located at the [location] in Fig. In the embodiment shown in Figure 5, the voltage tap point 7 is located directly at the output terminals 8 of the circuit breaker CB. From the output terminals 8, the tapped voltage is transmitted via an electrically conductive connection 40 to the current and voltage measuring device UM.

[0047] Fig. Figure 6 shows a flowchart of the procedure for assigning current values ​​i to corresponding voltage values ​​u in a multiphase load circuit L, in which electrical energy is transferred from a voltage source 100 to a motor M and a reversing contactor circuit WS, Q1, Q2 connected in the load circuit L enables a change in the direction of rotation RotR, RotL of the motor M by means of two different phase conductor arrangements LR, LL. In a first step 61, current values ​​i are measured in phase conductors L1, L2, L3 of the load circuit L, viewed in the direction of electrical energy transmission, downstream of the reversing contactor circuit WS, Q1, Q2. In a second step 62, voltage values ​​u in the load circuit L are measured by tapping at least one voltage in the load circuit L, viewed in the direction of electrical energy transmission, upstream of the reversing contactor circuit WS, Q1, Q2.In a third step 63, information I is provided about a phase conductor arrangement WS, LR, LL present at the time the current values ​​i and voltage values ​​u are recorded. Based on the provided information I, a decision is made in the fourth step 64 as to whether the assignment is carried out in a first way 65, so that the recorded current values ​​i correspond to the recorded voltage values ​​u according to a phase conductor arrangement LR that causes the motor to run clockwise RotR, or whether the assignment is carried out in a second way 66, so that the recorded current values ​​i correspond to the recorded voltage values ​​u according to a phase conductor arrangement LL that causes the motor to run counterclockwise RotL.

[0048] Fig.Figure 7 shows a Motor Control Center 1, which consists of three metallic switch panels 1.1, 1.2, 1.3 connected to each other by connecting bolts. The switch panels 1.1, 1.2, 1.3 draw electrical energy from a common bus bar located in a busbar compartment 2 of the Motor Control Center 1. Each of the switch panels 1.1, 1.2, 1.3 has several vertically stacked slots 9. Each slot can be operated via a push-button panel 4 and opened by a slide-in lever 3. A circuit arrangement according to the invention is arranged in at least one of the slots 9 of the Motor Control Center 1. Reference symbol list 1 Motor Control Center 1.1 Control panel 1.2 Control panel 1.3 Control panel 2 busbar compartment 3 Unit Operating Handles 4 Push Button Area 5. Network-side connection point of the WS 6. Motor-side connection point of the WS 7 Voltage tap point 8 output terminals of CB 9 Withdrawable unit (drawer) 10 phase inputs from the mains side 11 Phase input from the mains side 12 processing units 13 current transformers 14 phase outputs to the motor 21 Signal line 22 Signal line 30 Signal line 31 Signal line 40 Electrically conductive connection for tapping the phase conductors of the load circuit 61 first step 62 second step 63 third step 64 fourth step 65 Assignment in a first way 66 Assignment in a second way 100 Voltage network, voltage source C Computer network CB circuit breaker GG Computing and Control Unit I Information L Load circuit L1 Phase conductor 1 L2 Phase conductor 2 L3 Phase conductor 3 LR phase conductor arrangement for clockwise rotation LL Phase conductor arrangement for clockwise rotation M electrical consumer, motor PGG processor by GG UM PUM processor Q1 Schütz right, first Schütz of the WS Q2 contactor left, second contactor of the WS SGG Data Storage from GG SUM data storage from UM UM current and voltage measuring device WS reversing contactor circuit RotR Right-hand rotation of M RotL Left rotation of M

Claims

[1] Method for assigning current values ​​(i) to corresponding voltage values ​​(u) in a multiphase load circuit (L) in which electrical energy is transferred from a voltage source (100) to a motor (M) and a reversing contactor circuit (WS, Q1, Q2) connected in the load circuit (L) enables a change of direction (RotR, RotL) of the motor (M) by means of two different phase conductor arrangements (LR, LL), comprising the following steps: - Recording current values ​​(i) in phase conductors (L1, L2, L3) of the load circuit (L), viewed in the direction of electrical energy transmission, behind the reversing contactor circuit (WS, Q1, Q2), - Determining voltage values ​​(u) in the load circuit (L) by tapping at least one voltage in the load circuit (L), viewed in the direction of electrical energy transmission, before the reversing contactor circuit (WS, Q1, Q2), - Providing information about a phase conductor arrangement (LR, LL) present at the time of recording the current values ​​(i) and voltage values ​​(u); - Matching recorded current values ​​(i) to corresponding recorded voltage values ​​(u) based on the provided information. [2] Method according to claim 1, wherein the information about a phase conductor arrangement (LR, LL) present at the time of recording the current values ​​(i) and voltage values ​​(u) is provided from a data storage device (SGG) of a computing and control unit (GG), which determines the phase conductor arrangement (LR, LL) by controlling the reversing contactor circuit (WS, Q1, Q2). [3] A method according to any of the preceding claims, comprising the following steps: - Performing a temporal analysis of the recorded current values ​​(i) and the recorded voltage values ​​(u); and - Extraction of information about a phase conductor arrangement (LR, LL) present at the time of recording the current values ​​(i) and voltage values ​​(u) based on the analysis performed; - Temporarily storing the extracted information in a data store (SUM) from which the information is provided. [4] Method according to one of the preceding claims, wherein the active power of the motor (M) is calculated on the basis of the corresponding current values ​​(i) and voltage values ​​(u). [5] Circuit arrangement comprising: - a multi-phase load circuit (L) for transferring electrical energy from a voltage source (100) to a motor (M), - a reversing contactor circuit (WS, Q1, Q2) connected in the load circuit (L), which can enable a change of direction of rotation (RotR, RotL) of the motor (M) by means of two different phase conductor arrangements (LR, LL), - a current and voltage measuring device (UM) for detecting current values ​​(i) and voltage values ​​(u) in phase conductors (L1, L2, L3) of the load circuit (L) and for assigning detected current values ​​(i) to corresponding detected voltage values ​​(u), - a data storage device (SUM, SGG) for providing information about a phase conductor arrangement (LR, LL) present at the time of recording the current values ​​(i) and voltage values ​​(u); - a voltage tap device (7, 11, 40) for tapping at least one voltage (u) in phase conductors (L1, L2, L3) of the load circuit (L); - an electrical line (40) for supplying the at least one tapped voltage (u) to the current and voltage measuring device (UM), wherein - the current measurement is carried out by the current and voltage measuring device (UM), viewed in the direction of the electrical energy transmission from the voltage source (100) to the motor (M), behind the reversing contactor circuit (WS, Q1, Q2), and - the voltage tap is made by the voltage tap device (7, 11, 40), in the direction of the electrical energy transmission from the voltage source (100) to the motor (M), before the reversing contactor circuit (WS, Q1, Q2). [6] Circuit arrangement according to claim 5, comprising - a computing and control device (GG) for calculating the active power of the motor (M) based on the corresponding current values ​​(i) and voltage values ​​(u). [7] Circuit arrangement according to one of claims 5 or 6, comprising - a circuit breaker (CB) which, viewed in the direction of electrical energy transmission from the voltage source (100) to the motor (M), is connected in the load circuit (L) before the reversing contactor circuit (WS, Q1, Q2). [8] Circuit arrangement according to claim 7, wherein the voltage tap is taken directly at the circuit breaker (CB) by the voltage tap device (7, 11, 40). [9] Circuit arrangement according to one of claims 5 to 8, wherein the current and voltage sensing module (UM) for sensing current values ​​(i) has at least one through-hole current transducer through which one phase conductor (L1, L2, L3) of the load circuit (L) is passed. [10] Insert (9) of a Motor Control Center (1) comprising a circuit arrangement according to any one of claims 5 to 9.

Images