Intelligent molded case circuit breaker and its intelligent secondary module

Abstract

The present application relates to an intelligent molded case circuit breaker and an intelligent secondary module thereof. The intelligent secondary module is pluggable with the mechanical base of the intelligent molded case circuit breaker through a connector, and includes a signal sampling processing unit and a control unit. The control unit is connected to the signal sampling processing unit, and the control unit is connected to the memory on the mechanical base through a connector. The signal sampling processing unit is connected to the current transformer module on the mechanical base through a connector; the signal sampling processing unit is used to amplify and sample the current signal output by the current transformer module; the control unit is used to obtain the current specification data stored in the memory, and adjust the amplification factor of the signal sampling processing unit according to the current specification data, so as to achieve the uniform current specification of the intelligent secondary module, and ensure the accuracy of the overall electrical signal measurement when replacing the intelligent secondary module. When the intelligent secondary module fails, it can be replaced to reduce resource waste.

Description

Technical Field

[0001] The present application relates to the technical field of circuit breaker equipment, and in particular to an intelligent molded case circuit breaker and an intelligent secondary module thereof. Background Art

[0002] Intelligent molded case circuit breakers, also known as device-type circuit breakers, are common industrial and civil power distribution protection devices. They are suitable for environments below 2000m above sea level and can provide accurate protection against overload and short-circuit faults in distribution lines. The components of the intelligent molded case circuit breaker itself can be divided into a primary part and a secondary part: the primary part is the mechanical part such as the line current channel and the opening and closing operating mechanism; the secondary part is the electronic part such as the voltage and current sensor signal processing sampling module, CPU, display, buttons, and communication. In traditional intelligent molded case circuit breakers, the primary and secondary parts are designed as a whole, embedded and coupled with each other, and cannot be disassembled or replaced separately. Because the design service life of the mechanical part is generally more than twice that of the electronic part, and the failure rate of the mechanical part is much lower than that of the electronic part, when the electronic part is damaged or expires, the product will be scrapped as a whole because the electronic part cannot be replaced, resulting in a waste of resources. Summary of the invention

[0003] Based on this, it is necessary to provide an intelligent molded case circuit breaker and an intelligent secondary module thereof that can reduce resource waste in order to address the above problems.

[0004] An intelligent secondary module of an intelligent molded case circuit breaker is pluggable and arranged with a mechanical base of the intelligent molded case circuit breaker through a connector, and the intelligent secondary module includes a signal sampling and processing unit and a control unit;

[0005] The electronic components arranged on the mechanical base include a current transformer module and a memory; the control unit is connected to the signal sampling and processing unit, the control unit is connected to the memory on the mechanical base through the connector, and the signal sampling and processing unit is connected to the current transformer module on the mechanical base through the connector;

[0006] The signal sampling and processing unit is used to amplify and sample the current signal output by the current transformer module; the control unit is used to obtain the current specification data stored in the memory and adjust the amplification factor of the signal sampling and processing unit according to the current specification data.

[0007] In one of the embodiments, the signal sampling and processing unit includes a signal conditioning circuit and a sampling circuit, the signal conditioning circuit is connected to the current transformer module on the mechanical base through the connector, and the sampling circuit is connected to the signal conditioning circuit and the control unit;

[0008] The signal conditioning circuit amplifies the current signal output by the current transformer module, and outputs the amplified signal to the sampling circuit. The sampling circuit performs analog-to-digital conversion sampling on the amplified signal, obtains the sampling signal and sends it to the control unit. The control unit adjusts the amplification factor of the signal conditioning circuit according to the current specification data stored in the memory so that the amplified signal matches the analog-to-digital conversion range of the sampling circuit.

[0009] In one of the embodiments, the signal sampling and processing unit is a metering chip; the signal conditioning circuit uses a high-precision analog amplifier to amplify the current signal output by the current transformer module.

[0010] In one of the embodiments, the memory also stores the calibration coefficient obtained by calibrating the current transformer module, and the control unit stores the calibration coefficient obtained by calibrating the high-precision analog amplifier; the control unit is also used to synthesize the whole machine calibration coefficient based on the calibration coefficient stored in the memory and the calibration coefficient stored locally.

[0011] In one of the embodiments, the electronic components arranged on the mechanical base also include a voltage transformer, a temperature sensor and a shunt release, and the control unit is also connected to the voltage transformer, the temperature sensor and the shunt release through the connector to transmit electrical signals.

[0012] In one of the embodiments, the control unit is used to read the current specification data from the memory after power-on.

[0013] In one embodiment, the control unit reads identification information from the memory after power-on, and when determining that the intelligent secondary module is a newly replaced module based on the identification information, stores the local identification information in the memory and reads the current specification data stored in the memory.

[0014] In one of the embodiments, the control unit is also used to control the power supply of electronic components arranged on the mechanical base.

[0015] In one of the embodiments, the electronic components include at least one of a current transformer module, a memory, a voltage transformer, a temperature sensor and a shunt release.

[0016] In one of the embodiments, the intelligent secondary module further includes at least one of a display unit, a button unit, an indicator light unit, a hardware watchdog unit, a communication unit and a storage unit connected to the control unit.

[0017] In one embodiment, the intelligent secondary module also includes a three-wire power supply unit and a voltage stabilizing circuit. The three-wire power supply unit is connected to the connector and the voltage stabilizing circuit, and is used to receive a three-phase voltage and convert it into direct current and transmit it to the voltage stabilizing circuit. The voltage stabilizing circuit converts the direct current into a plurality of different supply voltages and transmits them to the corresponding units of the intelligent secondary module for power supply.

[0018] An intelligent molded case circuit breaker comprises a mechanical base, a connector, electronic components arranged on the mechanical base and the above-mentioned intelligent secondary module.

[0019] In one of the embodiments, the mechanical base is provided with a recessed cavity, the intelligent secondary module is installed in the recessed cavity, and transmits signals with the electronic components on the mechanical base through the connector.

[0020] The above-mentioned intelligent molded case circuit breaker and its intelligent secondary module, the intelligent secondary module is pluggable with the mechanical base of the intelligent molded case circuit breaker through a connector, and includes a signal sampling processing unit and a control unit. The control unit is connected to the signal sampling processing unit, the control unit is connected to the memory on the mechanical base through a connector, and the signal sampling processing unit is connected to the current transformer module on the mechanical base through a connector. The signal sampling processing unit is used to amplify and sample the current signal output by the current transformer module; the control unit is used to obtain the current specification data stored in the memory, and adjust the amplification factor of the signal sampling processing unit according to the current specification data, so as to achieve the unification of the current specification of the intelligent secondary module, and ensure the accuracy of the overall electrical signal measurement when replacing the intelligent secondary module. When the intelligent secondary module fails, it can be replaced to avoid the overall scrapping of the intelligent molded case circuit breaker and reduce resource waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A structural block diagram of a mechanical base and an intelligent secondary module of an intelligent molded case circuit breaker in one embodiment;

[0022] Figure 2 A schematic diagram of the structure of a mechanical base and an intelligent secondary module of an intelligent molded case circuit breaker in one embodiment;

[0023] Figure 3 and Figure 4 A schematic diagram of the installation of an intelligent secondary module and a mechanical base in one embodiment;

[0024] Figure 5 A front view of an intelligent secondary module in an embodiment;

[0025] Figure 6 is a side view of an intelligent secondary module in one embodiment;

[0026] Figure 7 The figure is a principle block diagram of an intelligent secondary module and a mechanical base in one embodiment. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0029] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0030] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" etc. specify the presence of stated features, wholes, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, operations, components, parts or combinations thereof.

[0031] The primary and secondary parts of the current intelligent molded case circuit breaker are designed as a whole. When the electronic part is damaged or expires, the product is scrapped as a whole because the electronic part cannot be replaced, resulting in a waste of social and economic resources. Based on this, the present application provides an intelligent molded case circuit breaker with pluggable and interchangeable intelligent secondary modules, which integrates all parts such as a signal sampling and processing unit, a display unit, a button unit, a communication unit, and a trip circuit into a separate module with an independent shell, and the module is called an intelligent secondary module (or intelligent module). The mechanical base of the circuit breaker has a recessed cavity, and the intelligent secondary module can be inserted into the base, and the signal is transmitted between the mechanical base and the intelligent module through the connector. Among them, the electronic components arranged on the mechanical base include a current transformer module and a memory, and the signal sampling and processing unit of the intelligent secondary module performs signal amplification and sampling processing on the current signal output by the current transformer module. The control unit of the intelligent secondary module obtains the current specification data stored in the memory, and adjusts the amplification factor of the signal sampling and processing unit according to the current specification data, so as to achieve the uniform current specification of the intelligent secondary module, and the accuracy of the overall electrical signal measurement can be guaranteed when the intelligent secondary module is replaced. When the intelligent secondary module fails, it can be replaced to avoid the overall scrapping of the intelligent molded case circuit breaker and reduce waste of resources.

[0032] In one embodiment, an intelligent secondary module of an intelligent molded case circuit breaker is provided, which is pluggable and removable with a mechanical base of the intelligent molded case circuit breaker through a connector, such as Figure 1 As shown, the intelligent secondary module 100 includes a signal sampling processing unit 110 and a control unit 120; the electronic components arranged on the mechanical base include a current transformer module and a memory; the control unit 120 is connected to the signal sampling processing unit 110, the control unit 120 is connected to the memory on the mechanical base through a connector, and the signal sampling processing unit 110 is connected to the current transformer module on the mechanical base through a connector. The signal sampling processing unit 110 is used to amplify and sample the current signal output by the current transformer module; the control unit 120 is used to obtain the current specification data stored in the memory, and adjust the amplification factor of the signal sampling processing unit 110 according to the current specification data. Among them, the type of the control unit 120 is not unique, and can be FPGA (Field Programmable Gate Array, field programmable logic gate array), CPU (Central Processing Unit, central processing unit), MCU (Micro Control Unit, micro control unit) or other arbitrary programmable logic devices. In this embodiment, the control unit 120 is MCU.

[0033] In one embodiment, the electronic components arranged on the mechanical base also include a voltage transformer, a temperature sensor and a shunt release, and the control unit also connects the voltage transformer, the temperature sensor and the shunt release through a connector to transmit electrical signals. Specifically, the current transformer module on the mechanical base includes a current transformer and its auxiliary circuits, and the current transformer may include a metering current transformer, a protection current transformer, etc. The electronic components arranged on the mechanical base also include components such as a voltage transformer, a temperature sensor, and a shunt release, and these electronic components are all placed in the mechanical base of the intelligent molded case circuit breaker. Voltage and current secondary signal processing and sampling, display, buttons, communication, remote signaling, opening circuit, power supply circuit, etc. are all integrated into an intelligent secondary module 100 with an independent housing. The intelligent secondary module 100 can be inserted into the mechanical base and can be easily pulled out. The intelligent secondary module 100 and the mechanical base are connected by electrical signals through a connector, and the electrical signals include secondary signals of voltage and current transformers, electrical signals of temperature sensors, electrical signals of shunt releases, etc.

[0034] In one embodiment, the control unit 120 is used to read the current specification data from the memory after power-on. Specifically, each time the intelligent secondary module 100 is powered on, the control unit 120 reads the current specification data from the memory of the mechanical base to adjust the amplification factor of the signal sampling processing unit 110 .

[0035] Further, the control unit 120 reads identification information from the memory after power-on. When it is determined that the intelligent secondary module 100 is a newly replaced module based on the identification information, the local identification information is stored in the memory, and the current specification data stored in the memory is read. After the intelligent secondary module 100 is powered on, the control unit 120 will first determine whether the intelligent secondary module 100 is a newly replaced secondary module. If it is a newly replaced secondary module, the current specification data is read from the memory of the mechanical base. Among them, the identification information can be an ID, a number, etc. In this embodiment, the identification information is an ID. Specifically, after the intelligent secondary module 100 is powered on, the control unit 120 reads the saved ID number from the memory and compares it with the local ID stored in itself. If the two are inconsistent, it means that the intelligent secondary module is a newly replaced secondary module, the local ID is written into the memory, and the current specification data is read from the memory.

[0036] In one embodiment, the signal sampling processing unit 110 includes a signal conditioning circuit 112 and a sampling circuit 114. The signal conditioning circuit 112 is connected to the current transformer module on the mechanical base through a connector, and the sampling circuit 114 is connected to the signal conditioning circuit 112 and the control unit 120. The signal conditioning circuit 112 amplifies the current signal output by the current transformer module, outputs the amplified signal to the sampling circuit 114, and the sampling circuit 114 performs analog-to-digital conversion sampling on the amplified signal to obtain a sampling signal and sends it to the control unit 120; the control unit 120 adjusts the amplification factor of the signal conditioning circuit 112 according to the current specification data stored in the memory, so that the amplified signal matches the analog-to-digital conversion range of the sampling circuit 114.

[0037] Specifically, the intelligent molded case circuit breaker is divided into specifications according to the current size, generally with specifications of different rated current levels such as 125A, 250A, 400A, 630A, etc. These specifications use different current transformers, such as Figure 2 The current transformer module may include a current transformer CT1, a rectifier bridge BD1 and a sampling resistor R1. The AC port of the rectifier bridge BD1 is connected to the current transformer CT1, the V+ port of the rectifier bridge BD1 is connected to the power supply terminal VCC, the V- port of the rectifier bridge BD1 is connected to the first end of the sampling resistor R1, and is also connected to the signal conditioning circuit 112 through a connector. The second end of the sampling resistor R1 is grounded. Due to the difference in current transformers, different sampling resistors R1 will be replaced, which results in different current signals transmitted from different mechanical bases to the intelligent secondary module 100. Therefore, by using the signal conditioning circuit 112 in the intelligent secondary module 100, the current signals of mechanical bases with different current specifications are amplified differently, so as to achieve the matching of the current signal and the analog-to-digital conversion range.

[0038] Continue to refer to Figure 2, the memory U3 on the mechanical base can be a non-volatile or volatile memory. Non-volatile memory may include read-only memory (ROM), flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). In this embodiment, the memory U3 adopts a non-volatile memory.

[0039] The signal sampling processing unit 110 is a metering chip, which includes a signal conditioning circuit 112 and a sampling circuit 114. The metering chip realizes the signal amplification and sampling functions at the same time, and outputs the sampling signal to the control unit 120. Specifically, the signal conditioning circuit 112 uses a high-precision analog amplifier to amplify the current signal output by the current transformer module. Figure 2 As shown, the high-precision analog amplifier 1122 may specifically include an amplifier U11, a resistor R2, a resistor R3, a resistor R4, a resistor R11 and a capacitor C1. The resistor R2 and the resistor R4 are connected in series, and the common end is connected to the inverting input end of the amplifier U11. The other end of the resistor R2 is connected to the V-port of the rectifier bridge BD1 through a connector to receive the current signal Ia before amplification. The other end of the resistor R4 is connected to the output end of the amplifier U11. The in-phase input end of the amplifier U11 is grounded through the resistor R3. The output end of the amplifier U11 is connected to the first end of the resistor R11. The second end of the resistor R11 is connected to the sampling circuit 114 in the metering chip and is grounded through the capacitor C1. The second end of the resistor R11 outputs the amplified current signal Ia1 to the sampling circuit 114. The metering chip sends the sampling signal obtained by analog-to-digital conversion of the internal sampling circuit 114 to the control unit 120. It can be understood that in other embodiments, the signal sampling processing unit 110 can also use two chips to respectively realize the signal amplification and sampling functions.

[0040] The high-precision analog amplifier 1122 is programmable and controllable, and the hardware does not vary due to different magnifications, so the hardware of the intelligent secondary module 100 remains consistent, and the intelligent secondary module 100 itself does not distinguish between current specifications. Different resistor networks (resistor R1) are arranged on the mechanical base according to different current specifications. Depending on the different resistor networks, the current specification data stored in the memory U3 will also be different. Once the intelligent secondary module 100 is inserted into the mechanical base, it can immediately read the current specification data stored in the memory U3 and identify the current specification of the base, so that the software controls the high-precision analog amplifier PGA to output different magnification factors. In addition, the intelligent secondary module 100 also uses the identified current specification as the whole machine current specification of the intelligent molded case circuit breaker.

[0041] Specifically, the control unit 120 will first save the ID of the intelligent secondary module 100 in the memory U3 of the mechanical base. After each power-on, the control unit 120 will read the ID information from the memory U3 to determine whether the intelligent secondary module 100 belongs to a newly replaced secondary module. For example: For example, the serial number of the first intelligent secondary module 100 is 0001, and this information is written into the memory U3 of the mechanical base after pairing. After replacing an intelligent secondary module 100 with a serial number of 0002, the control unit 120 of the intelligent secondary module 100 reads data from the memory U3 when powered on, and finds that the serial number already exists in the memory U3 and is 0001, which does not match itself. In this case, it is known that it is a newly replaced secondary module. The newly replaced intelligent secondary module 100 writes the local ID into the memory U3 on the mechanical base, and reads the current specification data stored in the memory U3 and puts it into use. It can be understood that if the ID read from the memory U3 is consistent with the local ID of the intelligent secondary module 100, it means that the intelligent secondary module 100 has not been replaced, and the intelligent secondary module 100 does not need to write the local ID into the memory U3 on the mechanical base.

[0042] In one embodiment, the memory U3 also stores the calibration coefficient obtained by calibrating the current transformer module, and the control unit 120 stores the calibration coefficient obtained by calibrating the high-precision analog amplifier PGA; the control unit 120 is also used to synthesize the calibration coefficient of the whole machine according to the calibration coefficient stored in the memory U3 and the calibration coefficient stored locally. The CT transformer and the related sampling resistor on the mechanical base, as well as the amplifier U11 and the auxiliary circuit in the intelligent secondary module 100 can be calibrated separately, and the respective calibration coefficients (including the amplitude error of the effective value of the voltage and current, the amplitude error of the reactive power, the phase error between the voltage and current, etc.) are saved separately, the parameters of the mechanical base are saved in the memory U3, and the parameters of the intelligent secondary module 100 are saved in the control unit 120. Figure 3 and Figure 4As shown, the mechanical base is provided with a recessed cavity, and the intelligent secondary module 100 is installed in the recessed cavity, and transmits signals with the electronic components on the mechanical base through the connector. That is, the intelligent secondary module 100 is inserted into the mechanical base. After the intelligent secondary module 100 is inserted into the mechanical base and the control unit 120 recognizes the valid base, it obtains the current specification and calibration coefficient of the mechanical base (the relevant parameters stored in the memory U3), and then combines the calibration coefficient of the module itself (the calibration coefficient stored by the control unit 120 itself) to synthesize the calibration coefficient of the whole machine, thereby ensuring the electrical measurement accuracy of the whole machine.

[0043] In one embodiment, the control unit 120 is also used to control the power supply of the electronic components arranged on the mechanical base. The electronic components may include at least one of a current transformer module, a memory, a voltage transformer, a temperature sensor, and a shunt release. Specifically, in order to save relevant information, there are electronic components on the mechanical base, such as Figure 2 The memory U3 in the mechanical base. In order to ensure the service life of these components, the power supply of the electronic components on the mechanical base is provided by the intelligent secondary module 100, and the intelligent secondary module 100 can control the switch of the power supply. During the normal use cycle of the intelligent molded case circuit breaker, the intelligent secondary module 100 first determines whether it is a new secondary module after powering on. If it is a new secondary module, it reads the current specification data from the memory U3 of the mechanical base. The intelligent secondary module 100 only supplies power and operates the electronic components on the mechanical base in a few time periods such as startup, and turns off the power supply for most of the other time. The electronic components on the mechanical base are almost in a non-working state, which can greatly extend their service life, thereby ensuring the service life of the entire base.

[0044] In one embodiment, the intelligent secondary module 100 further includes at least one of a display unit, a key unit, an indicator light unit, a hardware watchdog unit, a communication unit, and a storage unit connected to the control unit 120. Figure 5 and Figure 6 As shown, the display unit, the button unit, and the indicator light unit can be visually arranged on the housing of the intelligent secondary module to facilitate user operation. Figure 7As shown, the mechanical base provides power supply voltage to the intelligent secondary module 110, and transmits signals such as voltage and current sampling, temperature measurement signals, etc. The display unit can use a 128*64 dot matrix liquid crystal and is connected to the control unit 120 through IIC. The key unit can use 4 keys and is connected to the control unit 120 through GPIO. The indicator light unit can use 3-way indicator lights and is connected to the control unit 120 through GPIO. The hardware watchdog unit is connected to the control unit 120 through GPIO, and the storage unit may include an EEPROM unit and a FLASH unit. The EEPROM unit is connected to the control unit 120 through IIC, and the FLASH unit is connected to the control unit 120 through SPI. Further, the communication unit may include a Bluetooth unit, a remote signal unit, an analog input unit and an RS485 interface. The Bluetooth unit is connected to the control unit 120 through UART1, the remote signal unit is connected to the control unit 120 through GPIO, the analog input unit receives the analog signal, and converts it into a digital signal and sends it to the control unit 120, and the RS485 interface is connected to the control unit 120 through UART2.

[0045] The intelligent secondary module 100 may further include a clock chip, a topology module, a PLC module, a trip coil, an auxiliary contact, and a battery. Figure 7 The clock chip RTC is connected to the control unit 120 through IIC, the topology module is connected to the control unit 120 through GPIO, the PLC module is connected to the control unit 120 through UART3, and the trip coil and the auxiliary contact are connected to the control unit 120 through GPIO respectively.

[0046] In addition, in one embodiment, the intelligent secondary module 100 further includes a three-wire power supply unit and a voltage stabilizing circuit. The three-wire power supply unit is connected to the connector and the voltage stabilizing circuit, and is used to receive the three-phase voltage and convert it into direct current and transmit it to the voltage stabilizing circuit. The voltage stabilizing circuit converts the direct current into a variety of different power supply voltages and transmits them to the corresponding units of the intelligent secondary module for power supply. Among them, the three-wire power supply unit receives the three-phase voltage provided by the mechanical base, converts and outputs a 12V, 1A direct current voltage to the voltage stabilizing circuit, and the voltage stabilizing circuit performs voltage processing through different internal voltage stabilizers, and outputs 12V, 5V and 3.3V voltages to the corresponding units of the intelligent secondary module for power supply. It can be understood that the output voltage and current amplitude of the three-wire power supply unit and the voltage stabilizing circuit are not unique and can be adjusted according to actual needs.

[0047] In one embodiment, a smart molded case circuit breaker is provided, comprising a mechanical base, a connector, electronic components arranged on the mechanical base, and the above-mentioned smart secondary module. The mechanical base is provided with a recessed cavity, the smart secondary module is installed in the recessed cavity, and transmits signals with the electronic components on the mechanical base through the connector.

[0048] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. An intelligent secondary module of an intelligent molded case circuit breaker, characterized in that: The intelligent secondary module is pluggable through the connector and the mechanical base of the intelligent molded case circuit breaker, and includes a signal sampling and processing unit and a control unit; The electronic components arranged on the mechanical base include a current transformer module and a memory; the control unit is connected to the signal sampling and processing unit, the control unit is connected to the memory on the mechanical base through the connector, and the signal sampling and processing unit is connected to the current transformer module on the mechanical base through the connector; The signal sampling and processing unit is used to amplify and sample the current signal output by the current transformer module; the control unit is used to obtain the current specification data stored in the memory, and adjust the amplification factor of the signal sampling and processing unit according to the current specification data; The signal sampling processing unit includes a signal conditioning circuit and a sampling circuit. The signal conditioning circuit is connected to the current transformer module on the mechanical base through the connector, and the sampling circuit is connected to the signal conditioning circuit and the control unit. The signal conditioning circuit amplifies the current signal output by the current transformer module and outputs the amplified signal to the sampling circuit. The sampling circuit performs analog-to-digital conversion sampling on the amplified signal to obtain a sampling signal and sends it to the control unit. The control unit adjusts the amplification factor of the signal conditioning circuit according to the current specification data stored in the memory so that the amplified signal matches the analog-to-digital conversion range of the sampling circuit.

2. The intelligent secondary module according to claim 1, characterized in that: The signal sampling and processing unit is a metering chip; the signal conditioning circuit uses a high-precision analog amplifier to amplify the current signal output by the current transformer module.

3. The intelligent secondary module according to claim 2, characterized in that: The memory also stores the calibration coefficient obtained by calibrating the current transformer module, and the control unit stores the calibration coefficient obtained by calibrating the high-precision analog amplifier; the control unit is also used to synthesize the whole machine calibration coefficient based on the calibration coefficient stored in the memory and the calibration coefficient stored locally.

4. The intelligent secondary module according to claim 1, characterized in that: The control unit reads identification information from the memory after power-on, and when determining that the intelligent secondary module is a newly replaced module according to the identification information, stores the local identification information in the memory, and reads the current specification data stored in the memory.

5. An intelligent secondary module of an intelligent molded case circuit breaker, characterized in that: The intelligent secondary module is pluggable through the connector and the mechanical base of the intelligent molded case circuit breaker, and includes a signal sampling and processing unit and a control unit; The electronic components arranged on the mechanical base include a current transformer module and a memory; the control unit is connected to the signal sampling and processing unit, the control unit is connected to the memory on the mechanical base through the connector, and the signal sampling and processing unit is connected to the current transformer module on the mechanical base through the connector; The signal sampling and processing unit is used to amplify and sample the current signal output by the current transformer module; the control unit is used to obtain the current specification data stored in the memory, and adjust the amplification factor of the signal sampling and processing unit according to the current specification data; the control unit reads the identification information from the memory after power-on, and when it is determined that the intelligent secondary module is a newly replaced module according to the identification information, the local identification information is stored in the memory, and the current specification data stored in the memory is read.

6. The intelligent secondary module according to claim 5, characterized in that: The control unit is also used to control the power supply of electronic components arranged on the mechanical base.

7. The intelligent secondary module according to claim 6, characterized in that: The electronic components include at least one of a current transformer module, a memory, a voltage transformer, a temperature sensor and a shunt release.

8. The intelligent secondary module according to claim 6, characterized in that: It also includes a three-wire power supply unit and a voltage stabilizing circuit. The three-wire power supply unit is connected to the connector and the voltage stabilizing circuit, and is used to receive a three-phase voltage and convert it into direct current and transmit it to the voltage stabilizing circuit. The voltage stabilizing circuit converts the direct current into a variety of different power supply voltages and transmits them to the corresponding units of the intelligent secondary module for power supply.

9. The intelligent secondary module according to claim 5, characterized in that: The current transformer module includes a current transformer, a rectifier bridge and a sampling resistor. The AC port of the rectifier bridge is connected to the current transformer, the V+ port of the rectifier bridge is connected to the power supply end, the V- port of the rectifier bridge is connected to the first end of the sampling resistor, and is also connected to a signal sampling processing unit through a connector. The second end of the sampling resistor is grounded.

10. The intelligent secondary module according to claim 9, characterized in that: The signal sampling processing unit includes a signal conditioning circuit and a sampling circuit. The signal conditioning circuit is connected to the current transformer module on the mechanical base through the connector, and the sampling circuit is connected to the signal conditioning circuit and the control unit. The signal conditioning circuit amplifies the current signal output by the current transformer module and outputs the amplified signal to the sampling circuit. The sampling circuit performs analog-to-digital conversion sampling on the amplified signal to obtain a sampling signal and sends it to the control unit. The control unit adjusts the amplification factor of the signal conditioning circuit according to the current specification data stored in the memory so that the amplified signal matches the analog-to-digital conversion range of the sampling circuit.

11. An intelligent molded case circuit breaker, characterized in that: It comprises a mechanical base, a connector, electronic components arranged on the mechanical base, and the intelligent secondary module according to any one of claims 1 to 10.

12. The intelligent molded case circuit breaker according to claim 11, characterized in that: The mechanical base is provided with a recessed cavity, the intelligent secondary module can be plugged and installed in the recessed cavity, and transmits signals with the electronic components on the mechanical base through the connector.

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