Open-phase protection circuit
By installing a frame circuit breaker and contactor on the transmission line, a lack of phase protection circuit is designed, which solves the problem of lack of phase deficiency protection in the existing technology, and realizes low -cost motor damage protection and power distribution operation safety. Improvement.
Patent Information
- Application Number
- CN202420319530.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-21
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-02-21
AI Technical Summary
The existing frame circuit breakers lack phase protection function and cannot effectively deal with phase loss problems in modern power grid operation. The existing phase loss protection circuit is costly and needs improvement.
The lack of protection circuit including the transmission line is designed. By installing a frame circuit breaker and contactor on the A -phase, B, C phase, and N phase wire wires to achieve the detection and protection of the lack of phase.
The solution uses a simple circuit to transform, and uses dozens of yuan in contacts to increase the protection function of the frame route. It effectively avoids damage caused by lack of phase, reduces costs, and improves the safety of power distribution operations.
Smart Images
Figure CN222423212U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of machinery, in particular to a phase-loss protection circuit. Background Art
[0002] The existing frame circuit breaker (only has a pressure loss coil) has incomplete protection, only has three-stage protection or four-stage protection, no phase loss protection, and cannot adapt to the safe operation of modern power grids. In order to achieve phase loss protection, some people use complex phase loss detection electronic circuits for phase loss protection, such as the motor phase loss protection circuit disclosed in utility model patent CN2016204113376, and some people set up special phase loss protectors, such as the motor overload and phase loss protection circuit for chain electric hoists disclosed in utility model patent CN2011200022619. However, the above settings are all costly and need to be improved. Utility Model Content
[0003] In order to solve the above technical problems, the utility model proposes a phase loss protection circuit.
[0004] The purpose of the utility model is achieved through the following technical solutions:
[0005] A phase-loss protection circuit comprises a power transmission line, wherein the power transmission line comprises an A-phase wire A, a B-phase wire B, a C-phase wire C and an N-phase wire N, wherein the A-phase wire A, the B-phase wire B and the C-phase wire C are provided with a first contact QF-1 of a frame circuit breaker; a main contact KM-2 of a contactor and a voltage loss coil QF-2 of a frame circuit breaker are electrically connected in series between two of the A-phase wire A, the B-phase wire B, the C-phase wire C and the N-phase wire N in sequence, and the coil KM-1 of the contactor is electrically connected between the other two wires.
[0006] A further improvement is that when the transmission line outputs a 220V voltage, the working voltage of the undervoltage coil is 220V, and the working voltage of the contactor's coil KM-1 is AC380V; one end of the contactor's coil KM-1 is electrically connected to the B-phase wire B, and the other end is electrically connected to the C-phase wire C; one end of the undervoltage coil QF-2 of the frame circuit breaker is electrically connected to the A-phase wire A through the contactor's main contact KM-2, and the other end is electrically connected to the N-phase wire N.
[0007] As a further improvement, when the transmission line outputs a voltage of 380V, the working voltage of the undervoltage coil is 380V, the working voltage of the coil KM-1 of the contactor is AC220V, one end of the coil KM-1 of the contactor is electrically connected to the B-phase wire B, and the other end is electrically connected to the N-phase wire N; one end of the undervoltage coil QF-2 of the frame circuit breaker is electrically connected to the A-phase wire A through the main contact KM-2 of the contactor, and the other end is electrically connected to the C-phase wire C.
[0008] The beneficial effects of the utility model are:
[0009] The utility model adopts a contactor of dozens of yuan, adds a frame circuit protection function, and uses old products in a new way. It can prevent the motor from being damaged due to phase loss during long-term operation, and save the loss of several thousand or tens of thousands of yuan for a motor. The circuit transformation is simple and low-cost, and the safety of power distribution operation is improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention is further described with reference to the accompanying drawings, but the contents in the accompanying drawings do not constitute any limitation to the present invention.
[0011] Figure 1 is a circuit diagram of Example 1;
[0012] Figure 2 This is a circuit diagram of Example 2. DETAILED DESCRIPTION
[0013] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and examples.
[0014] Example 1
[0015] like Figure 1 As shown, if the voltage of the pressure-loss coil of the frame circuit breaker is AC220V, then add a contactor with a coil voltage of AC380V, connect the coil KM-1 to the B and C phases, and connect the main contact KM-2 of the contactor in series with the A phase; under normal circumstances, A, B, and C all have electricity, the contactor is energized, driving the main contact KM-2 of the contactor to be energized, and the pressure-loss coil QF-2 is energized and energized, and the frame circuit breaker can be closed and operated. If any one or both phases of B and C phases are out of power at the same time, the contactor is released, and the main contact KM-2 of the contactor is disconnected, then the A phase is disconnected, the pressure-loss coil QF-2 shall not be electrically actuated, and the frame circuit breaker trips; if the A phase is out of power, the pressure-loss coil shall not be electrically actuated, and the frame circuit breaker trips, achieving the effect of phase loss protection.
[0016] Example 2
[0017] like Figure 2As shown, if the voltage of the pressure-loss coil QF-2 with the frame circuit breaker is AC380V, then add a contactor with a coil voltage of AC220V, the coil KM-1 of the contactor is connected to B and N, and the main contact KM-2 of the contactor is connected in series to phases A and C; under normal circumstances, A, B, and C are all powered, the coil KM-1 of the contactor is energized, driving the main contact to be energized, the pressure-loss coil QF-2 is energized to be energized, and the frame circuit breaker can be closed for operation. If the B phase loses pressure, the contactor is released, the main contact KM-2 of the contactor is disconnected, and the A and C phases are disconnected, the pressure-loss coil QF-2 shall not be electrically operated, and the frame circuit breaker trips; if any one or both phases of A and C phases are out of power at the same time, the pressure-loss coil QF-2 shall not be electrically operated, and the frame circuit breaker trips, achieving the effect of phase loss protection.
[0018] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit the protection scope of the utility model. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the utility model.
Claims
1. A phase loss protection circuit, characterized in that: The invention comprises a power transmission line, wherein the power transmission line comprises an A-phase wire (A), a B-phase wire (B), a C-phase wire (C) and an N-phase wire (N), wherein the A-phase wire (A), the B-phase wire (B) and the C-phase wire (C) are provided with a first contact (QF-1) of a frame circuit breaker; a main contact (KM-2) of a contactor and a voltage loss coil (QF-2) of a frame circuit breaker are electrically connected in series between two of the A-phase wire (A), the B-phase wire (B), the C-phase wire (C) and the N-phase wire (N), and a coil (KM-1) of the contactor is electrically connected between the other two wires.
2. The phase loss protection circuit according to claim 1, characterized in that: When the transmission line outputs a voltage of 220V, the working voltage of the undervoltage coil is 220V, and the working voltage of the coil (KM-1) of the contactor is AC380V; one end of the coil (KM-1) of the contactor is electrically connected to the B-phase wire (B), and the other end is electrically connected to the C-phase wire (C); one end of the undervoltage coil (QF-2) of the frame circuit breaker is electrically connected to the A-phase wire (A) through the main contact (KM-2) of the contactor, and the other end is electrically connected to the N-phase wire (N).
3. The phase loss protection circuit according to claim 1, characterized in that: The transmission line outputs a voltage of 380V, so the working voltage of the undervoltage coil is 380V, the working voltage of the contactor's coil (KM-1) is AC220V, one end of the contactor's coil (KM-1) is electrically connected to the B-phase wire (B), and the other end is electrically connected to the N-phase wire (N); one end of the undervoltage coil (QF-2) of the frame circuit breaker is electrically connected to the A-phase wire (A) through the main contact (KM-2) of the contactor, and the other end is electrically connected to the C-phase wire (C).