Control circuit for overhauling draining pump

Abstract

The utility model provides a drainage pump maintenance control circuit which comprises a first power transmission line, a second power transmission line, a drainage pump maintenance control loop and a water filling valve time control loop, the maintenance drainage pump control loop comprises a manual and automatic change-over switch which is connected with a first power transmission line and can be switched to a manual or automatic control circuit, and the two circuits are both connected with a coil of a pump starting auxiliary relay and a switch static contact of a pump delay relay. A switch of the pump delay relay is provided with two movable contacts which are respectively connected with a coil of the water filling valve control relay and a coil of the pump start control relay; coils of the three relays are connected with a second power transmission line. The water filling valve time control loop comprises a pump time delay relay coil and a pump starting auxiliary relay switch which are connected in series. Switches of the water filling valve control relay and the pump starting control relay are respectively used for starting the water filling valve and the maintenance drainage pump, so that the water pump can be automatically filled and closed before and after the maintenance drainage pump is manually started.

Description

Technical Field

[0001] This application belongs to the field of electric control technology, and particularly relates to a control circuit for overhauling a drainage pump. Background Art

[0002] The overhaul drainage pump system is an important system in a hydropower plant. Its safe, reliable and stable operation is an important guarantee for the safety of the generator set, the powerhouse and the maintenance personnel. The original control methods for the overhaul drainage pump in the hydropower plant where the applicant is located are manual control method and automatic control method. The automatic control method mainly conducts direct control through a control cabinet. There are several switches in the control cabinet, and it can be controlled by a local or remote control unit. When performing manual control, before manually starting the pump, it is necessary to manually operate the water filling valve to fill water into the pump, and after the pump starts, it is necessary to manually close the water filling valve, which increases the operation steps and the labor intensity of the operator. Content of the Utility Model

[0003] The main purpose of this application is to provide a control circuit for overhauling a drainage pump to realize automatic water filling and automatic water closing for the pump before and after manual start of the overhaul drainage pump. For this purpose, the following technical solutions are adopted in this application:

[0004] A control circuit for overhauling a drainage pump includes a first power transmission line and a second power transmission line for transmitting alternating current. A manual-automatic changeover switch, a control cabinet, a pump start auxiliary relay, a pump delay relay, a water filling valve control relay, and a pump start control relay are provided between the former two to form an overhaul drainage pump control circuit and a water filling valve time control circuit;

[0005] The overhaul drainage pump control circuit includes the manual-automatic changeover switch. The manual-automatic changeover switch is connected to the first power transmission line and can be switched to a parallel manual control line and automatic control line. Both lines are connected to the coil of the pump start auxiliary relay and the static contact of the switch of the pump delay relay; the control cabinet is arranged on the automatic control line and is used to control the on-off of the line by receiving a control signal; the switch of the pump delay relay is provided with a first moving contact and a second moving contact. The static contact and the first moving contact are in a normally closed state. The first moving contact is connected to the coil of the water filling valve control relay, and the second moving contact is connected to the coil of the pump start control relay; the coils of the pump start auxiliary relay, the water filling valve control relay, and the pump start control relay are all connected to the second power transmission line;

[0006] The water filling valve time control circuit includes the coil of the pump delay relay and the switch of the pump start auxiliary relay, and the two are connected in series between the first power transmission line and the second power transmission line;

[0007] The switch of the water filling valve control relay serves as the switch to start the water filling valve, and the switch of the pump start control relay serves as the switch to start the maintenance drainage pump.

[0008] In at least one embodiment, a stop switch combination and a start switch combination are serially connected to the manual-automatic changeover switch in the control cabinet. The stop switch combination includes a remote stop switch and a local stop switch connected in series. Both the remote stop switch and the local stop switch are in a normally closed state and are respectively controlled by a remote control unit and a local control unit. The start switch combination includes a remote start switch and a local start switch connected in parallel. Both the remote start switch and the local start switch are in a normally open state and are respectively controlled by a remote control unit and a local control unit.

[0009] In at least one embodiment, a circuit breaker may be provided on the first power transmission line, and an emergency stop button may also be provided.

[0010] The maintenance drainage pump control circuit provided by this application can achieve the following beneficial effects: 1. Optimize the original control circuit of the maintenance drainage pump and make it more intelligent; 2. Realize automatic water filling and automatic water shut-off of the water pump before and after manual start of the maintenance drainage pump without manual intervention; 3. Reduce the operation steps and the labor intensity of the operator. Description of the Drawings

[0011] Now, one or more embodiments of this application will be described only by way of example with reference to the accompanying drawings, where Figure 1 is the circuit diagram of the maintenance drainage pump control circuit shown in the embodiment of this application. Detailed Description of the Embodiment

[0012] The following will describe this application in detail with reference to the exemplary embodiments in the drawings. It should be understood, however, that this application can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided herein to make the disclosure of this application more complete and to fully convey the concept of this application to those skilled in the art.

[0013] In the description of this application, it should be understood that the terms "center", "lateral", "longitudinal", "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of this application.

[0014] As Figure 1As shown in the figure, the maintenance drainage pump control circuit of the embodiment of the present application includes a first power line L and a second power line N for transmitting alternating current. A manual-automatic changeover switch ZK, a control cabinet JXK, a pump start auxiliary relay KA1, a pump delay relay KT, a water filling valve control relay KA2, and a pump start control relay KA3 are provided between the former two to at least form a maintenance drainage pump control circuit and a water filling valve time control circuit.

[0015] Among them, the first power line L is the live wire, and the second power line N is the neutral wire. The two lines are used to supply power to the maintenance drainage pump control circuit and the water filling valve time control circuit to achieve corresponding control purposes. A circuit breaker QF and an emergency stop button SBE are provided on the first power line L to ensure line safety and cut off the power supply in case of emergency.

[0016] The maintenance drainage pump control circuit includes a manual-automatic changeover switch ZK, which is connected to the first power line L and can be switched to a parallel manual control line and an automatic control line. Both lines are connected to the coil of the pump start auxiliary relay KA1 and the static contact of the switch of the pump delay relay KT; the control cabinet JXK is arranged on the automatic control line to control the on-off of the line by receiving control signals; the switch of the pump delay relay KT has a first moving contact and a second moving contact. The static contact and the first moving contact are in a normally closed state. The first moving contact is connected to the coil of the water filling valve control relay KA2, and the second moving contact is connected to the coil of the pump start control relay KA3; the coils of the pump start auxiliary relay KA1, the water filling valve control relay KA2, and the pump start control relay KA3 are all connected to the second power line L. The water filling valve time control circuit includes the coil of the pump delay relay KT and the switch of the pump start auxiliary relay KA1, and the two are connected in series between the first power line L and the second power line N.

[0017] The switch of the water filling valve control relay KA2 serves as the switch to start the water filling valve; that is, this switch forms a water filling circuit with the water filling valve. The switch of the pump start control relay KA3 serves as the switch to start the maintenance drainage pump; that is, this switch forms a pump water circuit with the maintenance drainage pump. The water filling valve and the maintenance drainage pump can be connected to the first power line L and the second power line N; however, considering that the first and second power lines mainly output alternating current for control and their voltage is relatively small, the water filling valve and the maintenance drainage pump (especially the maintenance drainage pump) may require a relatively higher voltage power supply as power, so the water filling valve and the maintenance drainage pump can also use other power sources.

[0018] The control circuit of the maintenance drainage pump in the embodiment of the present application mainly adds a pump start auxiliary relay KA1, a pump delay relay KT, and a water filling valve control relay KA2 on the basis of the original circuit. When the manual-automatic changeover switch ZK is switched to the manual mode, the automatic control circuit is disconnected, the coil of the pump start auxiliary relay KA1 is energized to trigger its switch to close, so that the coil of the pump delay relay KT is energized and enters the delay state. In this state, the coil of the water filling valve control relay KA2 is energized to trigger its switch to close, and then the water filling valve is started to fill water into the maintenance drainage pump. After the delay time of the pump delay relay KT reaches the set time (this time can be preset or adjusted according to the water filling situation of the water filling valve), the switch of the pump start auxiliary relay KA1 is switched from the first moving contact to the second moving contact, thereby disconnecting the water filling valve control relay KA2 and connecting the coil of the pump start control relay KA3. After this coil is energized, it triggers the switch of the pump start control relay KA3 to close, and finally the maintenance drainage pump is started.

[0019] Continue to refer to Figure 1 , a stop switch combination and a start switch combination are sequentially connected in series to the manual-automatic changeover switch ZK in the control cabinet JXK; the stop switch combination includes a remotely controlled stop switch K01 and a local stop switch KO2 connected in series. Both the remotely controlled stop switch K01 and the local stop switch K02 are in the normally closed state and are respectively controlled by a remote control unit and a local control unit; the start switch combination includes a remotely controlled start switch K03 and a local start switch K04 connected in parallel. Both the remotely controlled start switch K03 and the local start switch K04 are in the normally open state and are respectively controlled by a remote control unit and a local control unit.

[0020] Among them, the remote control unit is generally a remote PLC. The local control unit is generally a local PLC, which can be installed in the control cabinet JXK. When automatic control is required, the manual-automatic changeover switch ZK is switched to connect to the automatic control circuit. The remotely controlled start switch K03 and the local start switch K04 can be respectively controlled by the remote control unit and the local control unit. After closing, the automatic control circuit can be connected. In addition, other components can be provided in the control circuit of the present application to increase the stability of the entire circuit. For example, the pump start auxiliary relay KA1 can be provided with two switches, and the other switch is connected in parallel with the start switch combination and can be closed during automatic control to play a self-holding role. Another example is that a soft start fault relay KA4 can be set on the control loop of the maintenance drainage pump. Its switch is in the normally closed state and is used to open the switch through the remote or local control unit when a fault occurs in the circuit, thereby disconnecting the entire loop. In addition, various indicator lights can be provided in the control circuit of the maintenance drainage pump to monitor the operating conditions of the power supply, the water filling valve, and the maintenance drainage pump.

[0021] It should be understood that all of the above embodiments are exemplary rather than restrictive. Under the concept of this application, those skilled in the art should make various modifications or deformations to the specific embodiments described above, and all of them should fall within the protection scope of this application.

Claims

1. A control circuit for repairing a drainage pump, characterized in that: It includes two first transmission lines and a second transmission line for transmitting alternating current, between which a manual-automatic switching switch, a control cabinet, a pump start auxiliary relay, a pump delay relay, a filling valve control relay, and a pump start control relay are arranged to form a maintenance drainage pump control circuit and a filling valve time control circuit; The maintenance drainage pump control circuit includes the manual-automatic switching switch, which is connected to the first transmission line and can be switched to a parallel manual control circuit and an automatic control circuit, both of which are connected to the coil of the pump start auxiliary relay and the static contact of the switch of the pump delay relay; the control cabinet is arranged on the automatic control circuit, and is used to control the on and off of the circuit by receiving a control signal; the switch of the pump delay relay is provided with a first moving contact and a second moving contact, and the static contact and the first moving contact are in a normally closed state, the first moving contact is connected to the coil of the water filling valve control relay, and the second moving contact is connected to the coil of the pump start control relay; the coil of the pump start auxiliary relay, the coil of the water filling valve control relay, and the coil of the pump start control relay are all connected to the second transmission line; The water filling valve time control loop includes a coil of the pump delay relay and a switch of the pump start auxiliary relay, which are connected in series between the first transmission line and the second transmission line; The switch of the water filling valve control relay is used as a switch for starting the water filling valve, and the switch of the pump start control relay is used as a switch for starting the maintenance drainage pump.

2. The control circuit for the maintenance drainage pump according to claim 1 is characterized in that: The control cabinet is provided with a stop switch combination and a start switch combination which are sequentially connected in series to the manual-automatic switching switch; the stop switch combination includes a remote stop switch and an on-site stop switch connected in series, both of which are in a normally closed state and are respectively controlled by a remote control unit and an on-site control unit; the start switch combination includes a remote start switch and an on-site start switch connected in parallel, both of which are in a normally open state and are respectively controlled by a remote control unit and an on-site control unit.

3. The control circuit for the maintenance drainage pump according to claim 1, characterized in that: A circuit breaker is provided on the first transmission line.

4. The control circuit for the maintenance drainage pump according to claim 1, characterized in that: An emergency stop button is provided on the first transmission line.

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