Anti-clogging self-switching control system for fire pump

Abstract

The utility model discloses an anti-blocking automatic switching control system for a fire pump, which comprises a main pump, a standby pump, a main control circuit, a standby control circuit and a PLC (Programmable Logic Controller) control module, a current detection module is arranged on a power supply circuit, and the current detection module is in communication connection with the PLC control module; the main control circuit and the standby control circuit are each provided with a cut-off relay and a starting relay, the cut-off relays and the starting relays are connected to the PLC control module, the PLC control module is provided with a locked-rotor current threshold value, and when the current value detected by the current transformer is larger than the locked-rotor current threshold value, the locked-rotor current threshold value is switched off. The PLC control module controls a cut-off relay in the main control circuit to be powered on so as to control the main pump to be disconnected from the power supply circuit, and meanwhile, the PLC control module controls a starting relay in the standby control circuit to be powered on so as to control the standby pump to be connected with the power supply circuit. According to the utility model, the motor can be effectively protected and prevented from being burnt due to stalling, and the main pump and the standby pump can be quickly and automatically switched.

Description

Technical Field

[0001] This utility model relates to the field of fire pump technology, and in particular to a fire pump anti-blocking automatic switching control system. Background Technology

[0002] In the field of fire protection, fire pumps are the core equipment in fire protection systems, responsible for providing a stable water pressure to ensure timely fire suppression and safe evacuation in the event of a fire.

[0003] Currently, existing fire pump controls only have short-circuit protection, typically cutting off the main control circuit when Isd = 10Ie. However, in practical applications, fire pumps often face stalling issues. Traditional fire pump control systems are significantly inadequate in handling stall situations (Istall = 3Ie~4Ie). Existing fire pump control systems lack effective real-time monitoring and judgment mechanisms, failing to detect stalling in a timely manner. When stalling occurs, the inability to take prompt action may lead to motor overheating, damaging both the motor and pump body. Furthermore, the inability to effectively switch to a backup pump in a timely manner results in insufficient water pressure and volume for the fire system at critical moments, posing a significant risk to fire fighting and severely impacting the normal operation and service life of the fire pumps. Therefore, it is necessary to improve existing technologies to overcome these shortcomings. Utility Model Content

[0004] The problem to be solved by this utility model is to provide a fire pump anti-locking automatic switching control system to overcome the defects of existing fire pump control systems that cannot cut off the main control circuit in time when dealing with lock-up situations, and also cannot switch to the standby pump in a timely and effective manner, resulting in motor burnout and serious impact on the normal operation of the fire pump.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a fire pump anti-lock-start automatic switching control system, comprising: a main pump, a standby pump, a main control circuit for controlling the start and stop of the main pump, a standby control circuit for controlling the start and stop of the standby pump, and a PLC control module. A current detection module is installed on the power supply circuit for supplying power to the main pump and the standby pump, and the current detection module is communicatively connected to the PLC control module. Both the main control circuit and the standby control circuit are provided with a cut-off relay and a start relay. The cut-off relay and the start relay are electrically connected to the PLC control module. The PLC control module is set with a lock-start current threshold. When the current value detected by the current detection module is greater than the lock-start current threshold, the PLC control module controls the cut-off relay in the main control circuit to be energized, thereby controlling the main pump to disconnect from the power supply circuit. At the same time, the PLC control module controls the start relay in the standby control circuit to be energized, thereby controlling the standby pump to be connected to the power supply circuit.

[0006] As a further improvement of this utility model, the cut-off relay and the start relay in the main control circuit are the seventh relay and the twenty-ninth relay, respectively, and the coils of the seventh relay and the twenty-ninth relay are electrically connected to the PLC control module.

[0007] As a further improvement of this utility model, the main control circuit includes a first main contactor, a second main contactor, and a third main contactor. The normally open contact of the twenty-ninth relay, the first normally closed contact of the seventh relay, the normally closed contact of the second main contactor, and the coil of the third main contactor are connected in series between the first phase line and the neutral line of the power supply circuit. The first normally open contact of the first main contactor and the first normally open contact of the third main contactor are connected in series and in parallel with the normally open contact of the twenty-ninth relay. One end of the second normally closed contact of the seventh relay is connected between the first normally open contact of the first main contactor and the first normally open contact of the third main contactor, and the other end is connected to the neutral line via the coil of the first main contactor. The normally closed contact of the third main contactor and the coil of the second main contactor are connected in series between one end of the second normally closed contact of the seventh relay and the neutral line.

[0008] As a further improvement of this utility model, the backup control circuit has the same circuit structure as the main control circuit.

[0009] As a further improvement of this utility model, the current detection module includes a current transformer and a comprehensive power transmitter. The comprehensive power transmitter is electrically connected to the current transformer and the PLC control module. The comprehensive power transmitter is used to transmit the current signal detected by the current transformer to the PLC control module.

[0010] As a further improvement of this utility model, each phase line of the power supply circuit is provided with a current transformer, and the PLC control module can respond according to the current signal detected by any one of the current transformers.

[0011] As a further improvement of this utility model, the PLC control module is also provided with a stall time threshold. When the current value detected by the current detection module is greater than the stall current threshold and exceeds the stall time threshold, the PLC control module controls the main control circuit to cut off and controls the backup control circuit to turn on.

[0012] As a further improvement of this utility model, both the main pump and the standby pump are connected to the power supply circuit via a star-delta start control wiring method.

[0013] The beneficial effects of this utility model are as follows: This utility model provides a fire pump anti-stalling automatic switching control system. By setting a current detection module, it can monitor the operating status of the main pump or the standby pump in real time and accurately. Once a stall phenomenon is detected, the PLC control module can respond immediately and cut off the corresponding main control circuit / standby control circuit, which can effectively protect the motor from stalling and burnout, and extend the service life of the fire pump. At the same time, the system can realize rapid automatic switching between the main pump and the standby pump, ensuring that the fire protection system restores normal water supply in the shortest possible time, which greatly improves the reliability and emergency response capability of the fire protection system. Attached Figure Description

[0014] Figure 1 This is a circuit diagram showing the connection between the main pump and the standby pump and the power supply circuit in the fire pump anti-blockage automatic switching control system of this utility model.

[0015] Figure 2 This is a circuit diagram of the main control circuit and the backup control circuit in the fire pump anti-blocking automatic switching control system of this utility model;

[0016] Figure 3 This is a circuit diagram of the PLC control module in the fire pump anti-blockage automatic switching control system of this utility model;

[0017] Figure 4 This is a circuit diagram of the current detection module in the fire pump anti-blockage automatic switching control system of this utility model.

[0018] Referring to the accompanying drawings, the following explanations are provided:

[0019] M1, Main pump; M2, Standby pump; 1KM1, First main contactor; 1KM2, Second main contactor; 1KM3, Third main contactor; 2KM1, First standby contactor; 2KM2, Second standby contactor; 2KM3, Third standby contactor; KA7, Seventh relay; KA8, Eighth relay; KA29, Twenty-ninth relay; KA30, Thirtieth relay; TA, Current transformer; L1, First phase line; N, Neutral line. Detailed Implementation

[0020] The preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0021] See Figures 1 to 4 This utility model provides a fire pump anti-blockage switching control system, including: a main pump M1, a standby pump M2, a main control circuit for controlling the start and stop of the main pump M1, a standby control circuit for controlling the start and stop of the standby pump M2, a PLC control module, and a power supply circuit.

[0022] The power supply circuit for supplying power to the main pump M1 and the standby pump M2 is equipped with a current detection module, which is communicatively connected to the PLC control module. Both the main control circuit and the standby control circuit are equipped with cut-off relays and start relays, both of which are electrically connected to the PLC control module.

[0023] In this invention, the PLC control module is equipped with a stall current threshold.

[0024] When the main pump M1 is in working condition and the standby pump M2 is in standby condition, if the current value detected by the current detection module is greater than the stall current threshold, the PLC control module can control the cut-off relay in the main control circuit to be energized, cut off the main control circuit, and thus control the main pump M1 to be disconnected from the power circuit. At the same time, the PLC control module can control the start relay in the standby control circuit to be energized, and thus control the standby pump M2 to be connected to the power circuit.

[0025] Similarly, when the standby pump M2 is in the working state and the main pump M1 is in the standby state, if the current value detected by the current detection module is greater than the stall current threshold, the PLC control module can also control the cut-off relay in the standby control circuit to be energized, cut off the standby control circuit, and thus control the standby pump M2 to be disconnected from the power circuit. At the same time, the PLC control module can also control the start relay in the main control circuit to be energized, and thus control the main pump M1 to be connected to the power circuit.

[0026] As can be seen, the fire pump anti-stalling automatic switching control system of this utility model, by setting a current detection module, can monitor the operating status of the main pump M1 or the standby pump M2 in real time and accurately. Once a stall phenomenon is detected, the PLC control module can respond immediately and cut off the corresponding main control circuit / standby control circuit, which can effectively protect the motor from stalling and burnout, and extend the service life of the fire pump. At the same time, the system can quickly and automatically switch to the standby pump M2 to ensure that the fire protection system restores normal water supply in the shortest possible time, which greatly improves the reliability and emergency response capability of the fire protection system.

[0027] See Figure 1 and Figure 4 The current detection module includes a current transformer (TA) and a power transmitter. The current transformer (TA) is installed on the power supply circuit, and the power transmitter is electrically connected to the current transformer (TA) and the PLC control module. The power transmitter is used to transmit the current signal detected by the current transformer (TA) to the PLC control module.

[0028] It is worth mentioning that current transformers (CTs) are installed on all three phase lines of the power supply circuit, and the PLC control module can respond based on the current signal detected by any one of the CTs. This invention ensures complete current information in the power supply circuit by simultaneously detecting the three-phase current, avoiding the omission of any abnormal situation in any phase, achieving comprehensive monitoring, improving system reliability, and ensuring that the fire pump can operate normally in the event of a fire.

[0029] In addition, the PLC control module is also set with a stall time threshold. In this embodiment, the stall time threshold is specifically set to 5 seconds. When the current value detected by the current detection module is greater than the stall current threshold and exceeds 5 seconds, the PLC control module will control the main control circuit to cut off and control the backup control circuit to turn on, thereby avoiding false detection caused by the large current when the main pump M1 or the backup pump M2 starts.

[0030] like Figure 1 and Figure 2 As shown, in this utility model, both the main pump M1 and the standby pump M2 are connected to the power circuit via a star-delta start control wiring method.

[0031] See Figure 2 and Figure 3 The cut-off relay and start relay in the main control circuit are the seventh relay KA7 and the twenty-ninth relay KA29, respectively. The coils of the seventh relay KA7 and the twenty-ninth relay KA29 are electrically connected to the PLC control module.

[0032] like Figure 2As shown, the main control circuit includes a first main contactor 1KM1, a second main contactor 1KM2, and a third main contactor 1KM3. The normally open contact of the twenty-ninth relay KA29, the first normally closed contact of the seventh relay KA7, the normally closed contact of the second main contactor 1KM2, and the coil of the third main contactor 1KM3 are connected in series between the first phase line L1 and the neutral line N of the power supply circuit. The first normally open contact of the first main contactor 1KM1 and the first normally open contact of the third main contactor 1KM3 are connected in series and then in parallel with the normally open contact of the twenty-ninth relay KA29. One end of the second normally closed contact of the seventh relay KA7 is connected between the first normally open contact of the first main contactor 1KM1 and the first normally open contact of the third main contactor 1KM3, and the other end is connected to the neutral line N via the coil of the first main contactor 1KM1. The normally closed contact of the third main contactor 1KM3 and the coil of the second main contactor 1KM2 are connected in series between one end of the second normally closed contact of the seventh relay KA7 and the neutral line N.

[0033] Among them, the second normally open contact of the first main contactor 1KM1, the normally open contact of the second main contactor 1KM2, and the second normally open contact of the third main contactor 1KM3 are... Figure 1 The wiring shown is connected between the main pump M1 and the power supply circuit. This is the existing conventional wiring method, used to realize the star-delta start control of the main pump M1.

[0034] See Figure 2 and Figure 3 The backup control circuit has the same circuit structure as the main control circuit. Specifically, in this utility model, the cut-off relay and the start relay in the backup control circuit are the eighth relay KA8 and the thirtieth relay KA30, respectively. The coils of the eighth relay KA8 and the thirtieth relay KA30 are both electrically connected to the PLC control module.

[0035] like Figure 2As shown, the backup control circuit includes a first backup contactor 2KM1, a second backup contactor 2KM2, and a third backup contactor 2KM3. The normally open contact of the thirtieth relay KA30, the first normally closed contact of the eighth relay KA8, the normally closed contact of the second backup contactor 2KM2, and the coil of the third backup contactor 2KM3 are connected in series between the first phase line L1 and the neutral line N of the power supply circuit. The first normally open contact of the first backup contactor 2KM1 and the first normally open contact of the third backup contactor 2KM3 are connected in series and then in parallel with the normally open contact of the thirtieth relay KA30. One end of the second normally closed contact of the eighth relay KA8 is connected between the first normally open contact of the first backup contactor 2KM1 and the first normally open contact of the third backup contactor 2KM3, and the other end is connected to the neutral line N via the coil of the first backup contactor 2KM1. The normally closed contact of the third backup contactor 2KM3 and the coil of the second backup contactor 2KM2 are connected in series between one end of the second normally closed contact of the eighth relay KA8 and the neutral line N.

[0036] Among them, the second normally open contact of the first backup contactor 2KM1, the normally open contact of the second backup contactor 2KM2, and the second normally open contact of the third backup contactor 2KM3 are... Figure 1 The wiring shown is connected between the standby pump M2 and the power supply circuit. This is the existing conventional wiring method, used to realize the star-delta start control of the standby pump M2.

[0037] In addition, such as Figure 2 As shown, the main control circuit and the backup control circuit are also connected to time relays and other relays, which are conventional technical means well known to those skilled in the art, so they will not be described in detail here.

[0038] Taking the main pump M1 in working state and the standby pump M2 in standby state as an example: The integrated power transmitter reads the current through the current transformer TA and transmits the current data to the PLC control module. When the detected current value is greater than the set stall current threshold and exceeds the stall time threshold, the PLC control module controls the coil of the seventh relay KA7 to be energized. The first normally closed contact and the second normally closed contact of the seventh relay KA7 are both opened. The coils of the first main contactor 1KM1 and the third main contactor 1KM3 are both de-energized. The first normally open contact of the first main contactor 1KM1 and the first normally open contact of the third main contactor 1KM3 are both opened. The secondary circuit self-locking is broken. The coil of the second main contactor 1KM2 is de-energized, thereby cutting off the main control circuit of the main pump M1. Meanwhile, the PLC control module energizes the coil of the 30th relay KA30 in the backup control circuit, closing the normally open contact of the 30th relay KA30, energizing the coil of the third backup contactor 2KM3, and closing the first normally open contact of the third backup contactor 2KM3. This energizes the coil of the first backup contactor 2KM1, which in turn closes the first normally open contact of the first backup contactor 2KM1, energizing the coil of the second backup contactor 2KM2. During this process, in conjunction with the time relay in the backup control circuit, a delay control is performed when the backup pump M2 starts, ensuring that the backup pump M2 switches to the delta connection for full-voltage operation after starting in the star connection for a period of time.

[0039] Many specific details have been set forth in the above description to provide a full understanding of this utility model. However, the above description is only a preferred embodiment of this utility model, and this utility model can be implemented in many other ways different from those described herein. Therefore, this utility model is not limited to the specific embodiments disclosed above. Furthermore, any person skilled in the art can make many possible variations and modifications to the technical solution of this utility model using the methods and techniques disclosed above, or modify it into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model, without departing from the content of the technical solution of this utility model, shall still fall within the protection scope of the technical solution of this utility model.

Claims

1. A fire pump anti-blockage switching control system, comprising a main pump (M1), a standby pump (M2), a main control circuit for controlling the start and stop of the main pump (M1), a backup control circuit for controlling the start and stop of the standby pump (M2), and a PLC control module, characterized in that: A current detection module is installed on the power supply circuit for supplying power to the main pump (M1) and the standby pump (M2). The current detection module is communicatively connected to the PLC control module. Both the main control circuit and the standby control circuit are equipped with a cut-off relay and a start relay. The cut-off relay and the start relay are electrically connected to the PLC control module. The PLC control module is equipped with a stall current threshold. When the current value detected by the current detection module is greater than the stall current threshold, the PLC control module controls the cut-off relay in the main control circuit to be energized, thereby controlling the main pump (M1) to be disconnected from the power supply circuit. At the same time, the PLC control module controls the start relay in the standby control circuit to be energized, thereby controlling the standby pump (M2) to be connected to the power supply circuit.

2. The fire pump anti-blocking switching control system according to claim 1, characterized in that: The cut-off relay and start relay in the main control circuit are the seventh relay (KA7) and the twenty-ninth relay (KA29), respectively. The coils of the seventh relay (KA7) and the twenty-ninth relay (KA29) are both electrically connected to the PLC control module.

3. The fire pump anti-blockage switching control system according to claim 2, characterized in that: The main control circuit includes a first main contactor (1KM1), a second main contactor (1KM2), and a third main contactor (1KM3). The normally open contact of the twenty-ninth relay (KA29), the first normally closed contact of the seventh relay (KA7), the normally closed contact of the second main contactor (1KM2), and the coil of the third main contactor (1KM3) are connected in series between the first phase line (L1) and the neutral line (N) of the power supply circuit. The first normally open contact of the first main contactor (1KM1) and the first normally open contact of the third main contactor (1KM3) are connected in series and parallel. The normally open contact of the 29th relay (KA29) is connected to the neutral line (N); one end of the second normally closed contact of the 7th relay (KA7) is connected between the first normally open contact of the first main contactor (1KM1) and the first normally open contact of the third main contactor (1KM3), and the other end is connected to the neutral line (N) via the coil of the first main contactor (1KM1); the normally closed contact of the third main contactor (1KM3) and the coil of the second main contactor (1KM2) are connected in series between one end of the second normally closed contact of the 7th relay (KA7) and the neutral line (N).

4. The fire pump anti-blocking switching control system according to claim 3, characterized in that: The backup control circuit has the same circuit structure as the main control circuit.

5. The fire pump anti-blocking switching control system according to claim 1, characterized in that: The current detection module includes a current transformer (TA) and a comprehensive power transmitter. The comprehensive power transmitter is electrically connected to the current transformer (TA) and the PLC control module. The comprehensive power transmitter is used to transmit the current signal detected by the current transformer (TA) to the PLC control module.

6. The fire pump anti-blocking automatic switching control system according to claim 5, characterized in that: Each phase line of the power supply circuit is equipped with a current transformer (TA), and the PLC control module can respond based on the current signal detected by any one of the current transformers (TA).

7. The fire pump anti-blocking switching control system according to claim 1, characterized in that: The PLC control module is also set with a stall time threshold. When the current value detected by the current detection module is greater than the stall current threshold and exceeds the stall time threshold, the PLC control module controls the main control circuit to cut off and controls the backup control circuit to turn on.

8. The fire pump anti-blocking switching control system according to claim 1, characterized in that: Both the main pump (M1) and the standby pump (M2) are connected to the power supply circuit via a star-delta start control wiring method.

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