CN219039300U

CN219039300U - Electrode fault judging circuit of liquid level relay of drainage system

Info

Publication number: CN219039300U
Application number: CN202320029806.8U
Authority: CN
Inventors: 严宝强; 王彦彪; 王升; 闫冬生
Original assignee: Inner Mongolia Yitai Guanglian Coalification Co ltd; Inner Mongolia Zhongyu Taide Coal Co ltd; Ordos Zhongyu Taide Coal Co ltd
Current assignee: Inner Mongolia Yitai Guanglian Coalification Co ltd; Inner Mongolia Zhongyu Taide Coal Co ltd; Ordos Zhongyu Taide Coal Co ltd
Priority date: 2023-01-04
Filing date: 2023-01-04
Publication date: 2023-05-16
Anticipated expiration: 2033-01-04

Abstract

The utility model discloses a drainage system liquid level relay electrode fault judging circuit, wherein in a control loop, a normally closed contact of an intermediate relay KA, a normally closed contact of a delay relay KT and coils of an alternating current contactor form a closed loop, and the coils of the delay relay KT are connected in parallel at two ends of the coils of the alternating current contactor KM; the delay closed normally open contact of the delay relay KT and the alarm form a closed loop, and the coil of the intermediate relay KA is connected in parallel with the two ends of the alarm; the normally open contacts of the intermediate relay KA are connected in parallel with two ends of the normally open contacts of the delay relay KT; the advantages are that: the operation condition of the liquid level relay electrode is monitored by using the time relay, if the liquid level relay does not act after the time delay is finished, the liquid level relay is indicated to be damaged, and a patrol personnel is timely reminded to carry out patrol by an alarm system; the delay disconnection contact timely disconnects the drainage pump, so that idling of the drainage pump is avoided.

Description

Electrode fault judging circuit of liquid level relay of drainage system

Technical field:

the utility model relates to the field of monitoring of liquid level relays, in particular to a drainage system liquid level relay electrode fault judging circuit.

The background technology is as follows:

the liquid level relay is a relay for realizing control according to the liquid level, can realize circuit on-off according to the liquid level condition, and plays an important role in the automation of a drainage system. For example, in a water drainage control circuit of a heating water return tank of a coal washery, a water pump of a main loop is controlled by a liquid level relay with an electrode measurement function to realize a water return function; the control logic is as follows: in the control loop, a normally closed contact of a liquid level relay is connected in series with a coil of an alternating current contactor KM; meanwhile, in the main loop, a normally open contact of the alternating current contactor KM is connected in series with a motor of the water pump. When the water quantity in the water tank is at the high liquid level set by the liquid level relay, the normally closed contact of the liquid level relay is in a closed state, the coil and the normally open contact of the alternating current contactor KM are powered on, the water return pump is controlled to start, the water in the water return tank is returned to the boiler room for continuous heating, when the liquid level in the water return tank reaches the low liquid level set by the liquid level relay, the normally closed contact of the liquid level relay is disconnected, the coil and the normally open contact of the alternating current contactor KM are powered off, and the water pump is controlled to automatically stop running.

In this in-process liquid level relay needs to soak in water for a long time work, because frequent use and lack the maintenance for a long time, the electrode of liquid level relay can lead to contacting failure because of its surface rust, perhaps the surface is covered by the incrustation scale and can not be electrically conductive for liquid level relay is damaged, can't in time break its normally closed contact according to the liquid level, make the drain pump still idle running under the condition that does not have water at the water tank, the long-time operation leads to the fact the burnout easily, consequently, need effectual electrode trouble judgement circuit, realize the monitoring to liquid level relay running state, and can in time break off the drain pump under the liquid level relay damage condition, avoid the motor risk of burnout.

The utility model comprises the following steps:

the utility model aims to provide a liquid level relay motor fault judging circuit which can monitor the running condition of a liquid level relay, timely disconnect a drainage pump under the condition that the liquid level relay is damaged and timely alarm.

The utility model is implemented by the following technical scheme: a liquid level relay electrode fault judging circuit of a drainage system comprises a delay relay KT, an intermediate relay KA and an alarm; the coil of the delay relay KT is connected in parallel with two ends of the coil of the alternating current contactor KM connected in series with the normally closed contact of the liquid level relay; the normally closed contact of the intermediate relay KA, the normally closed contact of the delay relay KT, the normally closed contact of the liquid level relay and the coil of the delay relay KT form a closed loop; the delay closed normally open contact of the delay relay KT and the alarm form a closed loop, and the coils of the intermediate relay KA are connected in parallel at two ends of the alarm; and normally open contacts of the intermediate relay KA are connected in parallel with two ends of a normally open contact of the delay relay KT.

Preferably, the alarm is an audible and visual alarm or an indicator light.

Preferably, the alternating current contactor further comprises a main loop, wherein the main loop comprises a drainage pump and a breaker QF, and a normally open contact of the alternating current contactor KM is connected between the drainage pump and the breaker QF.

Preferably, the delay time of the delay relay KT is set to be the running time of the drainage pump for draining the water in the drainage system.

The utility model has the advantages that: the control circuit has simple structure and is easy to realize; the method comprises the steps that monitoring on the operation condition of an electrode of a liquid level relay is achieved through a time relay, the time delay time of the time delay relay is set to be the operation time of a drainage pump for draining water in a drainage system, if a normally closed contact of the liquid level relay does not act after time delay, the liquid level relay is indicated to be damaged, and inspection personnel are timely reminded to conduct inspection through an alarm system; when the liquid level relay fails, the delay disconnection contact of the delay relay timely disconnects the drainage pump to avoid idling of the drainage pump, and meanwhile, the intermediate relay disconnects the control loop again to avoid the time relay from entering the next timing cycle.

Description of the drawings:

in order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a circuit diagram of a control loop of the present utility model.

Fig. 2 is a main loop circuit diagram of the present utility model.

Fig. 3 is a schematic diagram of the use of the level relay of the present utility model.

The device comprises a drainage pump 1, an alarm 2, a liquid level relay 3, a normally closed contact 3-1 of the liquid level relay and a water tank 4.

The specific embodiment is as follows:

the following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Example 1:

fig. 1-2 show a failure judging circuit for the electrode of the liquid level relay of the drainage system, wherein fig. 1 is a control loop, fig. 2 is a main loop, and the control loop is used for detecting the electrode operation condition of the liquid level relay and automatically controlling the drainage pump 1 of the main loop.

As shown in fig. 1, the control loop includes a delay relay KT, an intermediate relay KA, and an alarm 2. The coil of the delay relay KT is connected in parallel with the two ends of the coil of the alternating current contactor KM, and a closed loop is formed by the normally closed contact of the intermediate relay KA, the normally closed contact of the delay relay KT, the normally closed contact 3-1 of the liquid level relay and the coil of the delay relay KT; the delay closed normally open contact of the delay relay KT and the alarm 2 form a closed loop, and the coils of the intermediate relay KA are connected in parallel with the two ends of the alarm 2; the normally open contacts of the intermediate relay KA are connected in parallel with two ends of the normally open contacts of the delay relay KT in a delay closing manner.

The alarm 2 may be an audible and visual alarm or an indicator light, and in this embodiment, the alarm 2 is an indicator light.

As shown in fig. 2, the main circuit includes a drain pump 1, a breaker QF, and a thermal relay FR, and a normally open contact of an ac contactor KM is connected between the thermal relay FR and the breaker QF.

Description of use: the delay time of the delay relay KT is first set as the running time required for the drain pump 1 to drain the water in the drain system.

As shown in fig. 3, the liquid level relay 3 monitors the liquid level of the water tank 4, and when the electrode of the liquid level relay 3 fails, the drainage system works normally, and the specific process is as follows: when the liquid level in the water tank 4 is at a preset high liquid level, the normally-closed contact 3-1 of the liquid level relay 3 is closed, the coil of the alternating-current contactor KM is powered on by switching off the normally-closed contact through the normally-closed contact of the intermediate relay KA and the time delay of the time relay KT, correspondingly, the normally-open contact of the alternating-current contactor KM in the main loop is closed, and the drainage pump 1 starts to work; when the drainage pump 1 drains water so that the liquid level in the water tank 4 is at a preset low liquid level, the normally closed contact of the liquid level relay 3 is disconnected, the coil of the alternating current contactor KM is powered off, the normally open contact is disconnected, and the drainage pump 1 of the main loop is controlled to stop running.

When the electrode of the liquid level relay 3 fails, the liquid level relay 3 cannot disconnect the normally closed contact 3-1 according to the liquid level in the water tank 4, so that the drain pump 1 is in an idling state after the water in the water tank 4 is emptied, and the drain pump 1 is controlled through the intermediate relay KA and the time relay KT.

The specific working process is as follows: the normally closed contact 3-1 of the liquid level relay 3 is always in a closed state, when the running time of the drainage pump 1 exceeds the set time of the delay relay KT, the delay cut-off normally closed contact of the delay relay KT is cut off, the coil of the alternating current contactor KM is powered off, the drainage pump 1 stops running, and long-term idling of the drainage pump 1 is avoided to burn out a motor. Meanwhile, a normally open contact is closed after the delay closing of the delay relay KT, the coil of the intermediate relay KA is electrified to generate self-locking, and when the coil of the intermediate relay KA is electrified, an indicator lamp for indicating electrode faults is always on to remind a worker to check the liquid level relay 3 and the electrodes thereof; the normally closed contact of the intermediate relay KA cuts off the coil of the alternating current contactor KM again, so that the delay relay KT is prevented from repeatedly entering the next round of timing.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.

Claims

1. The liquid level relay electrode fault judging circuit of the drainage system is characterized by comprising a delay relay KT, an intermediate relay KA and an alarm;

the coil of the delay relay KT is connected in parallel with the two ends of the coil of the alternating current contactor KM which is connected in series with the normally closed contact of the liquid level relay;

the normally closed contact of the intermediate relay KA, the normally closed contact of the delay relay KT, the normally closed contact of the liquid level relay and the coil of the delay relay KT form a closed loop;

the delay closed normally open contact of the delay relay KT and the alarm form a closed loop, and the coils of the intermediate relay KA are connected in parallel at two ends of the alarm;

and normally open contacts of the intermediate relay KA are connected in parallel with two ends of a normally open contact of the delay relay KT.

2. The liquid level relay electrode fault judging circuit of a drainage system according to claim 1, wherein the alarm is an audible and visual alarm or an indicator lamp.

3. The drain system level relay electrode fault determination circuit according to any one of claims 1 or 2, further comprising a main circuit including a drain pump and a circuit breaker, wherein a normally open contact of the ac contactor is connected between the drain pump and the circuit breaker.

4. A drain system level relay electrode fault determination circuit according to claim 3, wherein the delay time of the delay relay KT is set to be the running time of the drain pump to drain the water in the drain system.