Why does the soft starter of permanent magnet variable frequency air compressor often fail? What is the reason?


Permanent magnet variable frequency air compressor is a popular model in recent years, its power consumption is much less than the same model, but some users often worry because of its soft starter failure, so how to deal with these failures?


Soft starter is a kind of motor control equipment which integrates soft start, soft stop, light load energy saving and multi-function protection. It can start the motor smoothly without impact in the whole starting process, and automatically adjust various parameters in the starting process according to the characteristics of motor load.

Permanent magnet variable frequency air compressor

1、 Problems during debugging:

Generally, the air compressor starts to report phase failure, and the fault light of the soft starter is on, and the motor has no response.

reason:

1. It is caused by the wrong operation sequence when the live mode is adopted;

2. Check the power supply, check whether the power supply is lack of phase, soft starter protection action, etc;

3. Check whether the output terminal of soft starter is not connected with load.

2)、 Problems in use:

After the air compressor is started, the bypass contactor does not close.

reason:

1. It may be the wrong action of the protection device due to the setting is too small during the starting process.

2. It may be caused by unreasonable parameter setting in soft starter.

3. Poor contact of control circuit (check control circuit).

3、 Problems during startup:


The air compressor has the trouble of tripping the air switch


reason:

1. It may be that the setting value of the air switch delay is too small, or that the air switch selection is not matched with the motor. Try to enlarge the parameters of the air switch appropriately, or re select the model of the air switch.

2. It may be caused by the improper setting of starting voltage parameters of soft starter. Too high or too long starting time will lead to the fault of air switch tripping. The starting voltage must be appropriately reduced or the starting time must be appropriately shortened according to the load condition, so as to better avoid the problem.

3. It may be that the voltage fluctuation is large, which causes the soft starter to issue wrong command, leading to bypass in advance.

4. It may be caused by full load startup.

4、 There is a problem with the display:

The soft starter doesn't work when the display screen doesn't show or the code is garbled.

reason:

1. Due to the vibration of external components, the internal wiring of the soft starter is loose. You need to open the cover of the soft starter, re plug the wiring of the display screen, and start it to see if there is any abnormality.

(2) Soft starter control board failure.

5、 Load startup timeout problem:

reason:

1. Unreasonable parameter setting

2. Start at full load

6、 Current instability during startup:

1. It may be caused by incorrect indication of ammeter or mismatch with transformer.

2. The instability of power grid voltage may cause the soft starter misoperation.

3. The parameter setting may be unreasonable.

7、 The soft starter starts repeatedly.

Check whether there is any problem with the peripheral components and circuits. It may be that the peripheral protection components act during the starting process of the soft starter, but the contactor can't pull in, resulting in the repeated starting of the soft starter.

8、 When starting, the overheat fault light is on, and the soft starter stops working

1. Frequent start-up may lead to overheating of temperature rise, which may lead to overheating protection behavior of soft starter.

2. Check the peripheral circuit. It may be that the contactor can not be bypassed due to the action of the protection element during the start-up process. The soft starter works for a long time, which causes the protection action and the overheat light is on.

3. Overload and long starting time lead to overheat protection.

4. The parameter setting of soft starter is not reasonable. If the time is long, the starting voltage will be too low.

5. The heat dissipation of the soft starter is poor, check whether the cooling fan is faulty, or the current working environment temperature is too high.