The newly installed water pump motor will not start properly
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Hello everyone. There is a problem with motors that are started using the direct star-delta method: After replacing old pumps with new ones, there are two such motors. When started in star-delta mode, they start after a delay of about ten seconds; the motor runs in forward direction, the pressure is normal, and the current levels are also normal. However, when the connection changes to another mode, the motor stops running, and the overload protector does not trip – it is necessary to manually stop the motor to disconnect the circuit. May the wiring be incorrect even when the motor is running in forward direction? Since a single startup is normal and all operational parameters are also within the normal range, can we rule out problems with the wiring on the motor side? The motor equipped with soft start fails to start properly. Three new pumps were installed, connected in a delta configuration, but the soft start device shows no response and the motor does not rotate. I’m not familiar with circuits. In the past, I encountered situations where incorrect wiring of the motor caused it to rotate in the opposite direction. Based on that, if the order of the wires is reversed, the motor should at least rotate in the opposite direction, right? Now the soft start cannot be initiated at all. Tomorrow, the wiring will be checked again; if there are no issues with the wiring, the new pump’s wiring will be connected to the wiring of the old pump that is working properly, in order to conduct troubleshooting tests. Apart from that, what other possible causes and troubleshooting methods are there? Thank you?
As a supplementary note, soft starting was previously used for 55 kilowatts; now the pump has a capacity of 37 kilowatts. Is it necessary to adjust the parameters of the soft starter? Could the inability to start be due to adjusted parameters?
To replace the pump, first rotate it to check if it turns smoothly. Secondly, assuming there are no issues with the secondary circuit, when using star-delta starting, you should check whether the connection plates in the motor’s wiring box have been removed; if so, it is still a problem related to the phase sequence of the wiring. The normal order should be U1, V1, W1, W2, U2, V2. For soft start, check whether the connection pieces are properly attached, and then verify the setting for the multiple of the starting current for soft start; refer to the manual for details.
Hello, what company are we in?