Soft Starter Troubleshooting
Short-phase failure occurs in the debugging and the trouble light of soft starter lights on while motor doesn't act. Possible causes for the failure may be:
When the starting mode is charged, the operation sequence is wrong (the correct operation sequence should be to send the main power first and then the control power). The power supply shorts phase and soft starter protection acts (check the power supply). Output of the soft starter is not connected with load (the soft starter can work normally only after the output is connected with loads).
If the soft starter has started but the bypass contactor fails to attract. Possible causes for the failure may be:
During the starting process, the protection device makes malfunction due to the smaller setting (resetting the protection device). Parameter setting of soft starter is unreasonable when setting. (It's mainly aimed at soft starters below 55KW, resetting the parameters of the soft starter) Bad contact of the control circuit (check the contact)
Air switch trips occasionally during the starting process. Causes may be:
Delay setting of the air switch is too small or the air switch doesn't match with the motor (enlarge the parameters of air switch or choose a proper air switch). Starting voltage of the soft starter is set highly or starting time is too long (reduce the starting voltage according to the load conditions or shorten the starting time). During the starting process, large fluctuation of the grid voltage would cause the soft starter to give erroneous instructions and thus occurring the advance bypass (Users are advised not to start high power motors at the same time). Star at full load (reduce loads when starting).
The display screen has no display or displays messy codes when the user uses the soft starter, the soft starter doesn't work. Possible causes may be:
Internal connection wire of the soft starter loosens due to vibration of external parts when the soft starter is working (open the external cover of the soft starter and connect tightly the wires of display screen); Control board of the soft starter breaks (contact the manufacturer to replace a new one).
Soft starter gives failure warning when starting, it can't work and the motor doesn't run. Possible causes may be:
Phase absence of motor (check motor and peripheral circuits). Silicon control of main component in the soft starter shorts (check whether the motor and grid voltage are abnormal. Contact the manufacturer to replace a new silicon control) Short circuit caused by breakdown of filter board (replace the filter board).
Overtime starting when the soft starter starts a load, the soft starter stops and the motor pulls up freely. Causes may be:
Improper parameters setting (resetting parameters, increase the starting voltage and time slightly ). Full-load starting (reduce the load when starting)
Current is unstable when starting, the current is excessively large. Possible causes may be:
Ammeter can't indicate accurately or doesn't match with the inductor (replace with a new ammeter). The grid voltage is unstable and the fluctuation is relatively large, leading to malfunctions of the soft starter (contact the manufacturer to replace a control board). Parameters of the soft starter are not properly set (reset parameters ).
Soft starter starts repeatedly. Possible causes may be:
Peripheral protective elements act during starting, the contactor can't attract, as a result, the soft starter starts repeatedly (check the peripheral elements and circuits).
Overheating trouble light flashes at starting and the soft starter stops work. Causes may be:
Frequent starting leads to excessively high temperature, overheating protection of the soft starter thereof operates (starting frequency of the soft starter shall be controlled within 6 times per hour, particularly in heavy load). Protective elements act at starting, which makes the contactor unable to by pass, the soft starter works for long time and thus causing the protection to act (check peripheral circuit). Heavy load and long starting time lead to overheating protection (reduce load as far as possible when starting). Parameters of soft starter are improperly set. Long starting time and low starting voltage (increase the starting voltage). Radiator fan of the soft starter can't work normally (replace a fan).