Many motors now use soft starters as starting protection devices, so how to choose a soft starter?
1. Select the motor soft starter according to the standard load or heavy load. Choose different types of starters according to the nature of the load. If the load is a centrifugal pump (fire pump, spray pump, water pump, etc.), you need to use the pump control function to reduce the occurrence of water hammer in the system caused by the impact of liquid flow. If the load is a fan, you need to use the soft start function to reduce belt wear and mechanical shock.
2. Select the starter according to the nominal power, current and load nature of the motor. Generally, the capacity of the soft starter is slightly larger than the working current of the motor. For heavy-duty loads of the cement plant, the gear should be increased by one gear, such as: crusher, ball mill, elevator, long belt, mixer, fan, etc.And you need to consider the heat dissipation factors.
3. In other aspects, it is necessary to consider whether the protection function is complete.
Such as over-current protection, over-voltage protection, single ground protection, upper and lower opening phase protection, three-phase unbalance protection, phase reversal protection, etc. If there is no overload protection, it must be protected by another heating relay.