Soft starter is a novel motor control device that integrates motor soft start, soft stop, light load energy saving and multiple protection functions. It is called Soft Starter abroad. The domestic soft starter is the most famous Heping hps2 series soft starter. Its main composition is a three-phase parallel thyristor and its electronic control circuit connected in series between the power supply and the controlled motor.

The soft starter we use needs to be powered on. Generally, we need to check before power on before use. Let's take a look with the editors below to see which ones to check:

First, check the wiring

1. Check whether the wiring is correctly connected in accordance with the requirements of the product instruction manual, especially pay attention not to connect the output terminals (U, V, W) to the three-phase power supply.

2. Check whether the installation is normal and whether the grounding is correct and reliable. Especially for the control circuit wiring (such as the given signal line and feedback signal line on the input side, the frequency signal line and current signal line on the output side, the switch signal control line, etc.), it is necessary to keep away from the main circuit (more than 100mm) and shield Anti-interference measures. The shield of the cable should be connected to the common end (COM) of the control circuit near the inverter. Do not connect to the ground (PE) of the inverter. The other end of the shield should be suspended.

3. Check whether the brake unit wiring is correct. When connecting an external braking resistor (some inverters have a built-in braking resistor, when the capacity is insufficient, an external braking resistor is required), first remove the wiring of the built-in braking resistor from the P (+) and DBd terminals, and The wire end is insulated, and then the external braking resistor is connected to P (+) and DB. It is required that the wiring length is less than 5M, and twisted pairs are used.

4. Check whether the DC reactor wiring is correct. Note: Short-circuit conductors are connected to the connection terminals P1 and P (+) when leaving the factory. When using a DC reactor, this short-circuit conductor should be removed; if a DC reactor is not used, the short-circuit conductor can be connected at both ends of the reactor.

2. Check AC power. For three-phase inverters, the three-phase AC power supply voltage should be within the allowable range (such as 340-440v). Overvoltage and undervoltage are strictly prohibited.

Third, check the motor

1. Use a 500V-1000V megohmmeter to measure the insulation resistance of the motor winding to the shell, which should not be less than 5 megohms. If the insulation resistance is less than 2 megohms or the winding has been in contact with the shell, it is strictly prohibited to use the inverter. Otherwise, the inverter will be damaged.

2. Measure the DC resistance between the three windings of the motor, which should be balanced in three phases, and the resistance between the windings of each phase is ohms. If the resistance is too small or zero, it means that there is a short circuit in the motor winding, and it is strictly forbidden to use it.

In general, when we check the power of the soft starter, we also need to pay attention to the above points to reduce failures due to power problems during use.