User Manual of EM760 High-Performance Inverter 3.2.4.2 Installation of leakage circuit breaker Since the inverter outputs high-frequency PWM signals, a high-frequency leakage current will be generated. Please use the dedicated leakage circuit breaker with the current sensitivity above 30 mA. If an ordinary leakage circuit breaker is used, use a leakage circuit breaker with the current sensitivity above 200 mA and action time of more than 0.1 s. 3.2.4.3 Installation of electromagnetic contactor Connect the electromagnetic contactor that matches the power of the inverter, as shown in Fig. 3-9 Connection of Input Circuit Breaker.
● Do not control the operation and stop of the inverter via the electromagnetic contactor on the incoming line side. Frequent use of this method is an important cause of damage to the inverter. The frequency of operation and stop of the electromagnetic contactor on the incoming line side must not exceed once every 30 min. ● After the power supply is restored, the inverter will not run automatically. 3.2.4.4 Connection with terminal block The phase sequence ofthe input power supply is unrelated to that (R, S, T) ofthe terminal block, so that the terminals of the input power supply can be connected arbitrarily.
3.2.4.5 Installation of AC reactor When a large-capacity (above 600KVA) power transformer is connected, or the input power supply is connected to a capacitive load, a high inrush current will be generated, which will cause damage to the rectifier part of the inverter. In this case, please connect a three-phase AC reactor (optional) to the input side of the inverter. This will not only suppress the peak current and voltage, but also improve the power factor of the system.
3.2.4.6 Installation of surge suppressor When an inductive load (electromagnetic contactor, solenoid valve, solenoid coil, electromagnetic circuit breaker, etc.) is connected near the inverter, please install a surge suppressor. 3.2.4.7 Installation of noise filter on power supply side The noise filter is used to suppress the noise that invades the inverter from the power cable, and the impact of inverter noise on the power grid. ● Use a dedicated noise filter for the inverter. Ordinary noise filters do not have good effects, so they are not used usually. ● The correct and incorrect installations of the noise filter are shown below. 47