For the maintenance of frequency converter, there are many novices who are not familiar with the false load. They have saved many modules with the false load, because the novice maintenance personnel generally do not know how to do this. Now when the light is on, it means that the module will be broken again. False load is to use a resistor of several hundred ohm (light bulb can also be used) to connect it to the main circuit. If there is a fast fuse, remove it and install the resistance; if there is no fast fuse, it can be disconnected anywhere on the main circuit, and the resistor can be connected in series! This resistance plays a role of limiting current. When there is a short circuit in the module, the module will not be burned down. After starting up, the output of the inverter is normal, then the false load will be removed!

But the connection of false load should pay attention to several problems

1. It should be connected between the capacitor and the module, not between the rectifier and the capacitor, because the discharge of the capacitor is enough to burn the module.

2. When the power supply of switching power supply is through fast melting, the false load cannot be put on the fast melting device, otherwise the light bulb will be on after power transmission, and the switching power supply sometimes does not work!

3. The false load should also be connected behind the DC voltage detection point, so that when the inverter output is abnormal and the light is on, the inverter will not jump "low voltage", you can check which output is faulty!

Frequency converter has a common feature, that is, if the switching power supply of the inverter is not directly supplied from the filter capacitor of the main circuit, but from the input end, it is separately supplied from the main circuit. If the power supply is 380V, it is better to change the voltage to 220 V (rectifier) and then supply the switching power source. Although the inverter will be more complex, its failure rate will be greatly reduced! Because a lot of inverter failures and switching power supply relationship! When the frequency converter is running, the DC voltage of the main circuit is unstable. If the switching power supply is supplied from the filter capacitor of the main circuit, the switching power supply is easy to be broken!