How do we find the micro inverter motor rotor broken bar?

Check the micro inverter motor rotor broken bar has the following several general methods.

(1) the method of observation

Dongguan dc factory take out the micro motor rotor, carefully observe the rotor core surface, especially of rotor end ring and conducting bar junction, if found to have green color blue overheating phenomenon, that it is the place where the article is broken.

(2) substitution method

If conditions allow, also can be the same specifications of the micro change, frequency conversion motor rotor test run, if the micro inverter motor load capacity, rotational speed, sound, such as normal, then substituted article break fault of rotor.

(3) the short circuit detection method

Dongguan dc factory will have on 220 v ac power and string ammeter notches, short circuit detector in core and along the cylindrical rotor core gradually move, if discover the ammeter reading suddenly become smaller, slot inside the article break fault being measured. Also can use iron to replace the current meter, if can absorb and emit "squeak" sound, that conducting bar not broken; Otherwise the conducting bar fracture.

(4) iron powder method

With a secondary side current rating for the single-phase transformer and a capacity of more than 10 a considerable single-phase voltage regulator and the ac current meter connected, the ends of the rotor ring transformer secondary side. Dongguan dc factory inspection first turn on the output voltage regulator for secondary side to connect ac power after 0 v, the ammeter without display; Then slowly increase the voltage regulator output voltage of secondary side, at the same time observe the ammeter, stay transformer secondary current of 10 a, stop adjustment, the voltage is about transformer primary side voltage rating of 5% ~ 10%.

If it's not ammeter, the voltage regulator to 30 v transformer output voltage can be. At this time, the rotor will have a current flows through the conducting bar, and in the surrounding magnetic field. In each sprinkle fine iron powder, conducting bar normal conducting bar edge will be evenly absorb iron powder, and break the iron powder on the little or no, this article can accurately find the micro variable frequency motor is broken.