Home > Knowledge > Content
The novice can solve the frequency converter common fault diagnosis and processing.(3)
- May 04, 2018 -

1.2 damage to the rectifier bridge.

1.2.1 judgment

It can be judged by the electric barrier of multimeter, and the connecting piece is released to the rectifying bridge in parallel, and the bad one is found.

1.2.2 cause of damage.

(1) the device itself is of poor quality.

(2) the damage of the backstage circuit and the inverter power switch device leads to the damage of the rectifier bridge over the short-circuit current.

(3) the power grid voltage is too high, and lightning and overvoltage surge occur in the grid.The power grid has small internal resistance, and the voltage sensitive resistance of the overvoltage protection has been destroyed, causing all the overpressure to be added to the rectifier bridge.

(4) the inverter and the power grid power transformer is too close, in the middle of the line impedance is very small, inverter dc reactor and the input side is not installed ac reactor, the rectifier bridge in capacitance filtering the impact of high amplitude peak pulse current condition, causing premature failure rectifier bridge.

(5) the input of the missing phase makes the bridge burden heavier and damaged.

1.2.3 replacement

(1) find the root cause causing the damage of the rectifier bridge, and eliminate it to prevent the new rectifying bridge from being damaged again.

(2) replace the new rectifier bridge, and ensure that the welding rectifier is reliable.Ensure the electrical safety spacing of the surrounding components, screw the connection to tighten, prevent contact resistance large and hot.Conductive heat conduction with the radiator requires the coating of silicone grease to reduce thermal resistance.

(3) for the parallel rectifier bridge, the same type and the same manufacturer's products should be used to avoid the damage of the current unevenly.

32.jpg