PROBLEM:
This frequency inverter is interesting because it is of very high power (about 35kW) – it belongs to older generations of the device, but is still a favorite among companies for its German robustness and quality. Its malfunction was the constant showing of a “short circuit” at the output, although it was not connected to any motor, nor was there any load.
SOLUTION:
The IGBT module in the device was destroyed because the output lines were not properly connected to the motor (human error). The strange thing was that, despite the quick reaction of the fuse, the output IGBT module had still burnt out. Also destroyed was the control of output current with the parts working on the principle of the Hall Effect.
TESTING OF THE REPAIRED DEVICE
WHAT THE VIDEO SHOWS:
The video shows the first testing of the device (“does it even work”) with the PC control system. The German manufacturer created a great software for quick and simple control of the inverter and thus made the job much easier. After this testing, due to it very high wattage, the device was submitted to additional testing with artificial loads and loading in order to test all of the aspects of the device, variations of voltage, power, response to loadings etc.