I have a question regarding Danfoss frequency converters
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Three Danfoss frequency converters were installed on site, but after each pump shutdown, an alarm for DC circuit overvoltage A7 would appear on the frequency converters. How can this be resolved, or how can this alarm be disabled?
I have not used Danfoss inverters before, but there are generally only two reasons for overvoltage on the DC bus: one is an excessively high input voltage, and the other is back-feeding from the load. Your case likely falls under the second category. Check the shutdown method of the inverter, change it to free shutdown, try setting a longer ramp time, or install a shutdown resistor
Thank you, I’ll give it a try. I think it’s also the second possibility
After each pump shutdown, overvoltage in the DC circuit appears on the inverter; this is likely due to the short shutdown time, which results in energy being reflected back by the motor. As mentioned on the 3rd floor, it is recommended that the parking time be increased, or that braking resistors be added to dissipate energy.