Siemens Micromaster 420 or MM420 Drive
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Jun 09, 2022 5:29 am
A0502 Overvoltage limit alarm in siemens micromaster 420 or MM420 drive - comes when the overvoltage limit value has been reached or high input supply voltage.
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Jun 09, 2022 5:32 am
Cause : Overvoltage limit Value - when the overvoltage limit value has been reached or high input supply voltage. The overvoltage limit value has been reached (actual value of the DC link voltage r0026 greater than r1242).
Diagnosis
1. if this alarm is permanently displayed, check the inverter input voltage.
2. is the DC link voltage controller (Vdc_max controller) de-activated (refer to parameter P1240)
3. short ramp times and/or large flywheel masses (moment of inertia)
Remedy
1. Check that mains supply voltage is within allowable range.
2. Increase ramp down times.
