Braking resistor on AC servo motor

[DavorKSM]

Braking resistor on AC servo motor driver is not working, and I cannot find power on it( It burned up), but I know it is 100ohm . Power on driver is 200W. Can I put 400w (100ohm) braking resistor on that motor?

 

[jraef]

Yes. It's the resistance that matters here. The 400W rating means it is capable of safely dissipating 400W, so if the servo drive is rated fro 200W, it cannot deliver more than that.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[cswilson]

Usually the servo drive manufacturer will recommend ratings, and often specific part numbers, for external braking shunt resistors. This should be in the manual for the drive.

It is common for these shunt resistors to have thermostats that can be wired into the drive, and the drive can fault if the shunt temperature gets too high. The intent is to keep the shunt from burning up. I don't know if your drive has this capability.

Be very careful in considering power ratings. The 200W drive rating is likely a continuous rating, with a peak rating several times higher. In most servo applications, the shunt resistor is for rapid decelerations, whose power requirements can be well above the continuous rating for a few seconds. The fact that you burned up your previous shunt means that you need to analyze your system requirements very carefully.

Curt Wilson
Omron Delta Tau

 

[DavorKSM]

Tnx