Motor Over Temperature Fault in SINAMICS V20 Drive connected to High speed Spindle Motor

Hi All,

Thank you in advance for all your help.

I have a SINAMICS V20 Drive which is connected to a 2.0 Kw , 14 A, 400 Hz, 24000 RPM Spindle Motor.

I have used the motor Identification function and set all the parameters, but still after using the motor for about 2-3 hrs i get a "Motor Over Temperature " F11 Fault, and the VFD shows motor temperature to have reached 145 degree Celsius.

I still cant seem to solve the problem even after moving the Machine to an AC environment.

How can i solve this problem??

I assume the drive is properly sized?

Double check if the motor data is entered correctly.

Check if the motor is really hot.

What is the control mode type?

Did you try turning voltage boost off (p1310)?

You have to understand that said error has to do with temperature which is calculated (by means of I2t) not measured - that's why moving it to AC cabinet won't change a thing (fault wise)

What you should really do or have done is use a motor equipped with a PTC so you'd know what's the real motor temperature.

Hello Sir,

The  drive is properly sized,  I've checked the data again, the motor isnt really getting hot and the control mode type is set to default, V/f with Linear Characteristics.

We haven't  tried turning the P1310 Parameter off, but what exactly does this parameter do? and can i change it from a 50% to 0%

The motor does have a PTC but nothing except "PTC-130 Degree Celsius" is mentioned in the manual, no mention as to what it is whether analog or digital and what has is to be connected, and we havent worked with a motor having a thermister before.

Anything here would help.

Thank you 

That's great.

Please see related FAQ: SINAMICS V20: connecting a motor temperature sensor (PTC/KTY).

After properly connecting the PTC and setting relevant DI as external fault as described in the FAQ you can set P0610 = 0, this will DISABLE reaction for I2t monitoring.

You'll be stripped of software protection against overtemperature but as you can see in your case it's not working properly - common case with the spindles. 

PTCs resistance will spike above 130C and trigger a fault in the inverter.

If you don't feel confident about it you can instead try setting P0335 (motor cooling) to 1, this will fool V20 into thinking there is a separate fan cooling the spindle - therefore the calculated I2t will be lower.

Another solution could be adjusting the motor weight to adjust motor temperature model.

Anyway - the most important thing is to connect the PTC and set the relevant DI as external fault and then using one of the possibilities described above fool the inverter or just shut the I2t protection down.

Sir,

I have done everything that you said, both the VFD are working fine now, fault inputs also are available in the PLC, hope the fault doesn't occur again.

Thank you for all your help. 

New question published by Ammuu is split to a separate thread with the subject V20 shows F11 error and the motor stop instantly.

Best regards
Jen_Moderator