Can i calculate motor torque in real time by using "Read DAC.vi"?

[wlan]

Hello!

I´m using PXI-7358, UMI-7774 to control Faulhaber servo motor 2036U 012B (together with the amplifier Faulhaber BLD 5603 CC4P, current control modus).

In my application, i should monitor the torque of the motors.

"Read DAC.vi" is used to monitor the output command from the PID loop. When the DAC output is connected to a torque block servo amplifier, you can use this value to calculate motor torque or to monitor the acceleration and deceleration portions of a trajectory to see how close the control loop is to saturating at its maximum torque limits. (from NI-Motion VI help)

But how? I can get the DAC value (in Voltage), i have torque constant and No-Load-Current. But where can i get the so-called "Amplifier Gain" (Ge), in order that i can convert voltage value to current value?

Can somebody help me?

Thanks a lot!

WLAN

[Brian_Beal]

From the spec sheet for the amplifier, it appears that 5 volts scales to 4 amps.

[AnalogKid2DigitalMan]

It's in your manual, page 7:

http://www.faulhaber-group.com/servlet/com.itmr.waw.servlet.FileViewer?sprachid=1&kid=41656&pid=1201...

0.6 or 1.2 A/V (Transconductance gain)

Hope this helps

[AnalogKid2DigitalMan]

Brian:

Looks like we have conflicting information

[AnalogKid2DigitalMan]

For the 5603, I think the correct answer is 0.6 A/V. With 5V max command voltage, max output current will be 3A. Looks like the 4A specified is a safety cycle-to-cycle current limit.

[wlan]

Hello Brian and AnalogKid,

Yes, i think 0.6 is the right gain i need!

Thanks for your help!

WLAN