Drive question-

[scrambled]

Tero-

I am in the process of redoing an older mill. It currenty has large working servos installed on it. They are 136 volts and rated at 6.5 ft lb continious and 26.3 ft lb peak.


Can the granite drive handle these?


These motors also have tachometers on them, would i just leave the wires off?


Thanks

Steve

[Xerxes]

I assume these are brush DC motors, aren't they? Do you have motor current ratings or torque constant value?

If current range matches drive, then there should be no problem using them.

Tachos are not needed, but incremental encoder is a must with VSD-E/XE.

[scrambled]

Tero

The continious amps is 6.1 , but the peak is 90 amps


What do you think?


Steve

[Xerxes]

Hmm, the peak vs continuous torque and peak vs continuous current ratio does not match. If 6.5 ft lb is produced at 6.1A, then 26.3 ft lb should be delivered at 24.4A.

Perhaps 90A is just a absolute maximum current before motor breaks and not meant to be driven purposely?

[scrambled]

That is what was on the data plate. I will try to find more informtion about the motor.


The z axis has a brake, can i just use a relay to control the brake or is there a better way?

Steve

[Xerxes]

If you use VSD-E in single axis mode, then it can connect brake coil to directly to drive. Brake will hold whenever drive is not controlling motor.

[scrambled]

Tero-

That is the plan. I have three vsd-e s that i am planning on using. How would i set it up using the relay?


Stevr

[born2bewilder]

If your motor brake is powered by 24v dc, and has a load of less than 800mA, you can use an external 24vdc power supply and connect to the on-board brake relay. Examine the VSD-E Manual, section 8.7, figure 13; and section 3, 'I/O characteristics'.

If the brake exceeds those ratings I think you could then use an external relay.