# Altivar 71



## JRaef (Mar 23, 2009)

jtashaffer said:


> On a 15hp altivar 71 drive how do you set it up to run two vibe motors rated less than 15hp.


Same as with any drive. If the total FLA is less than the rating of the drive, just put it into V/Hz mode and get separate OL relays for each motor, with their aux contacts wired in series to an input that disables the drive if either one trips.


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## JRaef (Mar 23, 2009)

Took a look at an old manual I have. Should be that you run the OL aux contacts in series from the I/O board Common terminal to Input L16, then set Switch SW2 to "PTC". This is how you wire in an external OL device, as if it is a PTC thermistor in the motor. When the circuit opens, it's the same as the PTC thermistor going highly resistive and it shots down the output of the VFD immediately. You can then program the display to say "External Overload" in response to that input changing state.

You must also change it to V/Hz control for connecting multiple motors, the VFD cannot tune the Vector control with two separate windings. It's done in parameter set 1.4, select V/F 2pts:

​​​​*[V/F 2pts] *(UF2): Simple V/F profile without slip compensation. It supports operation with:
- Special motors (wound rotor, tapered rotor, etc.)
- A number of motors in parallel on the same drive
- High-speed motors​
- Motors with a low power rating in comparison to that of the drive


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