A thermal overload relay disconnects the power line to the motor during a motor overload condition to prevent damage to the motor.

Install a thermal overload relay between the drive and motor in these conditions:

  • When you operate more than one motor with one drive

  • When you operate the motor directly from the power line with a power line bypass

When you operate one motor with one drive, it is not necessary to install a thermal overload relay. The drive has electronic motor overload protection in the drive software.

Note:

  • When you install a thermal overload relay, set parameter L1-01 = 0 [Motor Overload (oL1) Protection = Disabled].

  • Set up a sequence that will trip an external fault (coast to stop) for the contacts of the thermal overload relay.