CALIBRATION

The calibration marks on the faceplate have a maximum

error of 10% and are provided only as guides. Proper

calibration requires using an accurate voltmeter in parallel

with the input signal. Use the following procedure to

calibrate your relay.

Unbalance

1. Adjust the UNBAL control fully clockwise and the

DELAY control fully counterclockwise.

2. Apply three-phase, nominal input voltage with the

proper phase sequence to the relay. The output relay

should energize.

3. Lower one phase of the applied voltage to the desired

trip level. Slowly adjust the UNBAL control

counterclockwise until the relay trips.

Delay

1. Set the DELAY control at the desired time setting.

2. Apply three-phase, nominal input voltage with the

proper phase sequence to the relay.