Relay testing

English Electric Relay test set.

Testing E.E. CDG relays on bench in workshop.
These protection relays are used in many NZ 11 kV substations.
Principle is based upon the ferraris disc system as used in kWh meters.
These relays are very reliable.

Testcurrents of twice, five and ten times the plug setting are applied, and timing tests done to trip.
Also the pick up and drop off currents are recorded.

The flag doesn't come up as the relay is not in service position from where an external 110 Volts supply operates the external contacts.