Protective Relay Testing

 

Protective relays monitor critical electrical and mechanical quantities and initiate emergency shutdown when they detect out-of-limit conditions. Protective relays must detect abnormal conditions, shut down appropriate equipment, and must not incorrectly operate and unnecessarily shut down equipment at any other time.

Protective relays need to be tested to avoid its fails to act during a fault, relay coordination, its adaptability to latest power system as many feeders an loads might have got added over the years after the relay was installed.

 

Our type of services in relay testing are as follows: 

A. Acceptance Testing

Relay acceptance testing proves a relay is good right out of the box. This testing insures no damage has occurred during shipment, and that there are no manufacturing defects.

 

B. Commissioning

A field test to determine the relay functions accurately in the environment in which it’s installed. Actually this starts at the point of procurement. The specs will be matched with the submitted drawings from the suppliers. Finally after installing it checks:

  • Accuracy of assembling the components in relay
  • Ratings
  • Calibration
  • Conformity with entire system

 

C. Periodic Maintenance Testing

After a relay is commissioned it’s important to carry out regular maintenance tests. Some of the advantages of such testing can be stated as, it will pin point a defective relay before it fails to act during a fault, relay coordination, its adaptability to latest power system as many feeders an loads might have got added over the years after the relay was installed.

The test results can then be audited and used for decision making with respect to system integration and to avoid relay problems in the future.

  • Operational test/Trip test- Checks functionality of I/O logics with respect to design.
  • Calibration Test-Verifies the relay operation is within its trip time and pick up current tolerances.
  • Alarm test-checks the functioning of Alarm, which is to notify of the errors in the internal circuit.