Relay Testing and Commissioning Services
Solutions We Offer
Line Distance Relay
Transformer Differential Relay
Line Differential Relay
Directional Relay
ELECTRICAL TYPE PROTECTION RELAY TESTING:
Relay Functional/Operation Tests
Using Secondary injection kits we perform functional/Operation tests. In this test not only protection relay but all the equipment comprising protection scheme such as Master trip relays, Supervision relays, Auxiliary relays, Annunciators etc get tested. The functional tests consist of applying the appropriate inputs to the relay under test and measuring the performance to determine if it meets the specification. With the use of advanced Test Kits we can generate reports instantly. The kits software are equipped with some advanced features and in built test templates to facilitate very accurate test results.
Various Protection Schemes along with their specific characteristics can be Tested by means of these test kits like
Overcurrent Protection –
Under/Over Voltage Protections
Under/Over Frequency Protections
Rate of change of Frequency
Synchrocheck
Auto Reclosing
Directional Overcurrent Protection
Differential Protections for Line, Cable, Transformer, Generator, Motors
Distance/Impedance Protection for Lines, Cable, Generators
Generator Protections
Motor Protections
Busbar Protections
PERIODIC MAINTENANCE TESTS FOR PROTECTION RELAYS
Periodic testing is necessary to ensure that a protection scheme continues to provide satisfactory performance for many years after installation. All equipment subject to gradual degradation with time, and regular testing is intended to identify the equipment concerned so that remedial actions can be taken before scheme maloperation occurs. However, due care should be taken in this task, otherwise faults may be introduced as a direct result of the remedial work.
The self-checking facilities of numerical relays assist in minimising failures due to faulty relays. Defects in secondary wiring and incorrect connections are virtually eliminated if proper commissioning after scheme installation/alteration is carried out. The possibility of incorrect settings is minimised by regular reviews of relay settings. Network fault levels change over time and hence setting calculations may need to be revised. Switching and testing errors are minimised by adequate training of personnel, use of proven software, and well- designed systematic working procedures. All of these can be said to be within the control of the user.
The remaining three causes switching errors, application shortcomings, pilot wire faults etc. are not controllable, while two of these three are unavoidable – engineering is not science and there will always be situations that a protection relay cannot reasonably be expected to cover at an affordable cost.
Although protection equipment should be in condition when first put into service, problems develop unchecked and not revealed because of infrequent operation. With digital and numerical relays the in-built self-testing routines can be expected to reveal and annunciate most faults, but this does not cover any other components that, together, comprise protection scheme. Regular inspection and testing of protection scheme is therefore required. It is desirable to carry out maintenance on protection equipment at times when the associated power apparatus is out of service. This is facilitated by co-operation between the maintenance staff concerned and the network operations control centre.
