COMBITEST system for relay testing

COMBITEST provides a safe, secure, and easy-to-use method of secondary injection testing of a protection system when performing commissioning and maintenance when used in conjunction with Hitachi Energy’s Intelligent Electronic Devices.

In a test it is possible to inject signals to the isolated relay in order to observe its performance and operation limits. Problems may thus be discovered before an actual protection operation is called for. A safety feature in COMBITEST is that CT shorting is automatic upon insertion of the test handle into the test switch. No external shorting links are needed on the test handle. Trip circuits are interrupted prior to CT shorting during insertion of the test handle.