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Full Function Testing with the Square D S33595 Secondary Injection Test Set

Secondary injection testing is normally different to primary injection testing because it is normally conducted when the circuit breaker is closed but is not carrying any current through its main poles.

Secondary injection testing normally involves disconnection of the protective device from its normal VT/CT and connection to a specialist test set that can inject and measure/record the required operating signal directly into the protective device relay to cause it to operate the circuit breaker. The advantage of secondary injection testing is that the circuit breaker does not have to interrupt large current and only low voltage signals are injected to operate the device.

Square D S33595 Secondary Injection Test SetSecondary injection test kits are another piece of electrical test equipment that assists in testing the health of circuit breakers, and the Square D S33595 Secondary Injection Test Set is a full function test kit that is designed to perform tests on Micrologic, NT and STR Trip units.


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