The Model B-292 Secondary Injection Test Set is a single-phase test set specifically designed for testing the operation of the AC-PRO® and AC-PRO-II® micro-controller based trip units manufactured by Utility Relay Co. The test set can test pick-up and time delays of the various protection functions by driving current into the trip unit on the secondary side of the CT circuit. The test set will test 60, 50, 40 or 25 Hertz AC-PRO® trip units. (The AC-PRO-II® can be set for either 50 Hertz or 60 Hertz). The test set will test the AC-PRO® or AC-PRO-II® trip system with the exception of the CTs and associated wiring harness.