This is the 22 Channel version of the 40-202 Fault Insertion Switch. It is primarily designed for the simulation of fault conditions in automotive & avionics applications involving the reliability testing of safety critical controllers. It is designed to be able to insert three different fault conditions between the test fixture and the equipment under test: Open-Circuit Short-Circuit between UUT connections Short-Circuit to other signals such as Power, Ignition & Ground via Fault Insertion Bus Relays in-line with the signal paths allow open circuit conditions to be simulated on either side or both sides of a signal pair. Relays between each channel pair enable adjacent signals to be shorted, and relays between signal paths and the Fault connection allow the application of external fault conditions. The switching topology of the 40-202 allows switching channels to be interconnected so that complex fault insertion systems can be constructed. Supported by eBIRST eBIRST switching system test tools simplify switching system fault-finding by quickly testing the system and graphically identifying the faulty relay.