CMC 356-Related Products and Accessories1099.3.2 CMIRIG-BVia the CMIRIG-B interface box you can connect devices to the CMC 356test set that either transmit or receive the IRIG-B time reference signal(DC level shift protocol B00x). That way, two or more CMC test sets aresynchronized. Furthermore, an optional CMGPS synchronization unit canbe integrated into the test setup to serve as source of the synchronizationmoment or 1PPS signal, respectively. CMC 356 decodes (when receiving)or encodes (when transmitting) the IRIG-B protocol. The IRIG-B protocolextensions required by standard IEEE C37.118 are supported as well.The most significant functional enhancement of those Test Universe testmodules supporting the IRIG-B time reference is the starting andsynchronizing of CMC 356 states (signal output) with high accuracysynchronous to the IRIG-B 1 time reference or PPS/PPX 2 signal,respectively; for example for PMU synchrophasor tests.Figure 9-6:Typical test setup withCMIRIG-B(not true to scale)Requirements:• CMC 356 standard test set with Ethernet ports.• IRIG-B source or receiver with 5 V/TTL level; demodulated; DC levelshift protocol (B00x).1 IRIG stands for Inter Range Instrumentation Group and represents a serial time code format.2 PPS: pulses per secondPPX: programmable PPS signal (pulse rate, e.g., 1 pulse per minute or one pulse per10 seconds)Test signals (e.g., 3 x current, 3 x voltage).IRIG-B/PPS source, e.g. GPS receiver with IRIG-B output.IRIG-B/PPS receiver, e.g. protection relay, PMU.Optional CMGPS synchronization unit (depends on the application).12341234
