GE Multilin L30 Line Current Differential System 7-57 COMMANDS AND TARGETS 7.1 COMMANDS7be used. If both the PMU under test and the test set use the timing reference, they should be driven from the same IRIG-Bsignal: either the same GPS receiver or IRIG-B generator. Otherwise, the setpoints of the test set and the PMU measure-ments should not be compared as they are referenced to different time scales.Figure 7–2: USING THE PMU ONE-SHOT FEATURE TO TEST SYNCHROPHASOR MEASUREMENT ACCURACYCOLLECTING SYNCHRONIZED MEASUREMENTS AD HOC:The one-shot feature can be used for ad hoc collection of synchronized measurements in the network. Two or more PMUcan be pre-scheduled to freeze their measurements at the same time. When frozen the measurements could be collectedusing EnerVista UR Setup or a protocol client.