This is a test to check the maximum length of time that the protection relay can withstand an interruption in the auxiliary supply without de-energizing, e. switching off, and that when this time is surpassed and it does transiently switch off, that no maloperation happens. Since the basic function of a protection relay is to correctly function under abnormal. Verify instantaneous pickup setting for motor protection relay blocks motor starting current but clears high-level faults Relay calibration drift causes cascading failures: a relay set to operate in 0. 8 seconds allows fault damage to propagate upstream, tripping feeder. Megger's smart relay testing solutions and expert support help you validate protection performance, improve system reliability, and ensure continuity of power across your network.