5.1.5 WATCHDOG CONTACTSUsing a continuity tester, check that the Watchdog contacts are in the following states:Terminals Contact state with product de-energised11 - 12 on power supply board Closed13 - 14 on power supply board Open5.1.6 POWER SUPPLYDepending on its nominal supply rating, the IED can be operated from either a DC only or an AC/DC auxiliarysupply. The incoming voltage must be within the operating range specified below.Without energising the IED measure the auxiliary supply to ensure it is within the operating range.Nominal supply ratingDCNominal supply ratingAC RMS DC operating range AC operating range24 - 54 V N/A 19 to 65 V N/A48 - 125 V 30 - 100 V 37 to 150 V 24 - 110 V110 - 250 V 100 - 240 V 87 to 300 V 80 to 265 VNote:The IED can withstand an AC ripple of up to 12% of the upper rated voltage on the DC auxiliary supply.Warning:Do not energise the IED or interface unit using the battery charger with the batterydisconnected as this can irreparably damage the power supply circuitry.Caution:Energise the IED only if the auxiliary supply is within the specified operating ranges.If a test block is provided, it may be necessary to link across the front of the test plugto connect the auxiliary supply to the IED.5.2 PRODUCT CHECKS WITH THE IED ENERGISEDWarning:The current and voltage transformer connections must remain isolated from the IEDfor these checks. The trip circuit should also remain isolated to prevent accidentaloperation of the associated circuit breaker.The following group of tests verifies that the IED hardware and software is functioning correctly and should becarried out with the supply applied to the IED.5.2.1 WATCHDOG CONTACTSUsing a continuity tester, check that the Watchdog contacts are in the following states when energised andhealthy.Terminals Contact state with product energised11 - 12 on power supply board OpenP446SV Chapter 24 - Commissioning InstructionsP446SV-TM-EN-1 617
