Emerson NT5C06D Input AC voltage monitor, Thermal shutdown, Remote high voltage shutdown

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38 Operation

Input AC voltage monitor

The rectifier monitors the input voltage, inhibits its operation and sends an RFA when the AC voltage decreases below 176 or rises above 264 V AC. An AC FAIL alarm contact is transmitted through the signal connector.

The rectifier recovers its normal operation automatically when the input voltage returns within the acceptable limits, without any operator intervention.

Thermal shutdown

The rectifier protects itself against thermal over stress by inhibiting its operation for the duration of the high temperature condition. The RFA alarm is triggered.

Remote high voltage shutdown

In addition to the local high voltage shutdown feature, the power plant controller can shut down any rectifier by sending a high voltage shutdown signal, ground (BAT RTN) pulse. The rectifier will shut down within 50 ms if it is supplying more than 3 A +/- 0.75 A.

Local / remote high voltage shutdown reset

The rectifier may be reset from an HVSD condition either by toggling the rectifier’s AC circuit breaker, or by applying a ground signal at the HVSDR input of the rectifier, provided that the 'TR' lead is not activated.

If the HVSD condition subsides the rectifier will restart automatically. If a second HVSD event occurs within a 5-minute interval the rectifier will lock out on the second event and have to be manually or remotely reset to restart.

Remote equalize control

The rectifier is equipped with remote equalize control. This control is operated by applying a remote ground signal (BAT RTN) and returns to normal (Float) operation upon removal of the signal.

Power interface edge connector

The rectifier AC, DC, and chassis ground interface is done through the power interface edge connector. This connector is designed to establish the frame ground connection first. Figure 10 shows the rectifier to shelf power interface connections.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

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Contents Helios Rectifier 25/48 Single Phase -48V, 25 a P0831010 Standard 7.00 MayPage Helios Rectifier 25/48 Single Phase -48V, 25A Page Publication history This page is left blank intentionally Contents Contents Shelf List of ProceduresList of Figures List of TablesThis page is left blank intentionally Introduction DescriptionEquipment Identification MPS75 NT5C10CX  power shelf 23-inchApplications MPS75 Modular Power Shelf-NT5C10C with 8-pin signal cables NT5C06D Switch Mode Rectifier Electrical specifications SpecificationsElectrical specifications Reliability Efficiency and Power FactorOutput noise and ripple Heat DissipationStorage Environmental specifications OperatingTransportation Specifications Tools and test equipment Installation and start upInstalling the power shelf Wiring the power shelf Procedure 1 Installing the power shelf Step ActionAWG for each rectifier Installing the AC powerAC cable wire size Max for each rectifierDC Conductors Installation Power shelf individual AC connectionControl and Alarm Connections Connecting the DC power shelfRectifier 2 fail alarm Rectifier Failure AlarmRectifier 1 fail alarm Rectifier 3 fail alarmDC Circuit Breaker AC Line Fail AlarmFan Alarm Sense FailA0384387 SIG NAL Cables FRO M Shelves Verification Installing the rectifierFactory setting Float Voltage Adjustment Procedure 4 Starting up the rectifier StepHigh Voltage Shutdown Hvsd Adjustment Rectifier meter accuracy= 52.2 + .15 V = 52.35 Load Sharing Ii Forced ShareCurrent Limit Verification CL Slope Load Share Load Share Adjustment ProcedureProcedure 5 Adjusting the load share Step Action Forced Load ShareOperation Local float / equalize control FeaturesFront panel controls High voltage shutdown Hvsd localRectifier failure alarm RFA Start-up delayIndicators Fan failure alarmRemote ON/OFF control Sense fail alarm SEN FailLocal ON/OFF control AC breaker Remote voltage sensingDischarge of output capacitors Sequential startParallel operation Input AC voltage monitor Local / remote high voltage shutdown resetPower interface edge connector Thermal shutdownSignal interface connector Power interface connectionsControl signal connections Float / equalize MaintenanceProcedure 6 Adjusting the float / equalize Step Fan failure High voltage shutdown HvsdCooling fan Fan replacement NT5C06D rear view Power shelf This page is left blank intentionally System fault diagnosis Fault symptom Possible causes TroubleshootingAlarm indication RFA fault Current or voltage float fault SEN Fail faultErratic load fault Fault symptom Possible causesAppendix a Replacement parts CPCAppendix a Replacement parts Country Appendix B Technical service assistanceLocal toll-free prefixes United States Canada Europe Asia and the Pacific Appendix B Technical service assistanceToll-free technical assistance numbers List of terms and acronyms Northern Telecom Rectifier Fail AlarmNormally Open Sense FailPage Part of Emerson Network Power