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

Models: NT5C06D

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