Emerson NT5C06D - Manual (Page 38)

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