Datasheet

User Manual 990-9189A
DC MX06 60A Shelf Page 12 of 30 18
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FEB 02
2.3 Alarms + Customer Inputs
To monitor the system status a selection of alarm outputs are available. Each rectifier has 4 front panel
LED’s giving a visual notification of a system fault. There is also a range of open collector transistor
alarm outputs and a set of form C relay contacts that can be accessed at the rear of the shelf.
Below is a list of the available alarms along with their function and pin number.
2.3.1 System Alarms/Inputs
All the system alarms are available from the 26way ribbon connector (SK4) mounted on the alarms card.
The alarms and inputs are listed below.
The relay contacts are rated as follows:
AC Rating - 0.5A @ 125Vac
DC Rating - 1A @ 24Vdc
Max VDC - 0.6A @ 110Vdc
Alarm/Input Pin Description
V Trim SK4-13 This pin floats at 2.5V (O/P @ 54.5V) nominal with respect to
negative sense (SK4-15).
Applying a DC voltage adjusts the output by –1V/V.
(For 1V swing on program pin the output voltage changes by –1V)
+ Sense SK4-17 Bussed through sense pins from rectifiers.
- Sense SK4-15 Bussed through sense pins from rectifiers.
Rectifier Fail SK4-11 N/C relay contact bussed through from rectifier. Contact is closed
on fail
AC Input Fail SK4-24 Relay contact on daughter board. Contact closed when input
supply fails.
AC Input Healthy SK4-8 Relay contact on daughter board. Contact closed when input
healthy.
Common SK4-10 Common for all signals (unless stated otherwise). Signal common
and relay commons connected together
Enable SK4-19 Connects to SK29-2 (back-plane). To enable system output either
fit link from SK29-2 to SK29-3 (-Ve O/p) or connect SK4-19
(enable) to SK4-15 (-Ve Sense)
5V SK4-18 From internal rectifier rail. Low current capability supply to be
connected to Vtrim, to program down output volts.
Current Share SK4-12 Use for paralleling purposes only
Fan Fail SK4-9, SK4-1 Opto isolated open collector transistor output (rated at 60Vdc
@20mA). Pulls low when one or more rectifier fans fail (not
available if system fitted with Single LED Rectifiers).
SK4