Rockwell Automation Chassis Models - Manual (Page 21)

Chassis Models October 2005 – Issue 4 21
Triguard SC300E Chassis Models
Area ‘g’ - Processor diagnostic ports
The connectors (26 pin IDC) in area ‘g’ are diagnostic ports, one for each processor; their
signals are the same as those available at the diagnostic ports on the processor front panels
(refer to the MPP User Manual 008-5100).
Areas ‘h’ - Power supply unit connectors
WARNING
Do not remove the clear plastic covers from the backplane areas ‘h’, the power supply
terminations they are protecting may carry lethal voltages.
Each area ‘h’ contains the connections at the rear of the related PSU, they are not normally
available and are protected by a clear plastic cover which should not be removed.
When ac power is used an AC Stud is fitted through the backplane at the top right of each area
‘h’ (viewed from the rear) to prevent DC Power Units being fitted.
Areas ‘j’ - Power supply status
Each area ‘j’ contains the alarm connector (Figure 2-8) for the adjacent Power Supply Unit
which enables remote, volt free alarm indications. The connectors are 4 pin Phoenix Combicon.
Pins 1 and 2 are connected across a pair of relay contacts which are normally open. During
normal operation the relay is energised and the contacts are closed but will open under fault
conditions such as:
Over temperature
Over or under voltage
Relay failure
Loss of input power
Pin 3 is linked to pin 1 and pin 4 is linked to pin 2 to duplicate the output.
The PSHARE LINK above the lower alarm connector carries a signal between the two power
units to enable power sharing so that both units carry an equal share of the load.