2.3 Indicators
2.3.2.1 Power Tray Indicators
Figure 2–6 shows the ten indicators located on the DPU power tray rear panel.
These indicators provide information about the power tray. They all show the
status of some part of the power tray and are green during normal operation. If
a failure is detected, the corresponding indicator changes to red, and the power
tray shuts down. Any red indicators are latched ON, indicating the problem area,
and initiate the power shutdown.
Figure 2–6 Power Tray Service Indicators
MKV−040000314−55−RAGS
Chassis Ground
Temperature
Main Power Vcc +5 V
Main Power Vee −5 V
Main Power +12 V
Main Power −12 V
AUX Power Vcc +5 V
AUX Power Vee −5 V
AUX Power +12 V
AUX Power −12 V
Table 2–2 lists the function of each power tray indicator (from the top).
Table 2–2 Power Tray Service Indicators
PS Indicator
Function
Chassis Ground
Green — Normal
Red — Logic ground to chassis ground short; excess voltage
detection
Temperature
Green — Normal
Red — Excess temperature
Main Power Vcc +5 V
Green — Normal
Red — Failure in +5 V supply
Main Power Vee –5 V
ON — Normal
Main Power +12 V
ON — Normal
Main Power –12 V
ON — Normal
Auxiliary Power Vcc +5 V
ON — 15 A or 30 A breaker is set ON
OFF — indicates problem with power sequencer
Auxiliary Power Vee –5 V
ON — 15 A or 30 A breaker is set ON
OFF — indicates problem with power sequencer
Auxiliary Power +12 V
ON — 15 A or 30 A breaker is set ON
OFF — indicates problem with power sequencer
Auxiliary Power –12 V
ON — 15 A or 30 A breaker is set ON
OFF — indicates problem with power sequencer
DPU Controls and Indicators 2–9
