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Page 202 of 544 Power supplies
553-3011-100 Standard 14.00 January 2002
PFTU operation
Power is switched over to the Power Fail Transfer Unit (PFTU) during any of
the following conditions:
• The CPU sends a signal to the PFTU
• A power failure occurs
• A CPU failure occurs
• The PFTU is manually activated
• The fiber link to an expansion cabinet fails (PFTU for that cabinet only)
The Option 11C power supply connects to the PFTU through the AUX
connector at the bottom of the main cabinet, and in each expansion cabinet.
Table 63 provides the pinouts at the cross connect terminal for the Auxiliary
cable.
Table 63
Auxiliary cable pinouts
Cable Signal
BL-W 1 Dot BRTN
BL-W 2 Dot BRTN
O-W 1 Dot -48 V AUX
O-W 2 Dot PFTS
G-W 1 Dot -15V AUX
G-W 2 Dot +15V AUX
BR-W 1 Dot -
BR-W 2 Dot -