Nortel 7400 Hardware Installation page 395

The system does not supply power to the shelf if you turn on the power
before you install a CP. The power supply LED will remain red. If you are
using two power supplies, you must install at least one FP in addition to a
CP.
Note: Devices that use power supply models NTEP26CA and
NTEP27CA raise a minor alarm whenever the LED is green for one power
supply and a second power supply is set to standby. Other models may
also raise a minor alarm.
7 Verify that
• the power supply LED is green
• the cooling unit is operational
• the LED display on each FP is appropriate. See "Processor card LED
status display" (page 326)
• the cooling unit LED is green
• the power status indicator (top LED) on the front of the cabinet is
green (for cabinet installations only)
8 If necessary, apply power to a second power supply by setting its power
control to the on position. Verify that the power supply LED is green.
9 Verify that the appropriate LEDs are illuminated on termination panels.
See "Termination panel LED status display" (page 393)
Multiservice Switch 7400 Hardware Installation, Maintenance, and Upgrade 6.1S2
Chapter 39 Hardware procedures 395