Nortel North American DMS-100 Instruction Manual page 75

Repairing and replacing NT3X90AA cooling units
35
36
37
38
At the PDC frame
39
40
DMS-100 Family NA100 Trouble Locating and Clearing Procedures Volume 2 of 2 LET0015 and up
Trouble locating and clearing procedures (continued)
If the FAN FAIL lamp
did not remain on when you dis-
connected the wiring to the air
flow sensor
Note: A FAN FAIL lamp that turns OFF when you disconnect the wiring to
the sensor indicates a sensor switch that has faults.
Remove the sensor switch.
Attach the replacement sensor switch to the switch bracket. Secure the
switch in position with screws, nuts, and washers.
Reconnect the wiring to the sensor switch, as noted in step 34.
Repeat steps 34 to 37 to check all sensor switches.
If the FAN FAIL lamp
is off
is on
DANGER
Possible arcing
Electricity can arc when you remove cooling unit fuses. Wear
eye protection.
Remove the fuses that power the inverters.
Do you have a blown fuse?
If a fuse
is blown
is not blown
Do
step 35
Do
step 62
step 85
Do
step 41
step 44
1-59
(continued)