1-66 Trouble locating and clearing procedures (continued)
297-8021-544 Standard 14.02 May 2001
Repairing and replacing NT3X90AB cooling units
(continued)
Repairing and replacing NT3X90AB cooling units
At the FSP
1
To silence the alarm, turn ON the FAN FAIL OVERRIDE switch.
At the frame
2
Remove the air intake grill and filter assembly from the front of the cooling
unit.
3
Determine if the FAN FAIL lamp darkened on the frame supervisory panel
(FSP) when you removed the filter.
4
Remove the filter and grill to a location away from the switchroom. Use a dust
cloth and vacuum to clean the fan air intake.
5
Vacuum or wash the filter in soap and water, according to the filter type.
6
Replace the filter in the grill and reinstall the filter in the cooling unit.
7
Turn OFF the FAN FAIL OVERRIDE switch.
8
Go to step 79.
At the PDC frame
9
Remove the fuses that power the inverters.
DANGER
Next level of support
The cooling unit configuration in the frame can differ from
the following description. If you encounter an important
difference, contact your next level of support.
If the FAN FAIL lamp
Do
darkened
step 4
remained on
step 9
DANGER
Possible arcing
Electricity can arc when you remove cooling unit fuses. Wear
eye protection.