Nortel Passport 15000, Hardware Installation And Maintenance, Page: 762 / 874

762 Chapter 17 Hardware procedures
241-1501-240 5.2S2
Removing an upper cooling unit
Remove an upper cooling unit to access the cooling unit parts for
replacement, or to replace the entire cooling unit.
Prerequisites
• You must be familiar with “Safety considerations and best practices”
(page 53).
• You need a driver for the thread-forming 10-mm (3/8-in.) hex-head
screws that fasten each cooling unit to the frame or rack.
• You need a helper to hold the unit until it is fastened because it weighs
(9.1 kg or 20 lbs) and tends to slide out of position when it is unfastened.
CAUTION
Service degradation or interruption by heat
When the cooling unit of an in-service Passport 15000 or
20000 loses power, the air temperature inside the shelf
rises rapidly. When the temperature inside a fabric exceeds
70 degrees Celsius (158 degrees Fahrenheit), that fabric
will automatically shut down until the temperature drops
below the threshold.
WARNING
Risk of injury by fan blades
While working on any equipment near the cooling unit
fans, be continuously aware that the rpm of a live fan can
suck loose clothing, hair, or jewelry into the fan blades or
amputate a finger. Do not touch a live fan with anything.
WARNUNG
Verletzungsgefahr durch Lüfterblätter
Beim Arbeiten in der Nähe der Lüfter des Kühlaggregats
besteht die Gefahr, daß ein rotierender Lüfter lose
Kleidung, Haare oder Schmuck in die Lüfterblätter saugt
oder einen Finger abtrennt. Berühren Sie einen Lüfter
niemals, weder direkt noch indirekt.