DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-362CABINET (Cabinet Sensors)
9
■A five-pin white connecto r mounted next to each fan on the fan assemb ly
cover plate for speed control and alarm c ircuitry
■A two-pin black -48 V powe r connector to each fan
■A power filter (ED-1E554-30, G1 or G2) located in a metal b ox mounted
behind the fans on the right-ha nd cable trough as you face the rear of the
cabinet
■The AHD1 circuit pack and the two S4 sensors used with older fan
assemblies are
not
present.
Alarm leads from each fan are tied together into a single lead that registers a
minor alarm against CABINET whenever a fan’s speed d rops below a preset limit
or fails altogether.
NOTE:
The front fans may run at a different speed than the rear fan s since they are
controlled by d ifferent sensors.
Replacing Variable-Speed Fans
This procedure app lies to replacement of a variab le-speed fan (KS-23912, L3) in
a new type fan assembly (ED-67707-30, G4 or greater). Do
not
use a
nonvariable-speed fan in this assembly.
1. If replacing a fan in the front of the c abinet, remove the white plastic fan
assembly cover by p ulling it outward. There is no cover on the rear fans;
they are accessible simp ly by opening th e rear cabinet doors.
2.

Connect the grounding wrist strap to yourself and the c abinet.

The fan
alarm circuit can b e damaged b y ESD.
3. Disconnect the white 5-pin connector on the fan assemb ly.
4. Loosen and remove the retaining sc rew nearest the power connector on
the defective fan.
5. Disconnect the 2-pin b lack power plug on the fan.
6. Loosen and remove the other retaining sc rew on the fan.
7. Remove the fan from the fan assembly.
8. Position the new fan and insert the screw that is op posite the power
connector.
9. Connect the 2-pin blac k power plug on t he fan.
10. Connect the white 5-pin co nnector on the fan assembly. Insert and ti ghten
the retaining screws.
11. Replace the front fan cover, if removed .