DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-361CABINET (Cabinet Sensors)
9
CABINET (Cabinet Sensors)
NOTE:
The CABINET maintenance object is valid only for multi -carrier cabinets.
For information about environmental maintenance on single-carrier
cabinets, refer to DC-POWER.
The cabinet sensors monitor cab inet temperature and fan rotation. Variable-
speed fans are used extensively in DEFINITY Systems.
The SYSAM c irc uit p ack in th e PPN ca bin et and the EPN Main tenan ce c irc uit
pack in a multi-carrier EPN cab inet monitor a temperature sensor (S1) at the top
of the cabinet and g enerate a major alarm if the exit air temperat ure exceeds 65
degrees Celsius (149 deg rees Fahrenheit). Another temperature sensor in the
top of the cabinet (S2) also monitors exit ai r temperature. If it exceeds 70
degrees Celsius (158 deg rees Fahrenheit), the power distribution unit turns off all
cabinet power and invokes emergency transfer . Other sensors monitor fan
performance.
The repair procedures that follow rely on your ab ility to distinguish b etween high
and low fan speeds b y the sound of the fans. Experience wi ll allow you to
distin guish between t he high a nd low pitches gen erated by high an d low speeds.
A thermometer is also required for some of the p rocedures that follow.
In making replacements, ob se rve the foll owi ng rules:
■New fan assemblies accep t
only
variable-speed fans.
■Old fan assemblies acc ept either variable-sp eed or nonvariable-sp eed
fans.
■Replace a fan assembly (c arrier)
only
with a fan assembly of the same
type (new for new, old for old).

Variable-Speed Fans

A variable-speed fan is identified by the fo llowing features:
■A fan and air filter assembly with p roduct cod e ED-67077-30, Group 4 or
greater, labeled on the front of the c arrier
MO Name (in
Alarm Log) Alarm Level Initial Command to
Run1
1. UU is the universal cabine t number (1 for PPN, 2 -44 for EPNs).
Full Name of MO
CABINET MAJOR test environment UU Cabinet Sensors
CABINET MINOR test environment UU Cabinet Sensors