List of terms 81
Spare stock size
The quantity of spares for a given stock item.
Sparing interval
The period of time that stocks of replaceable SL-1 items should last without
being replenished.
Stock confidence level
The allowed probability of not being out of stock when the sparing interval
of one year is greater than 99. 9 percent.
System hardware
Hardware configuration.
System monitor
A microprocessor-based circuit pack used to monitor the UEM (Universal
Equipment Module) power supplies, stack thermal status, and fan operation
status. Each system monitor reports its status to the system CPU, and the
head (master) system monitor checks their statuses. The master system
monitor will trip the stack circuit breaker in the event of a problem
(excessive temperature, for example).
TCM
Time Compression Multiplexing.
TDS
Tone and Digit Switch.
Time Division Multiplex (TDM)
Combining two or more information channels into a single transmission
channel by assigning each information channel an exclusive periodic
transmission time interval. (See “Multiplex: and “Frequency Division
Multiplex.
“)
Top cap
A drip-proof cover for the UEM (Universal Equipment Module). It
provides airflow exits, RF/EM1 shielding, I/O cable entries/exits, and
overhead cable-rack mounting.
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Three-Port Extender.
System overview 553-3001-100
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