Specifications

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DX-120 Installation and Maintenance Manual OVERVIEW
Specifications (continued)
MTBF (MEAN-TIME BETWEEN FAILURE) DATA
Mean-Time Between Failure Analysis
System Components
Cabinet Assembly 86.0
Power Supply Unit 170.0
CPM 2,915.7
408M 11,407.3
DPM8 3560.8
DPM16 121,654.5
COM4 6,146.5
APM4 6,860.2
MDM 761.0
AAM 2,337.3
T1 318,076.27
ISDN (T1/PRI) 257,340.64
Method:
Use the figures above for each unit installed (or to be installed)
and calculate the total for this system configuration.
Use the total from step 1 in place of the variable “x” in the formula
at the right to calculate MTBF for this system configuration.
(1 ³ )x(109) = MTBF hours