Ntak76 Battery Back-Up Unit - Meridian Nortel 1 Option 11C Technical Reference Manual

Page 194 of 544
Table 59
Number of spares required (Part 2 of 2)
6.37
6.99
7.62
8.26
8.91
9.57
10.2
10.9
11.5
12.2
12.9
13.6
14.3
15.0

NTAK76 battery back-up unit

553-3011-100 Standard 14.00
Spares planning
NFT values
The batteries supplied with the NTAK76 have an average useful life of four
years, meaning the batteries are depleted to 80% of capacity, and backup time
is diminished. After this period of time the batteries should be replaced. For
more information refer to theOption 11C and 11C Mini Fault Clearing (553-
3011-500)The mean time between failures (MTBF) of the NTAK76 without
batteries is 370 years at 25
January 2002
6.99
7.62
8.26
8.91
9.57
10.20
10.90
11.50
12.20
12.90
13.60
14.30
15.00
15.80
°
C.
Number
of spares
17
18
19
20
21
22
23
24
25
26
27
28
29
30