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Option11C and 11C Mini TechnicalReference Guide
Reserve power

Discharge requirements

Reserve batteries must be able to provide 500 watts of power to each cabinet.
This is a worst-case figure based on the maximum power consumption per
cabinet.

Backup options

The options available when backing up the AC-powered Option 11C system
are as follows:
•Use customer-supplied batteries along with the NTAK28 breaker
assembly.
•Connect an Uninterrupted Power Supply (UPS) to the Option 11C
system.
•Use Nortel Networks supplied NTAK75 or NTAK76 battery units.
Customer supplied reserve batteries with NTAK28
Customer supplied batteries may be used as long they meet the requirements
set out in Table64. One NTAK28 breaker assembly is required per cabinet.
NTAK75 or NTAK76 battery units
Two battery units are available. The NTAK75 supplies a minimum of two
hours backup at full load, while the NTAK76 supplies a minimum of fifteen
minutes backup at full load.
CAUTION
Always follow the manufacturer’s instructions when installing
batteries.
Table 6 4
Reserve battery requirements
Sealed cells Cell float voltage String float voltage
23 2.30 — 2.36 52.95 — 54.25
24 2.20 — 2.26 52.95 — 54.25