Battery Rotation And Testing Audit - Nortel DMS-100 Series Maintenance Manual

The voltage can drop to –47 V or less than –47 V. If this event occurs the
system generates a PES104 log report with the message
. The load conditions determine the amount of reserve power that
voltage
the batteries have. The batteries can have 1.5 to 2 hours of reserve power.
When the batteries reach –42.5 V dc, the BCC disconnects the batteries from
the load bus.

Battery rotation and testing audit

The OPAC battery rotation and testing audit, which runs every hour, controls
and monitors the OPAC automatic battery rotation. During an ac failure, the
audit increases every 15 min. The audit increase does not effect battery
rotation because no rotation occurs in the ac failure mode.
Intermittent charging scheme
The OPAC uses an intermittent charging scheme that the battery rotation and
testing audit implements. Do not confuse the OPAC intermittent charging
scheme with the float or cyclic charging schemes. These schemes are
referred to in other battery application manuals. A description of each
scheme follows.
A float charging scheme applies a constant voltage to the batteries to
keep the batteries charged. The scheme also recharges the batteries after
discharge, and prevents accumulation of sulfate deposits on internal
battery plates.
A cyclic charging scheme means that the batteries are discharged
between each charging cycle. The OPM batteries experience a deep
discharge in the OPM during extended ac outage.
An intermittent charging scheme maintains the batteries on the system
load bus at a voltage just above the battery open circuit voltage. This
voltage is –50 V dc for the Eagle-Picher battery.
This voltage can maintain batteries in a complete charged state. This
voltage is also enough to recharge the batteries to between 90 % and
100 % after a discharge. This voltage is not enough to prevent
accumulation of sulfate deposits on battery plates. The batteries are
moved from the load bus to the charge bus for a short period of time.
Charge bus voltage is enough to make sure the batteries are charged to
full capacity. This voltage forces sulfates that accumulate on the battery
plates back to the battery liquid.
DMS-100 Family OPAC Maintenance Manual XPM12 and up
OPAC maintenance overview 2-43
load bus low