Nortel DMS-100 Series Maintenance Manual page 609

At the OPM cabinet
10
Use a voltmeter with 0.2% or greater accuracy to measure the voltage of
battery strings 0, 1, 2, and 3. Measure the voltage at the battery terminals,
not at the faceplate of the NT8X02 BCC card.
Note: If you enter this procedure from step 7, you are testing battery
strings 4, 5, 6, and 7.
The voltage must measure 50.4 V (80% capacity). If the voltage measures
less than 50.4 V, you must place the battery string in less than one month.
If measured voltage
is less than 49 V
OPM routine maintenance procedures
DANGER
Possible system damage
You can add or remove battery strings from an active OPM.
If you perform this action make sure the battery strings are in
the open-circuit state from the MAP terminal. Turn off the
associated battery charger controller card BCC NT8X02.
Connect or disconnect the battery cables at the back of the
cabinet. When you connect the affected battery strings,
return the battery strings to the load bus one string at a time.
If there is no MAP control, turn off the BCC before you
connect or disconnect any battery strings.
WARNING
Possible loss of service during battery replacement
Do not turn off more than one BCC NT8X02 at a time. If
you turn off more than one BCC NT8X02 service is lost if ac
power is interrupted. Turn off BCC0 when you perform
work on battery strings 0, 1, 2, or 3. Turn off BCC1 when
you perform work on battery string 4, 5, 6, or 7.
DANGER
Risk of batteries cracking
Disconnect the battery string immediately. If you do not
disconnect the battery string immediately the batteries can
crack before you install new batteries.
DMS-100 Family OPM Maintenance Manual XPM14 and up
Battery capacity tests
OPM
Do
step 11
13-7
(continued)