Access Power Solutions Installation Guide (APS6-400 Series)
8
Copyright © 2009-2010 Eaton Corporation. All Rights Reserved.
IPN 997-00012-53B December 2010
Battery Mid-point Monitoring Option (SC200 only)
Battery Mid-point Monitoring provides a cost-effective method for the early detection of
internal battery faults. The voltages of the two halves of a battery string are measured and the
system controller generates an alarm signal if a voltage imbalance is detected.
A voltage imbalance is an indication that one or more cells has an internal fault. Further
investigation can then isolate the faulty cell(s) and action can be taken to correct the problem
and prevent a total battery failure.
To connect the Battery Mid-point Monitoring option see details on page
. If a
String Fail
alarm
is generated see Troubleshooting on page
To ensure reliable operation Mid-point Monitoring operates only when the battery is in float
charge and after a configurable lockout period since the last battery discharge, Fast Charge,
Equalize or Battery Test.
Battery Time Remaining
The SC200 or SC100 obtains characterization data from either periodic battery discharges
(SC100) or every full battery discharge (SC200), to a specified end voltage.
During a battery discharge, the SC200 or SC100 uses this characterization data to calculate an
estimated time until the battery will reach the specified end voltage.
If a battery disconnect LVD is fitted then the end voltage will usually be the voltage at which the
LVD disconnects the battery.
Battery Time Remaining is designed for a constant power load. The accuracy of the time
remaining calculation will be reduced if the dc power system is connected to a predominantly
resistive (constant current) load.
The time remaining calculation will not be correct if a non-essential load is disconnected during
the battery discharge.
The following information is available about
Battery Time Remaining
.
Parameter
Description
Where to find:
Battery Time
Remaining*
During a battery discharge, this is the estimated time
until the battery voltage will be equal to the
End
Voltage,
at the present battery current.
Time Remaining
will be re-calculated if the load current varies during
discharge (for example, when a load disconnect LVD
operates).
SC200 or SC100: Menu >
Controls > Batt Time
Remaining
DCTools/Web: Batteries
Estimated State of
Charge (SOC)*
The estimated charge left in the battery (Ah).
*Values of Battery Time Remaining and SOC are only available during a discharge and if the
battery has been characterized
. The values will be N/A when the Battery Charge State is
Floating or Charge, or
if the battery has not been characterized.
See Battery Characterization.
For details refer to
Battery Time Remaining
in the SC200 or SC100 System Controller Operation
Handbook (see Related Information on page
