3
5. Operation
PowerSafe SBS XC monoblocs and cells are specifically designed for cyclic unreliable
grid applications where, due to the demands on the battery, there is a high risk of
uncontrolled partial state of charge operation.
The battery will give the best performance and service life when working at a
temperature of 20°C. The maximum operating temperature range is -40°C to +50°C.
5.1. Float Voltage Operation
Constant voltage chargers are recommended. The charging voltage should be set at the
equivalent of 2.29Vpc at 20°C / 68°F.
The recommended float voltage temperature compensation is:
•
2.29Vpc +3mV per cell per °C below 20°C
•
2.29Vpc -3mV per cell per °C above 20°C
5.2. Fast Charge Operations
The inherently high charge acceptance of TPPL Technology used in the PowerSafe
SBS XC is suited for applications which require a fast time to repeat duty, in such
applications the rectifier voltage should be set at 2.35Vpc to 2.40Vpc at 20°C.
Once fully charged the voltage can be changed to float voltage with temperature
compensation as required.
Further details can be found in our PowerSafe SBS XC Operating Guide for Unreliable
Grid Applications.
5.3. Charging Current
Due to their very low internal resistance PowerSafe SBS XC batteries will accept
unlimited current during recharge. However, for cost and practicality purposes in float
applications where minimizing recharge time to support repeat duty is not critical, the
rectifier current can be limited to the load plus 0.1C
10
Amps (minimum).
5.4. Discharging
Batteries must not be left in a discharged condition after supplying the load but must
immediately return to recharge mode.
Failure to observe these conditions may result in greatly reduced service life.
5.5. Accidental deep discharging
In order to protect the battery it is advisable to have system monitoring and low voltage
cut-out. A low voltage disconnect of 1.93 Vpc (80% DoD) should be applied to protect
the battery from abusive over discharge.
Abusive deep discharge can result in premature deteriation of the battery and a
noticeable reduction in the life expectancy.
5.6. Effect of temperature
Operation of valve regulated batteries at temperatures higher than 20°C will reduce life
expectancy. Life is reduced by 50% for every 10°C rise in temperature.
5.7. Unreliable Grid Operation with high risk of Uncontrolled Partial State of
Charge
The high charge acceptance capability of PowerSafe SBS XC monoblocs and cells allows
the use of fast charge techniques. This enables the battery to be brought towards full
state of charge quicker and having greater battery capacity available in the event of
further power outages. Where power outages are frequent PowerSafe SBS XC can be
operated in partial state of charge conditions. It is very important to return the battery
to full state charge to ensure it does not suffer from reduced performance due to the
build-up of irreversible sulphation.
Once the battery is brought to full state of charge the voltage setting should revert to
float voltage, with temperature compensation applied, in order to prevent prolonged
periods of overcharge.
Further details can be found in our PowerSafe SBS XC Operating Guide for Unreliable
Grid Applications.
6. Data Recording
It is recommended that as a minimum, the following information be recorded by means
of regular data logging – which the user must make available to EnerSys® to validate
any warranty claim,
1) Records of the commission charge.
2) The number of cycles performed and the depth of discharge (“DoD”) of each cycle.
3) The duration of each discharge and charge cycle, and the Ah in and out (Wh in and
out).
4) Full details of the recharge voltage/current profile for the last 50 cycles.
5) A full history of the ambient and battery surface temperatures, recorded at regular
intervals throughout battery operation and life.
6) The time and date of each “event” (an “event” is defined as the start/stop of the
battery discharge, the start/stop of the battery recharge, the start stop of any
generator input power or other input power source, etc).
Contact EnerSys if you have any questions regarding maintenance.
7. Disposal
PowerSafe SBS XC batteries are recyclable. Scrap batteries must be packaged and
transported in accordance with prevailing transportation rules and regulations.
Scrap batteries must be disposed of in compliance with local and national laws by a
licensed or certified lead acid battery recycler.
PowerSafe
®
SBS
®
XC
EN
