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Rockwell Automation Publication 1606-RM008A-EN-P - November 2021
DC-UPS - 24V, 20 A, 480 W Reference Manual
condition. According to the Eurobat guideline, design lives have been
structured into the following different groups:
•
3...5 years:
This group of batteries is popular in standby applications and
in small emergency equipment. This represents a 4 years design life with
a production tolerance of ±one year.
•
6...9 years:
This group of batteries is used when an improved life is
required. This represents a 7.5 years design life with a production
tolerance of ±1.5 years.
•
10...12 years:
This group of batteries is used when in applications where
longest life an 11 years design life with a production tolerance of ±1 year.
If the operational parameters differ from those that are specified for the
design life, an earlier replacement of the battery might be necessary. The “real
life” is called service life and is defined as the point at which the cell’s actual
capacity has reached 80% of its nominal capacity. At the end of the service life
the capacity degrades much faster, so that a further use of the battery is not
recommended.
The degradation of a battery begins with the production date and not with the
time when usage starts.
Effects, which shorten the service life of the battery and requires an earlier
battery replacement:
- Temperature:
The temperature has the biggest impact in the service life. The
higher the temperature, the earlier the wear-out phase of the battery begins.
The wear-out results in a degradation of battery capacity. See
. for
details.
- Number of discharging cycles:
The number and the depth of discharging
cycles is limited. A replacement of the battery might be necessary earlier than
the calculated service life if the battery exceeds the numbers and values of
.
- Overcharging and deep discharging:
Overcharging and deep discharging
shortens the service life and should be avoided. Due to the two individual
battery chargers and the temperature tracking feature of the 1606-XLS480-
UPS, the end-of-charge-voltage can be set precisely to the required value and
thereby avoiding unnecessary aging effects.
- Discharged batteries:
Charge retention is important to get the longest
battery life. Stored batteries that are not fully charged age faster than charged
batteries. Batteries that are not in use should be recharged at least once a year.
- High ripple voltage:
Excessive float charge ripple across the battery has an
effect of reducing life and performance. The 1606-XLS480-UPS does not
produce such a ripple voltage. This effect can be ignored when the battery is
charged with the 1606-XLS480-UPS.
