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Appendix 2
BA491 Replacement Battery
A2.0 BA491 intrinsically safe battery
The BA491 is an intrinsically safe ATEX
component approved replacement battery for
use in BEKA associates intrinsically safe and
safe area products.
At 20
o
C the BA491 battery only loses about
one percent of its charge each year allowing
replacement batteries to be stored on-site.
Because of this long shelf life and the very
small current consumed by the BA344D rate
totaliser replacement batteries should be
conditioned before being installed.
A2.1 Battery conditioning
When not being used an insulating oxide layer
forms on the internal battery electrodes that
prevents self-discharge and results in the very
long battery shelf life. The very small current
consumed by the BA344D rate totaliser may
not be sufficient to quickly break down this
oxide layer which will result in the instrument
not functioning immediately it is switched on.
When a replacement battery is fitted, or when
the rate totaliser is turned on after not being
used for an extended period, the battery should
be conditioned by drawing a relatively large
current from it for about thirty seconds to break
down the oxide layer.
Do not leave the resistor connected as this will
discharge the battery and shorten its life.
The amount of current drawn is not critical,
carefully plugging a resistor with a value
between 0 and 50ohms into the battery output
terminals for about thirty seconds will break
down the oxide layer and condition the BA491
battery – see Fig A1.
A 27ohm resistor is supplied with all
replacement BA491 batteries.
A2.2 Disposal of used batteries
The BEKA BA491 battery contains
Lithium
Thionyl Chloride cells that should not be
included with standard industrial waste or
incinerated.
More information about disposal is available
from The British Battery Manufacturers
Association www.rebat.com
Fig A1 Conditioning BA491 battery by
plugging a resistor into the output
terminals for about 30 seconds.
Summary of Contents for BA344D
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