Snorkel S2646, Manual

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S2646/S3246 Maintenance – 17
11. Batteries should not be discharged below 20% of
capacity (approximately 1.8 volts per cell under nor-
mal operating load; 1.98 volts open circuit; 1.145
specific gravity). Proper battery sizing will help avoid
excessive discharge.
12. Battery chargers should be sized to fully charge bat-
teries in an eight hour period. Chargers should be
kept in proper operating condition.
13. Do not use a mismatched charger of any type; i.e., a
12 volt charger on a 24 volt pack or a 24 volt charger
on a 12 volt pack. An undersized charger will never
get the job done, no matter how long it tries. An over-
sized charger will cause excess gassing and heat
that could possibly result in a battery meltdown and/
or explosion.
14. Never charge a lead-acid battery with a sealed (gel
cell) battery charger. The lead-acid battery needs
higher voltage to finish its charge. Without it the bat-
tery will never come back to 100% and sulfation can
occur.
15. Always allow batteries to cool off after charging. The
cooling time is very important because heat is gen-
erated during the recharge and discharge cycles.
Without the cooling time the heat grows, accelerat-
ing grid corrosion which is one of the major causes
of battery failure. Charging practice should enable
batteries to cool before use.
16. Deep cycle batteries need to be equalized periodi-
cally. Equalizing is an extended, low current charge
performed after the normal charge cycle. It helps keep
cells in balance. Actively used batteries should be
equalized once per week. Manually timed chargers
should have the charge time extended approximately
3 hours. Automatically controlled chargers should be
unplugged and reconnected after completing a charge
cycle.
17. In situations where multiple batteries are connected
in series, parallel, or series-parallel, a replacement
battery's should be of the same size, age, and us-
age level as the companion batteries. Do not put a
new battery in a pack that has 50 or more cycles.
Either replace all the batteries with new batteries or
install a good used battery's in place of the bad. New
batteries should be given a full charge before use.
18. Periodic battery testing is an important preventative
maintenance procedure. Hydrometer readings of each
cell (fully charged) give and indication of balance and
true charge level. Imbalance could mean the need for
equalizing and is often a sign of improper charging or
a bad cell. Voltage checks (open circuit, charged
and discharged) can locate a bad cell or weak bat-
tery. Load testing will pick out a bad cell when other
methods fail. The point is to look for the abnormal. A
weak cell or battery will cause premature failure of
companion cells or batteries respectively.
19. As batteries age, their maintenance requirements
change, Generally their specific gravity is higher and
gassing voltage goes up. This means longer charg-
ing time and/or higher finish rate (higher amperage at
the end of charge). Usually, older batteries need to
be watered more often and their capacity decreases.
20. “Opportunity charging”, a short partial charge during
an extended duty cycle, is a controversial subject.
Generally, the practice is a “crutch” to make up for
undersized batteries. The correct approach is to in-
stall adequate battery capacity. If this is impossible
because of lack of space in the battery compartment
or extreme operating conditions (24 hour intermittent
use, as an example), “opportunity charging” is better
than excessive battery discharging. However, the
practice can cause batteries to over heat, require
more watering, and usually will shorten battery life.
“Opportunity charging” is a trade off; something to
avoid if possible. One charging cycle per day is pref-
erable.
21. Extreme temperatures can substantially affect bat-
tery performance and charging. Cold reduces bat-
tery capacity and retards charging. Heat increases
water usage and can result in overcharging. Very high
temperature can cause “thermal run away” which may
lead to and explosion or fire. If extreme temperature
is an unavoidable part of an application, consult a
battery/charger specialist about ways to deal with
the problem.
22. An overly discharged battery might need to be cycled
a few times before it can recover fully. If a battery
begins to heat before coming up to a full charge, it
might be necessary to discharge the battery and re-
charge it a few times. The charge and discharge cycle
might help the current acceptance of the battery and
facilitate its recovery to a usable condition.
23. Inactivity can be harmful to deep cycle batteries. If
they sit for several months, a “boost” charge should
be given – more frequently in warm climate (about
once a month) than in cold (every 2-3 months).
24. Never store a battery in a discharged state. The sul-
fate that forms during discharge can make the bat-
tery impossible to recharge fully.
Battery Charger
The aerial platform is equipped with an onboard auto-
matic battery charger. This charger has an electronic cir-
cuit that will completely recharge the batteries and auto-
matically turn off after the charge cycle is completed.
The charging cycle may last 1 1/2 to 18 hours depending
on the state of charge of the batteries. If the charging
cycle should exceed 18 hours without the batteries be-