User Manual

10
Rated
Capacity
The Yuasa Battery Specifi cations & Applications guide lists
information including: Battery Type, Dimensions and Capacity in
Amp Hours (AH).
vs. mowing the lawn) all affect battery choice and
how well a battery will perform over its lifetime.
Battery Ratings
Because a battery’s basic job is to power the starter
motor while maintaining suffi cient voltage to also
run the ignition and fuel systems, there has to
be a way to rate its ability to perform these jobs.
Powersports batteries are rated in ampere-hours
(AH) and/or cold cranking amps (CCA). A battery’s
ability to discharge a given amount of current
over a specifi c length of time is the AH rating.
The AH rating is based on a fully charged battery
with an open circuit voltage of
13.0 that is
considered fully discharged when the voltage
reaches
10.5 volts at 77° F (25° C). The Amp Hour
ratings are printed on the battery case in two ways:
10 hour and 20 hour ratings. The following is an
example of the
10-hour rating designation for a
battery that has an
18 AH rating.
Printed on the front of the battery case is
18 Ah
(
10 HR) . This means that the battery can be discharged at a rate
of
1.8 amps for 10 hours (18/10 = 1.8) before it becomes fully
discharged.
The larger the battery plate area, the greater the ampere-hour
rating. Temperature also has an effect on AH because low
temperatures slow down the chemical reaction inside a battery.
A battery will have a lower AH capacity in cold temperatures
than in warm ones.
CCA rates how well a battery can be expected to produce
current at low temperatures. Just like AH, the CCA rating
depends on the number of plates and their total surface area.
CCA represents the discharge load in amps that a new, fully-
charged battery at
0° F can continuously deliver for 30 seconds
while maintaining
7. 2 volts. In general, as engine size increases
so does the starter motor cranking current required to start
the engine and thus CCA battery requirements. For example, a
battery with a CCA rating of
270 will start a large displacement
engine under most conditions. A battery with a rating of
310
CCA, and used in the same application, would start the engine
more reliably especially in cold weather. Because starter motor
requirements differ by year, make and model of vehicle it’s best
to check the Yuasa Battery Specifi cations & Applications guide
to select the correct original equipment replacement battery.
If a special application demands higher cranking power, select
an appropriate upgraded battery from the Yuasa battery line.
Try to match battery features to vehicle requirements. For
example, a cold start rating is important in a snowmobile but
not on a lawn tractor—unless it’s used to plow snow.
POINTS TO REMEMBER
■ A battery converts chemical energy to electrical energy
■ Each cell has approximately 2 volts: a 12-volt battery has 6
cells; a
6-volt battery has 3 cells
■ Inside each cell are electrically charged positive and
negative lead plates, isolated from each other by separators
■ Current, or amperage is the fl ow of electricity
■ Always ventilate battery charging area
■ On Conventional batteries, always remove the red sealing
cap from the vent elbow and discard it
■ Charging produces fl ammable gasses—no smoking, sparks
or fl ames
■ Always wear safety glasses, or face shields when working
with batteries
■ Battery acid in eyes, or swallowed requires immediate
antidotes and medical care
■ Battery safety considerations are important… review them
frequently