© 2021 Copyright Newmar Corporation. All rights reserved. For the most up-to-date version of this content, and for more product-specific information, please refer to Newgle.
51
ELECTRICAL
EXAMPLE
Most products requiring electricity provide how many
amps or watts it typically utilizes. If your electric hot water
heater is always in use (~12.5 amps), and you start your air
conditioner (~15.0 Amps) and put on a pot of coffee (~9.0
amps) and make some toast (~8.0 amps) while watching
TV (~ 2.0 amps), you have far exceeded the 30 amp
service, resulting in a tripped breaker.
-
+
Batteries
Provides information about the house and chassis battery banks, battery inspection and care, as well as
battery replacement.
Battery Basics
Introduction
As with anything technical, greater knowledge of the
basics may help you increase performance, reliability,
and longevity, as well as prevent future problems with
your batteries. This article will provide information
regarding your coach batteries; however, this is only one
aspect of your coach’s electrical system. To learn more
about your batteries’ role within the system, please refer
to the 12 Volt Electrical article.
Commercial lead acid batteries have been used for
over 150 years. The same chemical principal used to
store energy now was also used many generations
ago. Present day chassis battery power requirements
are tremendous, considering today’s vehicles and all
of the electrical devices that must be supplied. All of
these electronics require a reliable power source, and
poor battery condition may lead to expensive electronic
component failure. A battery is like a piggy bank - it
stores energy, but cannot produce it. If you continue to
withdraw without making any deposits, you will soon
have nothing left.
Life Span of A Battery
Not long ago, motor homes only used a single 12 Volt
house battery. Today, however, it is standard to have at
least two batteries, and up to 16 total in some Newmar
coaches, powering inverters up to 3000 watts. As energy
requirements increase, the average battery life decreases.
The life span of a deep cycle battery will vary considerably
with how it is used, how it is maintained and charged,
temperature, and other factors. The life span is dependent
upon usage but often ranges between six months to 48
months. Only 30 percent of all batteries actually reach the
48 month mark.
It is best practice to change the complete battery bank
when a new battery becomes necessary, as the battery
bank is only as good as the weakest cell. One simple way
to extend battery life is to hook it up to a solar charger
during the off months.
Many people don’t take into consideration how much
power may be used by the inverters charging circuits
mostly because they are working automatically in the
background. 50 amp service has two 50 amp power legs,
providing a total service of 100 amps.
Common Battery Terms
Ampere (Amp)
- A unit that defines the flow rate of
electricity (current) in a circuit.
Amp Hour (AH)
- Measurement of electrical storage
capacity on a deep cycle battery. The standard amp rating
is taken for 20 hours. Example: A 100 AH rated battery is
determined like this: Draw from the battery for 20 hours
provides a total of 100 amp hours, translating to about five
amps an hour (5 amps x 20 hours = 100 AH). However, it is
important to know that the total time of discharge and load
applied is not a linear relationship. As your load increases,
your realized capacity decreases. This means if you
discharged that same 100 AH battery by a 100 amp load, it
will not give you one hour of runtime. On the contrary, the
perceived capacity of the battery will be about 64 AH.
Cold Cranking Amps (CCA)
-Measures the number
of amps a battery can deliver at 0° F for 30 seconds
without dropping below 7.2 Volts (1.2 Volts per cell). A
high CCA battery rating is especially important in engine-
starting battery applications and in cold weather. This
measurement is not particularly important in deep cycle
batteries, though it is the most commonly known battery
measurement.
Cranking Amps (CA)
- Measures available current at 32° F
and is also called marine cranking amps (MCA).
Depth of Discharge (DOD)
- Measures the percent of
rated capacity to which a cell or battery is discharged. It
is the reciprocal of a battery’s state of charge. Example: A
battery that has a depth of discharge of 45 percent has a
state of charge of 55 percent.
Reserve Capacity (RC)
- Measures the number of minutes
a fully charged battery can continuously deliver 25 amps
at 80 ° F before the voltage drops below 10.5 Volts. This
measurement represents the amount of time the battery
can operate if a charging system failure occurs.
Electrolyte Specific Gravity (battery test)
- Unit of
measure which compares the weight of the electrolyte
solution to the weight of water. This test is performed
with a hydometer or a refractometer that is made for
testing batteries. This type of test is used to determine
the battery’s state of charge; however, it cannot be used
on sealed batteries.
Summary of Contents for Kountry Star 2022
Page 1: ...SM 2022...
