National Luna LEGACY Fridge Manual
9
•
Voltage of a battery can be an indication of its “state-of-charge”.
•
The voltage-capacity relationship is most accurate when the
fridge is not running and the battery temperature is at 25°C.
•
By measuring the voltage, we can estimate the amount of
energy remaining in the battery.
•
Changes in temperature, battery age and general battery health
can influence this relationship and therefore result in inaccurate
capacity measurement.
•
Normal battery operation takes place between 12.0 and 12.6 volts.
•
Depending on the manufacturer’s specifications a normal car’s
alternator charges between 13.7 and 14.2 volts.
•
A battery should not be discharged below 11.8 volts as a general
rule. A “deep-discharged” battery should be recharged as soon as
possible to prevent permanent damage.
Low Voltage Battery Protection
The Electronic Control Unit will cut-out at the LOW / MEDIUM / HIGH selected setting.
Once the compressor has cut-out, it will not restart (cut-in) until the voltage rises.
The table below reflects the set points.
BATTERY
CAPACITY
BATTERY
VOLTAGE
When using the unit in a 24-volt application
do not select
battery protection
“LOW”
as this may completely drain the battery bank.
(Causing permanent damage to the batteries)
12 VOLT
24 VOLT
Battery
Protection
Cut-out
Cut-in
C
ut-out
Cut-in
LOW
9.6
10.9
MED
10.4
11.7
22.8
24.2
HIGH
11.3
12.5
24.6
26.0
Note: these values are measured at the
Electronic Compressor Driver input. It is
important to note that poor / thin wiring
and bad connections to the battery can
cause a large voltage drop. When this
occurs the F
ridge switches off and will
re-start again on a repeat cycle “hunting”.
NOTE: When connecting the fridge for the first time, it will look at the cut-in voltage.
•
If the battery protection is set on “High” the initial cut in voltage will be 12.5.
•
If the battery is not fully charged the Fridge will not start. Simply select “Low” to start.
•
When selecting “Low” the Fridge will operate within a voltage supply of 9.6-31.5Vdc.
Battery Voltage vs Capacity
