Calculating Charge Time - Schumacher Electric FARM & RANCH FR01238 Manual Del Usuario

NOTE: If you have charged the battery
and it still will not start your car, do not
use the Engine Start feature, or it could
damage the vehicle's electrical system.
Have the battery checked.
1. Set the volt/amp selector switc to the
OFF position.
2. With the charger unplugged from the
AC outlet, connect the charger to the
battery, following the instructions given
in the CHARGING A BATTERY IN
THE VEHICLE section.
3. Plug the charger's AC power cord into
the AC outlet.
4. With the charger plugged in and
connected to the battery of the
vehicle, set the volt/amp selector
switch to the engine start position.
5. Crank the engine until it starts or 5
seconds pass. If the engine does not
start, wait 3 minutes before cranking
again. This allows the charger and
battery to cool down.

12. CALCULATING CHARGE TIME

When you know the percent of charge and
the Amp hour (Ah) rating of your battery,
you can calculate the approximate time
needed to bring your battery to a full charge.
Example:
Amp hour rating = Reserve capacity + 16
NOTE: The Reserve Capacity can be
obtained from the battery's specification
sheet or the owners manual.
To calculate the time needed for a charge:
1. Find the percentage of charge needed.
2. Multiply the Amp hour rating by the
charge needed, and divide by the
charge rate.
3. Multiply the results by 1.25 to find the
total time needed, in hours, to bring
the battery to full charge.
4. Add an additional hour for a deep-cycle
battery.
BATTERY CHARGING TIMES
CARS/TRUCKS
MARINE/DEEP CYCLE
2
BATTERY SIZE/RATING
200-315 CCA
315-550 CCA
550-875 CCA
NOTE: During extremely cold weather,
or if the battery is under 2 volts, charge
the battery for 5 minutes before cranking
the engine.
6. If the engine fails to start, charge the
battery for 5 more minutes before
attempting to crank the engine again.
7. After the engine starts, move the
volt/amp selector switch to the OFF
position and unplug the AC power
cord before disconnecting the battery
clamps from the vehicle.
8. Clean and store the charger in a dry
location.
NOTE: If the engine does turn over but
never starts, there is not a problem with
the starting system; there is a problem
somewhere else with the vehicle.
STOP cranking the engine until the
other problem has been diagnosed and
corrected.
Example:
Ah rating x % of charge needed x 1.25 = hrs of charge
Charger Amp setting
100 (Ah rating) x .50 (charge needed) x 1.25 = 3.125 hrs
20 (Charger Setting)
100 x .50 x 1.25 = 3.125
20
You need to charge a 100 Ampere hour
battery for a little more than 3 hrs at a 20
Amp charge rate, using this example.
Use the following table to determine the
time it will take to bring a battery to full
charge.
The times given are for batteries with a
50% charge prior to recharging.
CCA – Cold Cranking Amps
RC – Reserve Capacity
MC Marine Capacity
NR – NOT RECOMMENDED
40-60 RC 2¼-4 hours
60-85 RC 4-7 hours
85-125 RC 7-11 hours
55 MC
80 MC 10 hours
105 MC 13 hours
• 6 •
CHARGE RATE /
CHARGING TIME
10A 30A
½-1 hour
1-2 hours
2-7 hours
7 hours NR
NR
NR