Service Manual

Groundsmaster 7200/7210Page 5 - 34Electrical System
B. Temperature correct each cell reading. For each
10
o
F(5.5
o
C) above 80
o
F(26.7
o
C) add 0.004 to the
specific gravity reading. For each 10
o
F(5.5
o
C) be-
low 80
o
F(26.7
o
C) subtract 0.004 from the specific
gravity reading.
Example: Cell Temperature 100
o
F
Cell Gravity 1.245
100
o
F minus 80
o
F equals 20
o
F
(37.7
o
C minus 26.7
o
C equals 11.0
o
C)
20
o
F multiply by 0.004/10
o
F equals 0.008
(11
o
C multiply by 0.004/5.5
o
C equals 0.008)
ADD (conversion above) 0.008
Correction to 80
o
F(26.7
o
C) 1.253
C. If the difference between the highest and lowest
cell specific gravity is 0.050 or greater or the lowest
cell specific gravity is less than 1.225, charge the bat-
tery. Charge at the recommended rate and time giv-
en in Charging or until all cells specific gravity is
1.225 or greater with the difference in specific gravity
between the highest and lowest cell less than 0.050.
If these charging conditions can not be met, replace
the battery.
3. Perform a high- discharge test with an adjustable
load tester.
This is one of the most reliable means of testing a b attery
as it simulates the cold- cranking test. A commercial bat-
tery load tester is required to perform this test.
CAUTION
Follow the manufacturer’s instructions when us-
ing a battery tester.
A. Check the voltage across the battery terminals
prior to testing the battery. If the voltage is less than
12.4 VDC, charge the battery before proceeding with
test.
B. If the battery has been charged, apply a 150 amp
load for 15 seconds to remove the surface charge.
Use a battery load tester f ollowing the manufactur-
er’s instructions.
C. Make sure battery terminals are free of corrosion.
D. Measure the electrolyte temperature of the cen-
ter cell.
E. Connect a battery load tester to the battery termi-
nals following the manufacturer ’s instructions.
Connect a digital multimeter to the battery terminals.
F. Apply a test load of one half the Cranking Perfor-
mance (see Battery Specifications) rating of the bat-
tery for 15 seconds.
G. Take the test voltage reading at 1 5 seconds, then
remove the load.
H. Using the table below, determine the minimum
voltage for the center cell electrolyte temperature
reading.
Minimum
Voltage
Battery Electrolyte
Temperature
9.6 70
o
F(andup) 21.1
o
C(andup)
9.5 60
o
F 15.6
o
C
9.4 50
o
F 10.0
o
C
9.3 40
o
F 4.4
o
C
9.1 30
o
F -1.1
o
C
8.9 20
o
F -6.7
o
C
8.7 10
o
F -12.2
o
C
8.5 0
o
F -17.8
o
C
I. If the test voltage is below the minimum, replace
the battery. If the test voltage is at or above the mini-
mum, return the battery to service.
Installation (Fig. 46)
IMPORTANT: To prevent possible electrical prob-
lems, install only a fully charged battery.
1. Make sure ignition and all accessories are OFF.
2. Make sure battery compartment is clean and re-
painted if necessary. Place battery tray in position.
3. Make sure all battery cables, battery retainer and
electrical connections are in good condition.
4. Place battery in its compartment. Make sure battery
is level and flat. Connect positive (+) cable connector
onto positive (+) battery post. Secure cable cap screw
and lock nut using two wrenches.
5. Secure battery retainer with flat washer and flange
nut. Do not overtighten to prevent cracking or distorting
the battery case.
6. Connect a digital multimeter ( set to amps) between
the negative (- ) battery post and the negative (- ) cable
connector. The reading should be less than 0.1 amp. A
reading of more than 0.1 amp usually indicates a faulty
switch, a shorted circuit or grounded wire. Identify and
repair electrical faults before returning machine to ser-
vice.