vious versions at the Internet Archive. Yahoo! is not affiliated with the authors of this page or responsible for its content.
Commercial Products ELECTRICAL SYSTEM POCKET GUIDE Starting System Test
This is an excellent test to use when a slow crank/no start
problem is encountered. It will tell you if the problem is due to
an electrical open, short or high resistance in the starter
circuit.
NOTE: The battery condition and the state of charge must be
checked before testing the starter system.
Tool(s) required: Digital Multimeter and Inductive
Ammeter (AC/DC Current Transducer).
Test instructions: Properly connect the inductive Ammeter to
the multimeter ( refer to the manufacturers instructions). Set
multimeter on Volts scale. With the key off place the inductive
ammeter around the main negative (-) battery cable and read
the meter prior to activating the starter system. Adjust the
meter to read zero ( if applicable). Crank the engine for at
least 3 seconds and record the results.
Typical Starter System Draw
at 65
°
°
F (18
°
°
C)
Groundsmaster 223-D
215A
Groundsmaster 224
110A
Groundsmaster 325-D
210A
Groundsmaster 345
75A
Groundsmaster 455-D
230A
Greensmaster 3000 85A
Reelmaster 223-D/5100-D 215A
Reelmaster 5300-D 250A
Reelmaster 335-D/3500-D 230A
Reelmaster 450-D/4500-D 300A
Workman 3200 90A
Workman 3200-D 170A
Sand Pro 5000 125A
Multi-Pro 1100 80A
Hydroject 3000 110A
Battery Test
Use a Digital multimeter to measure the voltage between
the battery terminals.
Set the multimeter to the DC volt setting. The battery
should be at a temperature of 60
°
to 100
°
F (19
°
to
38
°
C). The ignition key should be off and all acces-
sories turned off. Connect the positive (+) multimeter
lead to the positive battery post and the negative (-)
multimeter lead to the negative battery post.
NOTE: this test provided a relative condition of the
battery. Load testing of the battery will provide more
accurate information.
Voltage Measured Battery Charge
12.6 V (or higher) Fully charged (100%)
12.4 V 75% charged
12.2 V 50% charged
12.0V 25% charged
Voltage Drop Testing
This is a simple test that should be used to locate
excess resistance in an electrical circuit.
Tool required: Digital Multimeter
DC volts setting.
Test instructions: Connect the positive (+) test lead
to the power (or most positive) side of the compo-
nent, circuit or connection. Connect the negative (-)
test lead to the ground (of least positive) side of the
component, circuit of connection. Turn on the circuit
to be tested and read the voltage. Remember - when
performing voltage drop tests the circuit must be
complete and activated to locate the resistance.
Voltage Drop Specifications ( Maxi-
mums
)
High Amperage
Circuits (>20A)
Low Amperage
Circuits (<20A)
0.4 Volt feed side 0.2 Volt feed side
0.4 Volt ground
side
0.2 Volt ground side
Commercial Products
ELECTRICAL SYSTEM
POCKET GUIDE
©
The Toro Company -1996
Part No. 96887SL Specific Gravity Test
The state of the battery charge is indicated by the specific gravity or weight of the battery electrolyte. Specific
gravity can be measured very quickly by means of a battery hydrometer with a thermometer for temperature
correction. Hydrometers are calibrated to measure specific gravity correctly at an electrolyte temperature of
80
°
F. To determine the correct specific gravity reading when the temperature of the electrolyte is other than
80
°
F:
Add to the hydrometer reading four gravity points (0.004) for each 10
°
F
above 80
°
F.
Subtract four
gravity points (0.004) for each 10
°
F
Below 80
°
F.
Battery Testing Chart
TEST
TEST RESULTS
CONDITION
CORRECTIVE
PROCEDURE
SPECIFIC
GRAVITY
TEST
@ 80
°
°
F
GRAVITY BETWEEN
1.250 - 1.280
CHARGED
PERFORM LOAD
TEST
GRAVITY BELOW
1.240
DISCHARGED
RECHARGE
PERFORM LOAD
TEST
MORE THAN 50 GRAVITY
POINTS (0.050)
VARIATION BETWEEN
CELLS
(A) SHORTED CELL
(B) ACID LOST
(C) OLD BATTERY
REPLACE
Charging System Test
This is a simple test used to determine if a charging system is functioning. It will tell you if the
charging system has output, but not how much (amps) or what it is capable of.
Tool required: Digital multimeter - DC volts setting
Test instructions: Connect the positive (+) multimeter lead to the positive battery post , and the
negative (-) test lead to the negative battery post. Note the battery voltage.(Open Circuit Test)
Leave the test leads connected and start the engine and run at 2200 RPM minimum. Test
results should be:
At least 1 volt over Open Circuit test results
Open Circuit Test results
= 12.5 V
Charging System Test results
= 13.5 V
Difference
= +1.0 V
Battery Load Test
To test a batteries ability to deliver current under a load, use a battery load test. This test is
made using a battery load tester. To test the battery connect the load tester to the battery posts
and apply a current load of one-half the cold cranking amperage for 15 seconds. If the cold
cranking amperage is not known, use three times the Amp-Hr rating of the battery for 12 volt
batteries ( two times the Amp-Hr rating for 6 volt batteries). Check the minimum terminal voltage
and reference the temperature compensation chart. If the battery fails this test recharge the
battery and test again.
Temperature Compensation Chart
Battery electrolyte
temperature
Minimum voltage
under load @ end of test
70
°
F (21 deg C)
60
°
F (16 deg C)
50
°
F (10 deg C)
40
°
F (4 deg C)
30
°
F (-1 deg C)
20
°
F (-7 deg C)
10
°
F (-12 deg C)
0
°
F (-18 deg C)
9.6 VOLTS
9.5 VOLTS
9.4 VOLTS
9.3 VOLTS
9.1 VOLTS
8.9 VOLTS
8.7 VOLTS
8.5 VOLTS
Schematic Symbols