Perkins 854E-E34TA Systems Operation Testing And Adjusting page 82

82
Electrical System
d. Turn the disconnect switch to the ON position.
Connect an ammeter across the disconnect
switch terminals. Connect the red lead to the
terminal on the frame side. Connect the black
lead to the terminal on the battery. If a
multimeter is used for the test use the ten amp
connections to avoid damage.
e. Turn the disconnect switch to the OFF
position. Record the value of the electrical
current.
f. The current is below 0.05 amperes. The
charging system is currently good. The fault is
possibly an intermittent draw in the system.
The batteries may be faulty. Check that no
accessories were on during the test.
Note: The standard acceptable draw is 0.05
amperes. A current that is greater than this value
usually indicates a problem. However, some large
machines with multiple control modules have a
higher acceptable limit.
g. The current value is above 0.05 amperes.
There is a current draw in the system. Go to
step 7.
5. Turn off all accessories. Turn the keyswitch to the
OFF position.
a. Connect a current probe or an ammeter to a
digital multimeter. Ensure that the probe is
zeroed. Clamp the current probe or an
ammeter around the ground cable. Clamp the
tool with the positive side away from the
battery. Record the value of the electrical
current.
b. The current value is below 2 amperes. Go to
step 4.d..
c. The current value is above 2 amperes. Go to
step 7.
d. Remove the ground cable from the battery
terminal. For systems with four batteries or 12
V systems with two batteries, disconnect the
ground cables from both negative batteries.
e. Connect an ammeter between the
disconnected battery ground cable and one of
the negative battery terminals. Connect the red
lead to the cable. Connect the black lead to the
terminal on the battery. If a multimeter is used
for the test use the ten amp connections to
avoid damage.
This document is printed from SPI². Not for RESALE
f. The current is below 0.05 amperes. The
charging system is currently good. The fault is
possibly an intermittent draw in the system.
The batteries may be faulty. Check that no
accessories were on during the test.
Note: The standard acceptable draw is 0.05
amperes. A current value above this figure usually
indicates a problem. However, some large
machines with multiple control modules have a
higher acceptable limit.
g. The current value is above 0.05 amperes.
There is a current draw in the system. Go to
step 7.
6. Check the condition of the poly v-belt and
alternator pulley.
a. If the poly v-belt is oily, clean the pulleys.
Replace the poly v-belt. Refer to Disassembly
and Assembly, "Alternator Belt - Remove and
Install" for the correct procedure. Inspect the
poly v-belt for wear or for cracks. Refer to
Systems Operation, Testing and Adjusting, "V-
Belt - Test". If the poly v-belt is wet, dry the
poly v-belt and the pulleys. Retest the system.
b. Inspect the nut on the alternator pulley. Ensure
that the nut is not loose. If the nut is loose,
tighten the nut to the correct torque. Refer to
Specifications, "Alternator" for the correct
torque.
c. If no faults are found from the procedures in
step 6.a. and step 6.b., inspect the charging
system. Refer to Systems Operation, Testing
and Adjusting, "Charging System - Test" for the
correct procedure.
7. Turn the keyswitch to the OFF position.
a. Connect a current probe or an ammeter to a
digital multimeter. Ensure that the probe is
zeroed. Clamp the current probe or an
ammeter around the "B+" cable. Clamp the
tool with the positive side away from the
battery. Record the value of the electrical
current.
b. The current is less than two amperes. Go to
step 7.d..
c. The current is more than two amperes. There
is an internal problem with the alternator.
Replace the alternator. Refer to Disassembly
and Assembly, "Alternator - Remove and
Install" for the correct procedure.
UENR0623