2200 SRM 1357
Electrical System Checks
Electrical System Checks
WARNING
Disconnect the battery before opening the com-
partment cover or inspecting or repairing the
electrical system. If a tool causes a short cir-
cuit, the high current flow from the battery can
cause personal injury or property damage.
The capacitor in the controller can hold an
electrical charge after the battery is discon-
nected. To prevent electrical shock, disconnect
the battery and discharge the capacitor before
inspecting or repairing any component in the
drive unit compartment. Always wear safety
glasses.
CAUTION
The correct meter polarity is necessary for the
checks. The voltage checks are made between
the point indicated and battery negative. Con-
nect the meter negative to battery negative.
Always disconnect the battery and discharge
the capacitor before disconnecting cables
from the controller. Never put power to the
controller with any cables or wires discon-
nected. Never short any controller or motor
terminal to the battery. Always follow proper
procedure when working in the electrical sys-
tem.
1.
Turn the key switch to the OFF position.
2.
Disconnect and separate the battery connectors.
NOTE:
The battery does not have to be removed to
check the specific gravity.
3.
Check the specific gravity of the battery. If the
specific gravity is less than 1.260, the battery is
not fully charged or is damaged. A fully charged
battery has a specific gravity of 1.270 to 1.290.
A discharged battery has a specific gravity of ap-
proximately 1.165 or less. Refer to Industrial
Battery 2240 SRM 1.
4.
Remove the drive unit compartment covers. See
Periodic Maintenance 8000 SRM 1368.
5.
Discharge the capacitor. See Special Precautions
in this section.
6.
The electric lift truck has a two-wire system. The
frame must not be a common electrical path. Us-
ing an ohmmeter, check for 50,000 ohms or more
between each terminal of the battery connector
(truck end) and a clean connection on the frame.
Remove any electrical paths between the con-
troller and the frame of the lift truck, such as
a dirty battery case. Carbon dust in a motor or
other parts can cause an electrical path. Check
for additional equipment that may provide an
electrical path to the frame.
7.
Check for voltage between each terminal of the
battery connector (battery end) and a clean con-
nection on the frame. Normally there is small
voltage (less than 30% of the battery voltage) be-
tween the battery and the frame, even though the
resistance is very high. A higher voltage can in-
dicate a dirty or damaged battery. Clean battery
and battery compartment as necessary.
8.
Visually check for parts or wires that are loose or
damaged.
WARNING
Some checks require the battery to be recon-
nected. Do not connect the battery until the
point of the procedure when you are directed
to do so. Raise the drive wheel of the truck and
position on solid hardwood blocks to prevent
unexpected movement when working with the
battery connected.
9.
Always follow proper procedure when working in
the electrical system..See Table 1.
NOTE:
Make an identification of any wires before you
disconnect them. The wires must be connected cor-
rectly after checks or repairs.
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