DRESSTA TD-25M EXTRA, Service Manual

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ELECTRICAL
SECTION 8
Page 1
DRESSTA TD-25M EXTRA
SERVICE /SPECIAL TOOLS
1. SERVICE /SPECIAL TOOLS
DESCRIPTION TOOL NUMBER
Volt/Ammeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Locally purchased
Electronic Battery Tester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Locally purchased
GENERAL
2. DESCRIPTION
A 24 [V] negatively grounded electrical system is used, consisting of a tractor circuit and cab
circuit.
Four 12 [V] batteries connected in series - parallel supply the 24 [V].
A master switch located on the positive side of the electrical circuit, is used to cut out the electrical
power.
The lights are sealed type and are controlled by the light switches on the cab panel.
The circuits are protected by automatic reset circuit breakers. In the event of a short circuit or
ground, the circuit breaker will open before damage occurs and will continue to open and close
until the trouble clears or is corrected. The circuit breaker will then return and stay in its normal
closed position. As a guide for identifying the various electrical units and for tracing the electrical
cables and connections, refer to the WIRING DIAGRAMS in this SECTION.
IMPORTANT: Never disconnect the alternator, master switch or batteries while the alternator
is in operation.
Surfaces under all terminals must be clean, and good electrical connections must be established
after assembly. All clips must grip cables tightly to prevent vibration and rapid cable wear.
CAUTION! When installing batteries, be sure to connect the ground cable to the
negative (-) terminal.
Before working on any part of the electrical system turn the master switch
in the "OFF" position and take key out from both the master switch and starting
switch to prevent accidental starting.
WIRING DIAGRAM
3. ELECTRICAL SYSTEM (Fig. 8.1)
Electrical tractor system consists of starting circuit, charging circuit, fan circuit, drive train control
circuit, equipment circuit, warning lamps circuit and accessories circuit.
a. Starting Circuit
The electric system master switch (71) located in the positive lead of batteries (64) must be in the
“ON” position to complete the battery circuit for starting power. When the starting key is turned in
the starting switch (39) to “START”, current flows from battery to starting switch (39) and by one of
circuit breaker (40) 10 [A] to start-up lock switch (13). If the drive train lock lever is in “ON” (locked)
position, current flows by start-up lock switch (13) closed contacts to solenoid of starting magnetic
switch (60).