ELECTRICAL AR 1402241 - Caterpillar

2-1 Structural Diagram
2-2 Function
(1) General Electric circuits for this model are DC24V minus grounding consisting of starting circuit, charging circuit and low current circuit.The starting circuit is to start the engine.The charging circuit operates while engine is running which charges the battery and also supplies current to the low current circuit.The low current circuit receives current from the battery or charging circuit and operates all electrical units. (2) Functions 1. Starting circuit Consists of battery (33), battery relay (30), starter (31), magnetic switch (29), starting switch (5) and circuit breaker (8), and starts the engine.2. Charging circuit With alternator (32) mounted on the engine, charging circuit charges battery (33) and also feeds current to the low current circuit through fuse box (20).3. Low current circuit 1) Light (head and boom) circuit Turns lights (40) for head and boom on.2) Fuel meter circuit and water temperature meter circuit Indicate the volume of fuel remaining in the fuel tank and temperature of the engine coolant.3) Hourmeter circuit Indicates the engine running hours.4) Wiper circuit and washer circuit Wipes off dirts on the front wind shield of cab.5) Horn circuit Blows the electric horn.6) Radio circuit Receives FM and AM frequency radio broadcast.7) Cigar lighter circuit Electrically heats a coil used for lighting cigarettes.8) Cab heater circuit Drives heater fan to heat inside the cab.9) Room lamp and engine hood lamp circuit Lights up the cab room lamp and engine hood lamp.10) Seat belt lamp circuit Lights up the seat belt lamp for approximately 30 seconds after engine has started to warn the operator to fasten the seat belt.11) Travel alarm circuit Sounds the alarm anytime that the forward or reverse travel lever is moved.12) Travel equalizing circuit Offers a straight travel in a combined operation of travel and any other operation.13) Swing brake circuit Applies brake to the upperstructure.14) Auto-decel. circuit Automatically detects that all the actuators are in neutral and lowers the engine speed to low idling.15) Ether start circuit Injects ether into the engine intake system to help engine start.2-3 Operation
(1) Start circuit (2) Charging circuit (3) Low current circuit 1. Light (head and boom) circuit 2. Fuel meter circuit, water temperature meter circuit * Fuel meter circuit * The same theory as above applies to water temperature meter circuit.3. Hourmeter circuit 4. Wiper circuit and washer circuit (Option) * Wiper circuit * Washer circuitPushing washer switch (35) forward allows current flow to window washer (39), which operates the window washer.5. Horn circuit 6. Radio circuit Turning power switch on the face of tuner (13) feeds current from fuse box (20) and converter (14) which operates the tuner (13) electric circuit, then radio frequency fetched from antenna is output from the speaker (15) as sound.7. Cigar lighter circuit 8. Cab heater circuit 9. Room lamp and engine hood lamp circuit Moving the switch of lamp (37) to the right allows current flow from fuse box (20) to body ground through lamp (37), which lights up lamp