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| Illustration 1 | g01383464 |
Left Side of Machine (1) Generator power panel (2) Tool enable switch | |
Generator power panel (1) is located on the left side of the machine. The panel provides electrical outlets at 120 volt and 240 volt supply voltage for the use of electrical lighting and tools. Electrical outlet frequency is determined by engine speed for belt driven generators. Electrical outlet frequency is constant for hydraulic generators. Each electrical outlet is protected by an associated circuit breaker.
Machines with a belt driven generator are equipped with tool enable switch (2). The tool enable switch is a toggle switch with two positions. The bottom position is the OFF position. The top position is the ON position. When this switch is in the ON position, the machine ECM reads a ground signal at terminal "J1-63". When the tool enable switch is in the ON position, the machine ECM prompts the engine ECM to maintain the engine speed at 1250 rpm. This engine speed maintains an electrical outlet frequency of 62.5 ± 1.0 Hz. The tool enable switch allows an operator at ground level to prevent the engine, which controls generator frequency, from operating at any speed higher than 1250 rpm.
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| Illustration 2 | g01383468 |
Left Side of Machine (3) Generator | |
Generator (3) is located on the left side of the machine. The left access door provides access to the generator.
Generator (3) produces electrical power for the use of lighting or tools during machine operation. The generator may be driven by a hydraulic motor. Also, the generator may be belt driven by the engine.
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| Illustration 3 | g01383474 |
Rear of Generator (4) Right screed extension heating element (GFCI circuit breaker) (5) Right main screed heating element (GFCI circuit breaker) (6) Left main screed heating element (GFCI circuit breaker) (7) Left screed extension heating element (GFCI circuit breaker) (8) Main circuit breaker for auxiliary power panel (no GFCI) | |
The generator circuit breaker panel is located on the rear of the generator set. The panel is under a hinged access panel. The panel contains the following circuit breakers:
- Circuit breaker (4) for the heating element on the right screed extension
- Circuit breaker (5) for the heating element on the right main screed plate
- Circuit breaker (6) for the heating element on the left main screed plate
- Circuit breaker (7) for the heating element on the left screed extension
- Main circuit breaker (8)
Main circuit breaker (3) protects generator power panel. The following circuit breakers are ground fault protected devices: circuit breaker (8), circuit breaker (4), circuit breaker (5) and circuit breaker (6). These circuit breakers are used when the machine is equipped with an electric screed heater.
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| Illustration 4 | g01383485 |
Front of Generator (9) Hydraulic generator relay | |
Hydraulic generator relay (9) is located on the left side of the machine. The relay is in front of the generator. The coil of the relay receives power from the auxiliary circuit breaker. Terminal "J2-9" of the machine ECM provides a ground signal to the relay coil when the generator control switch is in the ON position.
When the coil of hydraulic generator relay (9) is energized, power is transferred from the auxiliary circuit breaker to the generator hydraulic solenoid. When the hydraulic solenoid is energized, hydraulic oil is directed from the generator pump to the generator motor.
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| Illustration 5 | g01383486 |
Rear of Generator (10) Generator relay | |
Generator relay (10) for the belt driven generator is located on the rear side of the generator. The rear panel provides access to this component.
The coil of generator relay (10) receives power from the auxiliary circuit breaker. Terminal "J2-9" of the machine ECM provides a ground signal to the relay coil when the generator control switch is in the ON position. When the coil is energized, the generator relay closes. This action connects terminal "E+" on the generator terminal board to terminal "E+" on the generator circuit board. When the relay is energized, excitation current is provided to the generator armature, and the generator provides voltage to the generator panel.
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| Illustration 6 | g01383488 |
Compartment at Front of Operator Station (11) Machine ECM (12) Connector "J2 " (13) Connector "J1" | |
Machine ECM (11) is mounted to the door of the compartment at the front of the operator station. The compartment door provides access to this component.
Machine ECM (11) controls the generator system. This ECM has two 70-pin connectors, connector "J1" (13) and connector "J2" (12) .
Machine ECM (11) communicates with the left operator control unit and the machine ECM through the Cat Data Link and the controller area network (CAN). The Cat Data Link is a proprietary communication standard that was developed by Caterpillar Inc. The Cat Data Link requires a positive line and a negative line. The positive line is connected to terminal "J1-10" of the machine ECM. The negative line is connected to terminal "J1-20" of the machine ECM.
The CAN lines provide high speed communication between machine ECM (11) and the engine ECM. The CAN requires a positive line and a negative line. The machine ECM contains two positive CAN lines and two negative CAN lines. The positive lines are connected to terminal "J2-56" and to terminal "J2-67" of the machine ECM. The negative lines are connected to terminal "J2-68" and to terminal "J2-70" of the machine ECM.
The machine ECM analyzes input signals. The machine ECM determines if a ground signal should be sent to the hydraulic generator relay (hydraulic generators) or if a ground signal should be sent to the generator relay (belt driven generators). Machine ECM (11) provides a ground path for the hydraulic generator relay or for the generator relay at terminal "J2-9.".
When the generator control switch is in the ON position, the machine ECM sends an engine speed signal to the engine ECM through the CAN. This signal prompts the engine ECM to prevent the engine speed from decreasing below 1250 rpm.
When tool enable switch (2) is in the ON position, the machine ECM sends an engine speed request to the engine ECM through the CAT Data Link. This signal causes the engine ECM to operate the engine at 1250 rpm.
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| Illustration 7 | g01383493 |
View of Machine Under the Operator Seat (14) Left operator control unit (15) Connector "J1" (16) Connector "J2" | |
Left operator control unit (14) is located under the left operator seat. This control unit has two 70-pin connectors. Connector "J1" (15) is the front connector and connector "J2" (16) is the rear connector.
Left operator control unit (14) monitors input devices which are located in the left operator station. The control unit communicates with machine ECM (12) through the Cat Data Link and the CAN lines.
Left operator control unit (14) monitors input signals at terminal "J2-29" in order to determine the position of the generator control switch. When the circuit at terminal "J2-29" is grounded, the control unit determines that the generator control switch is in the ON position.
This signal is transferred to machine ECM (11) through the CAT Data Link and the CAN lines.
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| Illustration 8 | g01383496 |
Compartment at Front of Operator Station (17) Operator ECM circuit breaker (18) Machine ECM circuit breaker (19) Auxiliary circuit breaker | |
A circuit breaker panel is mounted to the door of the compartment at the front of the operator station. The compartment door provides access to these components. The circuit breaker panel contains the following circuit breakers which are part of the generator system:
- Operator ECM circuit breaker (17)
- Machine ECM circuit breaker (18)
- Auxiliary circuit breaker (19)
When the electrical disconnect switch is in the ON position, power from the main circuit breaker is available at operator ECM circuit breaker (17) and at machine ECM circuit breaker (18). When the main power relay is energized, power from the main circuit breaker is available at auxiliary circuit breaker (19).
Operator ECM circuit breaker (17) is a manual reset breaker. This circuit breaker is rated at 20 amp. Power transfers from this circuit breaker to the following terminals of the left operator control unit: terminal "J1-31", terminal "J1-39" and terminal "J1-47".
Machine ECM circuit breaker (18) is a manual reset breaker. This circuit breaker is rated at 20 amp. Power transfers from this circuit breaker to the following terminals of the machine ECM: terminal "J1-31", terminal "J1-39" and terminal "J1-47".
Auxiliary circuit breaker (19) is a manual reset breaker. This circuit breaker is rated at 15 amp. Power transfers from this circuit breaker to the coil of the hydraulic generator relay (hydraulic generators). Also, power transfers to the coil of the generator relay (belt driven generators). On machines that are equipped with the hydraulic generator, power also transfers from this circuit breaker to contact "87" of the hydraulic generator relay.