Procedure to Inspect EMCP 4.2 RS485 Remote Annunciator Interface Harness On Certain 3512 and 3516 Generator Sets{1408, 4490, 7400} Caterpillar

Electric Power Generation:

3516C GEN SET (S/N: SBK1-UP)

Engine:

3512 (S/N: YAK1-UP; YAX1-UP)

3512B (S/N: YAM1-UP; YAN1-UP; YAY1-UP; YAZ1-UP)

3512C (S/N: SBG1-UP)

3516 (S/N: YAL1-UP; YAS1-UP)

3516B (S/N: YAP1-UP; YAR1-UP; YAT1-UP; YAW1-UP)

3516C (S/N: SBJ1-UP)

Introduction

This Special Instruction is to identify the basic understanding of the inspection of the EMCP4.2 Interface Harness.

Do not perform any procedure in this Special Instruction until you have read the instruction and until you understand all of the instruction.

Important Safety Information

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs.

A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly.

Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.

Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. Ensure that any tool, procedure, work method, or operating technique you use that is not recommended by Caterpillar is safe.

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Do not operate or work on this engine or generator set unless you have read and understand the instructions and warnings in the Operation and Maintenance Manuals. Failure to follow the warnings and instructions could result in injury or death. Contact any Caterpillar dealer for replacement manuals. Proper care is your responsibility.

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Accidental engine starting can cause injury or death to personnel working on the equipment. To avoid accidental engine starting, disconnect the battery cable from the negative (−) battery terminal. Completely tape all metal surfaces of the disconnected battery cable end in order to prevent contact with other metal surfaces which could activate the engine electrical system. Place a Do Not Operate tag at the Start/Stop switch location to inform personnel that the equipment is being worked on.

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Personal injury or death can result from high voltage. When power generation equipment must be in operation to make tests and/or adjustments, high voltage and current are present. Improper test equipment can fail and present a high voltage shock hazard to its user. Make sure the testing equipment is designed for and correctly operated for high voltage and current tests being made. When servicing or repairing electric power generation equipment: Make sure the unit is off-line (disconnected from any utility and/or other generators that can provide power service), and either lock out or tag as "DO NOT OPERATE". Remove all fuses. Make sure the generator engine is stopped. Make sure all batteries are disconnected. Make sure all capacitors are discharged. Failure to do so could result in personal injury or death. Make sure residual voltage in the rotor, stator and the generator is discharged.

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Only persons with training in electrical installations must carry connections to the generator. The generator must be wired correctly. A fire or electrocution could result from wiring that is incorrect. The generator is capable of generating high voltages. Ensure that the generator is not on while the connections are being made. Follow these two steps in order to prevent accidental starting: Isolate the DC breaker. Disconnect the DC supply battery.

Isolating the Generator for Maintenance

When you service an electric power generation set or when you repair an electric power generation set, follow the procedure below:

1. Stop the engine.

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Illustration 1	g00104545

2. Attach a "DO NOT OPERATE" or similar warning tag to the engine prime mover starting circuit. Disconnect the engine starting circuit.

3. Disconnect the generator from the distribution system.

4. Lock out the circuit breaker. Attach a "DO NOT OPERATE" or a similar warning tag to the circuit breaker. Refer the electrical diagram. Verify that all points of possible reverse power flow have been locked out.

5. For the following circuity, remove the transformer's fuses:
   • Power

   • Sensing

   • Control

6. Attach a "DO NOT OPERATE" or similar warning tag to the generator excitation controls.

7. Remove the cover of the generator's terminal box.

8. Use an audio/visual proximity tester in order to verify that the generator is de-energized. This tester must be insulated for the proper voltage rating. Follow all guidelines in order to verify that the tester is operational.

9. Determine that the generator is in a de-energized condition. Add ground straps to the conductors or terminals. During the entire work period, these ground straps must remain connected to the conductors and to the terminals.

Inspection Procedure

The EMCP4.2 panel (1) can be located on main box group, side extension box, or rear extension box.

Note: Isolate the generator set before commencing any work on the unit, open generator set breaker, activate Emergency Stop, disconnect the battery cables, and either disconnect or open the control circuit breaker for the AC power supply to the battery charger. Ensure that all health and safety requirements are adhered to at all times. Also, ensure proper Lock Out-Tag Out procedures are followed at all times while work is being performed on the machine. Lock out generator operation and disconnect/lockout all power sources before commencing any work.

1. Turn the machine key switch to the OFF position and disconnect machine power with the battery disconnect switch in the OFF position.

2. Perform lockout/tagout procedure on the machine by attaching a "Do Not Operate" warning tag to the machine start switch of the controls before you perform any service.

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Illustration 2	g03202590

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Illustration 3	g03202664
(1) EMCP4.2 Panel (2) 351-8758 Generator Set Control Gp (EMCP 4.2 Control Gp) (3) 371-2226 Panel Harness As (MUI Interface Harness) / 371-2227 Panel Harness As (EUI EMCP 4.2 Interface Harness) (4) 155-2264 Connector Plug As (EP-C1 Plug) (5) 3E-3388 Connector Receptacle As (LD-C1 8 Pin Receptacle)

3. Locate the EMCP 4.2 panel (1) and harness, remove the top cover of the panel box or side extension top cover (depending on the location of the EMCP control) to gain access to the harness. Refer to Illustration 2 and 3.

4. Disconnect the 155-2264 Connector Plug As (EP-C1) (4) from the 3E-3388 Connector Receptacle As (LD-C1) (5). Inspect the EP-C1 plug assembly on the EMCP harness to ensure that the wire G408-BK is connected to pin 1 and the wire G407-RD is connected to pin 2 of the 3E-3388 Connector Receptacle As (LD-C1). Refer to Illustration 3.

5. If wires G408-BK and G407-RD are not in the right location on the LD-C1 connector, use screwdriver to swap the wires.

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Illustration 4	g03203361

6. Locate and open the AC/DC box and inspect the 372-6303 Generator Wiring Gp (RS485 remote annunciator) at the terminal block (the red and the black wire).

7. If wires are not in the right location, remove the wires and install them in proper locations as shown in illustration 4.

8. Perform a continuity test on the two RS-485 wires (the red and the black wires) coming from the EP-C20 (70 Pin) connector located in the back of the EMCP4.2 panel (illustration 3) to the AC/DC box terminal block (Illustration 4) to make sure that the wiring is correct.

9. Perform the following to restore the generator to the proper operational condition:

   1. Reconnect the battery cables and close the control circuit breaker for the AC power supply to the battery charger.

   2. Install and secure the battery charger cover.

   3. Energize the battery charger, confirm proper operation and functionality of the battery charger.

   4. Restore the generator set to the proper operational condition and reconnect the power supply.