Operating Instructions for the 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp {1421} Caterpillar

Engine:

3606 (S/N: 8RB1-UP)

3608 (S/N: 6MC1-UP)

3612 (S/N: 2NZ1-UP; 9FR1-UP; 9RC1-UP)

3616 (S/N: 1FN1-UP; 1PD1-UP)

3618 (S/N: 2MW1-UP)

3612 DI TA (S/N: NZA1-UP)

Introduction

This Special Instruction covers the use, the maintenance, and the troubleshooting of the 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp .

The 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp supply 24 VDC to the following governors:

• the 7C-8920 Governor Control

• the 147-7293 Governor Control As

Note: A direct connection to a customer provided 24 DCV Power Supply can also be used in order to provide power to the 7C-8920 Governor Control and 147-7293 Governor Control As .

The 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp accept either of the following input voltage ranges:

• 110 ACV to 127 ACV (50 Hz or 60 Hz)

• 200 ACV to 240 ACV (50 Hz or 60 Hz)

The 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp have an output voltage range of 22 DCV to 27 DCV.

The 4P-4788 Electrical Converter Gp is equipped with a backup battery. This battery backup is located in the enclosure. When AC power is interrupted, this battery backup can supply power to the electronic governor for a period of 40 minutes to 60 minutes. This time period is determined by the age of the battery.

The 4P-4789 Electrical Converter Gp is not equipped with a backup battery. Customer supplied batteries can be connected to the 4P-4789 Electrical Converter Gp . When customer supplied batteries are connected to the 4P-4789 Electrical Converter Gp , the 4P-4789 Electrical Converter Gp has the same functionality as the 4P-4788 Electrical Converter Gp .

Note: When emergency backup power is not required, customer supplied batteries do not need to be connected to the 4P-4789 Electrical Converter Gp . Without a backup battery, the 4P-4789 Electrical Converter Gp will act the same as an AC to DC power supply.

Specifications

Power Supply Pinout Specifications

Mounting

The 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp are shipped loose. The installation of the 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp are the responsibility of the customer. The installation location should be as close to the Governor Control as possible.

Wiring

After the 4P-4788 Electrical Converter Gp or the 4P-4789 Electrical Converter Gp has been installed, the customer must complete the wiring.

Except for the following two applications, all wire that is used for interconnect wiring should be 16 AWG:

• All wire that is used for external battery wiring should be at least 12 AWG.

• All wire that is used for Governor Control wiring should be at least 12 AWG.

Note: If any external battery wiring or Governor Control wiring needs to be run over 6.1 m (20 ft), 10 AWG wire should be used instead of 12 AWG wire. Check the local codes for insulation type.

Components

Enclosure

An IP55 enclosure houses the following components:

• Power Supply Module

• Transformer

• Batteries

The front panel of the enclosure provides a mounting location for the Governor Control Switch and the Lamp Assembly.

Governor Control Switch

The Governor Control Switch is used to energize the power relay. The power relay is located in the power supply module. When the Governor Control Switch is "On", the power relay is energized and power is provided to the governor control and the accessories. When the Governor Control Switch is "Off", the power relay is de-energized and no power is provided to the governor control or to the accessories.

Note: When there is no AC power and the engine is not running, the Governor Control Switch must be in the "Off" position. This will prevent the batteries from being discharged.

Lamp Assembly

The Lamp Assembly is mounted on the outside of the Converter Group Enclosure. The Lamp Assembly is connected to the following terminals:

• Accessories 2 Output Terminal 13

• Accessories 2 Output Terminal 14

The lamp will be ON whenever the Converter Group is supplying power to the Governor Control and to the accessories.

Power Supply Module

Illustration 1	g00836642
Power Supply Module

The Power Supply Module consists of the following components:

• rectifiers and filter capacitor

• regulated power supply (27 DCV)

• three LED indicators

• power relay

• alarm relay

• fuses

All of the above interconnections are terminated on the Power Supply Module.

Rectifiers and Filter Capacitor

The rectifiers and the filter capacitor take the reduced AC voltage from the transformer. The rectifiers and filter capacitors then convert the AC voltage to a filtered 42 DCV signal.

Regulated Power Supply (Power Supply Board 2)

The regulated power supply converts the filtered 42 DCV signal to a regulated 27 DCV signal.

LED Indicators

The LED Indicators are used to indicate the mode of the power supply:

• The Green LED indicator that is labelled "Mains Operation" indicates that normal DC power is available.

• The Red LED indicator that is labelled "Battery Charger" indicates that the regulated power supply is supplying charging current to the battery.

• The Red LED indicator that is labelled "Battery Operation" indicates that normal DC power is not available. The backup battery is supplying the current for the governor and for the accessories.

Note: Normal DC power is created from the AC Input voltage.

Power Relay

The Power Relay is located in the Power Supply Module. The Power Relay has a single Normally Open (N.O.) contact. When the governor control switch is in the "ON" position, the N.O. contact makes ONE of the following connections:

• connects the 27 DCV (from the normal power supply) to the governor and to the accessories

• connects the 24 DCV (from the battery) to the governor and accessories

In order for the Power Relay to be energized, the following parameters must be met:

• either the 27 DCV (from the normal power supply) or the 24 DCV (from the battery) must be present

• the Governor Control Switch must be in the "ON" position.

If the power relay is not energized, there will be no power available for the Governor Control or for the accessories.

Alarm Relay

The Alarm Relay is located in the Power Supply Module. The Alarm Relay has a "Form C" set of contacts. These contacts are connected to the following terminals:

• Terminal 15

• Terminal 16

• Terminal 17

When the power supply is operating on the normal AC power supply,Terminal 15 and Terminal 16 have continuity. When the power supply is operating on the battery backup, Terminal 15 and Terminal 17 have continuity.

Fuses

Five fuses are used in the Power Supply Module. Two fuses are used to protect the AC inputs. Three fuses are used to protect the DC outputs.

Two 4P-9241 Fuses are used to protect the AC inputs. In order to protect the 120 ACV - 127 ACV input, one fuse is connected between Terminal 1 and Terminal 18. In order to protect the 200 ACV - 240 ACV input, one fuse is connected between power supply module Terminal 3 and power supply module Terminal 18. Since only one input is used, the remaining fuse is effectively a spare.

Two 4P-9243 Fuses are used to protect the accessory outputs. One fuse is connected between the power relay's N.O. contact and Accessory Output 1 (Power Supply Module Terminal 11). The second fuse is connected between the power relay N.O. contact and Accessory Output 2 (Power Supply Module Terminal 13).

One 4P-9239 Fuse is used to protect the Governor Supply Output. This fuse is connected between the power relay's N.O. contact and the Governor Supply Output (Power Supply Module Terminal 9).

Transformer

The transformer is connected to the Power Supply Module. The transformer's high voltage side is connected to the following terminals: Terminal 18, Terminal 19 and Terminal 20. The transformer's low voltage side is connected to Terminal 24 and Terminal 25.

Batteries

Two 4P-9237 Batteries are wired in series in order to provide a 24 DCV backup battery power source. These batteries are rechargeable dry cell batteries with a 5.7 Ah capacity rating. Fully charged batteries can operate the Governor Control and the Governor Control accessories for a time period of 40 minutes to 60 minutes.

Maintenance

Start-Up

1. Check all wires and check all terminal points.

2. Tighten all termination points.

3. Perform Battery - Check. Refer to ""Battery - Check" ".

Every Three Months

1. Check all wires and check all terminal points.

2. Tighten all termination points.

3. Perform Battery - Check. Refer to ""Battery - Check" ".

Yearly

1. Check all wires and check all terminal points.

2. Tighten all termination points.

3. Perform Battery - Check. Refer to ""Battery - Check" ".

4. Clean the panel.

Calibration

The 4P-4788 Electrical Converter Gp and the 4P-4789 Electrical Converter Gp have been calibrated by the supplier. There is no need for any further adjustments.

Tests

Illustration 2	g00840853
System block diagram

Battery - Check

This test must be done with fully charged batteries. Ensure that the converter has been operating on normal power for at least 24 hours.

This test may cause the governor to lose control power. Perform this test only when an engine shutdown can be tolerated.

1. Start the engine.

2. Remove the input fuse holders. Removal of the input fuse holders will simulate the loss of the AC power source.

3. The power supply adapter should switch over to the backup battery. When the power supply adapter switches to battery backup, the following events will occur:
   • "Mains Operation" Indicator will turn off.

   • "Battery Charger" Indicator will turn off. (Note: If the battery is charged, the "Battery Charger" Indicator may already be off.)

   • "Battery Operation" Indicator will turn on.

4. If the engine does not operate normally for 40 minutes, replace the batteries and retest. If the engine operates normally for 40 minutes, replace the fuse holders.

Transformer - Test

1. If AC Supply Voltage is between 100 ACV and 127 ACV, measure Terminal 1 and Terminal 2. The voltage that is measured should be between 100 ACV and 127 ACV. If AC Supply Voltage is between 200 ACV and 240 ACV, measure Terminal 3 and Terminal 4. The voltage that is measured should be between 200 ACV and 240 ACV. If the voltages that are measured do not fall within the range, there is an AC source problem. Correct the AC source problem.

2. If AC Supply Voltage is between 100 ACV and 127 ACV, measure Terminal 18 and Terminal 19. The voltage that is measured should be between 100 ACV and 127 ACV. If AC Supply Voltage is between 200 ACV and 240 ACV, measure Terminal 18 and Terminal 20. The voltage that is measured should be between 200 ACV and 240 ACV. If the voltages measured do not fall within range, go to ""Fuse - Test" ". Test the input fuses.

3. Measure the AC voltage at Terminal 24 and Terminal 25. The AC voltage that is measured at Terminal 24 should be between 33 ACV and 42 ACV.
   • If the AC voltage at Terminal 24 and Terminal 25 is between 33 ACV and 42 ACV, the transformer is OK. STOP.

   • If the AC voltage at Terminal 24 and Terminal 25 is 0 ACV, the transformer is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

4. Disconnect Wire 24 from Terminal 24. Disconnect Wire 25 from Terminal 25. Measure the voltage at Wire 24 and Wire 25.
   • If the voltage that is measured at Wire 24 and Wire 25 is between 33 ACV and 42 ACV, the transformer is OK. Reconnect Wire 24 and Wire 25. STOP.

   • If the voltage at Wire 24 and Wire 25 is less than 33 ACV, the transformer is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

Rectifier and Capacitor Test

1. Measure the voltage at Terminal 22 (-) and Terminal 23 (+).
   • If the voltage at Terminal 22 (-) and Terminal 23 (+) is greater than 42 DCV, the rectifiers and the capacitor are OK. STOP.

   • If the voltage at Terminal 22 (-) and Terminal 23 (+) is less than 42 DCV, Power Supply Board 1 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

2. Disconnect Wire 22 from Terminal 22. Disconnect Wire 23 from Terminal 23. Measure the voltage at Wire 22 (-) and Wire 23 (+).
   • If the voltage at Wire 22 (-) and Wire 23 (+) is greater than 42 DCV, the rectifiers and capacitor are OK. Reconnect Wire 22 and Wire 23. STOP.

   • If the voltage at Wire 22 (-) and Wire 23 (+) is less than 42 DCV, Power Supply Board 1 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

Power Supply Board 2 - Test

1. Measure the voltage at Terminal 21 (+) and Terminal 22 (-).
   • If the voltage at Terminal 21 (+) and Terminal 22 (-) is between 26 DCV and 28 DCV, Power Supply Board 2 is OK. STOP.

2. Disconnect Wire 21 from Terminal 21. Disconnect Wire 22 from Terminal 22. Measure the voltage at Wire 21 (+) and Wire 22 (-).
   • If the voltage at Wire 21 (+) and Wire 22 (-) is between 26 DCV and 28 DCV, Power Supply Board 2 is OK. Reconnect Wire 21 (+) and Wire 22 (-). STOP.

   • If the voltage at Wire 21 (+) and Wire 22 (-) is not between 26 DCV and 28 DCV, Power Supply Board 2 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

Power Supply Board 1 - Test

Before performing this test, ensure that the following parameters are met:

• AC source voltage is present.

• The Governor Control Switch is in the "ON" position.

1. Measure the voltage at Terminal 7 (+) and Terminal 8 (-).
   • If the voltage at Terminal 7 (+) and Terminal 8 (-) is between 26 DCV and 28 DCV, check the Governor Switch and/or repair the Governor Switch.

   • If the voltage at Terminal 7 (+) and Terminal 8 (-) is between 26 DCV and 28 DCV, check the wiring and/or repair the wiring.

2. Measure the voltage at Terminal 9 (+) and Terminal 8 (-).
   • If the voltage between Terminal 9 (+) and Terminal 8 (-) is 0 DCV, proceed to ""Fuse - Test" ". Check the related fuse. Repeat Step 2.

   • If the voltage between Terminal 9 (+) and Terminal 8 (-) is between 26 DCV and 28 DCV, Power Supply Board 1 is OK. STOP.

   • If the voltage between Terminal 9 (+) and Terminal 8 (-) is not between 26 DCV and 28 DCV, Power Supply Board 1 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

3. Measure the voltage at Terminal 11 (+) and Terminal 12 (-).
   • If the voltage between Terminal 11 (+) and Terminal 12 (-) is 0 DCV, proceed to ""Fuse - Test" ". Check the related fuse. Repeat Step 2.

   • If the voltage between Terminal 11 (+) and Terminal 12 (-) is between 26 DCV and 28 DCV, Power Supply Board 1 is OK. STOP.

   • If the voltage between Terminal 11 (+) and Terminal 12 (-) is not between 26 DCV and 28 DCV, Power Supply Board 1 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

4. Measure the voltage at Terminal 13 (+) and Terminal 14 (-).
   • If the voltage between Terminal 13 (+) and Terminal 14 (-) is 0 DCV, proceed to ""Fuse - Test" ". Check the related fuse. Repeat Step 2.

   • If the voltage between Terminal 13 (+) and Terminal 14 (-) is between 26 DCV and 28 DCV, Power Supply Board 1 is OK. STOP.

   • If the voltage between Terminal 13 (+) and Terminal 14 (-) is not between 26 DCV and 28 DCV, Power Supply Board 1 is bad. Contact the Caterpillar Large Engine Center (LEC) for information on obtaining repair parts. The Caterpillar LEC can be reached at the following locations. Phone: 765-448-2400, Fax: 765-448-2300, E-mail: applicationsupport@cat.com, Internet: http://applicationsupport.cat.com.

Fuse - Test

To replace the fuse, perform the following steps.

1. Open the panel door.

2. Remove the appropriate fuse holder.

3. Use an ohmmeter to test the fuse.

4. If the fuse has continuity, reuse the fuse. If the fuse does not have continuity, replace the fuse with a new fuse.

5. Reinstall the fuse holder.

Procedures

Battery Replacement

Note: Batteries must be replaced in pairs.

1. Remove the plate that retains the batteries.

2. Disconnect the battery leads.

3. Slide the old batteries from the battery holder.

4. Insert the new batteries.

5. Reconnect the battery leads.

6. Replace the plate that retains the batteries.