Emergency Stop Circuit Improvement for the Electronic Instrument Panel to Control Engine Restart{7451} Caterpillar

Engines:

3508B (S/N: 1TW1; 2BM1; 2HW1; 3DM1; 3DW1; 3LS1; 3PS1; 3TS1; 4GM1; 5PS1; 5XM1; 6PN1; 7SM1)

3512B (S/N: 1PW1; 2EZ1; 2GW1; 2RD1; 2TD1; 3MS1; 3RS1; 3WS1; 3ZW1; 4AW1; 4TN1; 5AW1; 6PM1; 6WN1; 7HM1; 8EM1; 8RM1)

3516B (S/N: 1NW1; 2JW1; 2FW1; 3CW1; 3NS1; 3SS1; 3XS1; 4BW1; 6HN1; 6HZ1; 7KM1; 7RN1; 8CN1; 8KN1; 9AN1)

Introduction

This Special Instruction will modify the emergency stop circuit on the Electronic Instrument Panel. The existing circuit will allow the engine to restart after the emergency stop button is reset. The modification will change the circuit so that the Engine Control Switch must be reset after an emergency stop shutdown in order to restart the engine.

This modification is recommended for the 3500B engines that are used in the following applications: marine propulsion, marine auxiliary with the Electronic Instrument Panel (EIP), land and offshore petroleum engines with the EIP and land EPG with the EIP. This modification is not for the EMCP II/II+ generator sets.

This Special Instruction contains the procedures for modifying engines with premium wiring and for modifying engines with standard wiring. Verify which wiring package (standard or premium) that your engine has, and follow the corresponding procedures.

Description and Function

This modification changes the emergency stop circuit. The change will require the Engine Control Switch (ECS) to be reset after an emergency stop shutdown in order to start the engine. The current emergency stop circuit will initiate cranking after the emergency stop button is reset without resetting the ECS. Once the modification is installed, pushing the emergency stop button will remove power from the Primary Engine Control Module (PECM) relay and the Secondary Engine Control Module (SECM) relay. The PECM relay then removes power from the Primary ECM. The SECM relay removes power from the Secondary ECM. The emergency stop lockout relay and the emergency stop relay energize in order to complete the circuit for the PECM relay and the SECM relay. These relays stay energized until the ECS is placed in the OFF/RESET position. Resetting the emergency stop switch will not allow the engine to start until the ECS has been placed in the OFF/RESET position, and then to START or AUTO.

Glossary of Terms

ADEM Box - The ADEM box contains the PECM and the SECM. The premium wiring and instrumentation package contains the ADEM box.

Engine Control Module (ECM) - The ECM is referred to as the ADEM II on 3500B engines.

Engine Control Switch (ECS) - The ECS is located on the EIP or on the ADEM box. The ECS is the master control for the engine.

Emergency Stop - An emergency stop is a method to shutdown the engine in an emergency. An emergency stop shutdown is not used for routine engine shutdowns.

Electronic Instrument Panel (EIP) - The EIP is used with standard wiring on the following applications: marine, marine auxiliary, petroleum and land based package generator sets.

Engine Monitoring System (EMS, EMS-II and EMS-III) - This module is used to indicate up to ten alarms and shutdowns. The module will also indicate a numeric value for various engine parameters on an LCD display.

Independent Shutdown Relay (ISDR) - The ISDR is a means for the customer to supply 24 VDC to a separate relay specifically dedicated to shutting down the engine control modules. Completion of this Special Instruction, REHS0589, will make the ISDR a latching feature. Activating the ISDR will then require resetting the ECS prior to restarting the engine. Energizing the ISDR will not activate the air shutoffs.

PECM - Primary Engine Control Module

SECM - Secondary Engine Control Module. The SECM is used for applications in marine propulsion.

Threaded Insert - The threaded insert is a fastener that compresses during installation. The fastener can be installed permanently from one side of a panel.

Emergency Stop Lockout Relay - This relay will remove power from the PECM relay and the SECM relay until the ECS is returned to OFF/RESET and then moved to START.

Emergency Stop Relay - This relay is controlled by the emergency stop lockout relay. The emergency stop relay switches power to the PECM and the SECM relay.

Premium Wiring - The following components are designed to comply with marine requirements: harness, ECM, instrument panel and power distribution box.

Standard Wiring - The electrical harness and the EIP that are used for standard applications.

Installation

Rework Procedure

Standard Wiring Installation

1. Remove all electrical power from the engine and from the control panel. Verify that the 24 VDC power supply is disconnected.

2. Open the front panel of the EIP. Locate the EIP internal harness.

3. Locate the conductor that connects the emergency stop contact 1 to the Primary Engine Control Module Relay (PECMR) pin 86. Disconnect both ends of this conductor. If the engine has two engine control modules, disconnect the wire that is connected to pin 86 of the Secondary Engine Control Module Relay (SECMR). Remove the conductor from the existing harness.

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Illustration 1	g00656905
Subpanel in EIP for B-Series engines with standard harness. This illustration is not to scale. (1) Top left hand corner of subpanel (2) Drill two 1/4 inch holes for installing threaded inserts.

4. Use Illustration 1 to mark the location for two holes (2). Use a 1/4 inch twist drill in order to drill the two holes into the EIP subpanel.

5. Use the 178-7635 Installation Tool to install the 176-1691 Threaded Insert . Thread the insert all the way up the mandrel. Place the insert in the hole that was drilled in Step 4. Hold the tool with a box wrench and turn the mandrel with another box wrench until the insert is installed. Install an insert in each hole that was drilled in Step 4.

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Illustration 2	g00656743
(3) New wiring harness

6. Lay the new wiring harness (3) (complete with attached parts) over the existing EIP internal harness. Place the emergency stop contact block over the emergency stop switch. Place the relays in the area of the holes that were drilled in Step 4.

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Illustration 3	g00656764
Relays attached to EIP subpanel.

7. Attach the relays to the EIP subpanel by using the following items: 7S-1197 Screw , 3B-4501 Lockwasher and 4B-4863 Washer . The relay must be installed directly on top of the insert nut. The top lip of the nut must take the torque load of the 8-32 screw. Refer to Illustration 3 for a view of the relays on the EIP subpanel.

8. If the engine uses two engine control modules, skip this step and proceed to Step 10. If the engine uses only one ECM, find the "SECMR 86" conductor (4) in the new harness. The "SECMR 86" conductor is a short jumper from the "PECMR 86" conductor. Remove the "SECMR 86" conductor by cutting the wire at the base of the terminal lug that will connect to pin "PECMR 86".

9. Slide a 50 mm (2 inch) piece of 9X-8248 Heat Tube over the end of the wire that was clipped. Heat the tube until a tight seal is formed.

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Illustration 4	g00656766
(4) SECMR conductor

10. If the engine uses one ECM, skip this step and go to Step 11. If the engine uses two engine control modules, connect the "SECMR 86" conductor (4) to pin 86 of the SECM relay.

11. Connect the "PECMR 86" conductor of the new harness to pin 86 of the PECM relay.

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Illustration 5	g00656769
(5) Terminal 20 of the ECS

12. Connect the harness conductor with the label "EMSSS-20" to lug 20 (5) of the ECS.

13. Locate the new emergency stop switch block. The emergency stop switch block is attached to two leads on the new harness. There will be two additional leads at the same point of the harness with the labels "ES-1" and "ES-2".

14. Loosen the outer screws that are holding the emergency stop switch block. Install the new emergency stop switch block on the existing emergency stop switch. Place the new block opposite the existing block.

15. Verify that the new block is seated properly. Verify that the new block is actuated by the emergency stop button. Tighten the screws in order to secure the switch blocks.

16. Verify that the new harness conductors are connected to pins 7 and 8 of the new emergency stop switch block by checking the labels on each harness conductor. Connect the conductors with the labels "ES-1" and "ES-2" to pins 1 and 2 of the emergency stop switch. The conductors that are located at the terminals of the switch block identify these pins.

17. Connect the terminal with the label "TB-2" to any open pin in the terminal block with the label "200". The terminal block is the common line for the emergency stop relay and the emergency stop lockout relay.

18. This completes the installation process for standard wiring. Proceed to ""Operational Check" ".

Premium Wiring Installation

1. Remove all electrical power from the engine and from the control panel. Verify that the 24 VDC power supply is disconnected.

2. Open the front panel of the EIP.

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Illustration 6	g00656774
(1) ECS knob

3. Remove the knob (1) on the front of the ECS.

4. Remove the four screws that secure the ECS to the door of the EIP. Remove the switch from the door.

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Illustration 7	g00656794
(2) Emergency Stop Switch (3) Engine Control Switch (ECS) (4) Shutdown Notify Relay (5) Independent Shutdown Relay (6) Customer Power Relay (7) General Alarm Relay

5. Place the new 175-5042 Relay Group over the old harness on the inside of the EIP door. Place the emergency stop block over the emergency stop switch. Align the plate over the holes that are used for the ECS (3) in the EIP door. Orient the plate so that the ECS is between the new relays and the old relays. Refer to Illustrations 8 and 9.

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Illustration 8	g00656814
Slide the plate in the direction of the arrow for installation.

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Illustration 9	g00656820
(8) Relay group

6. Install the ECS. Tighten the four screws that hold ECS to the door of the EIP. Verify that the new plate is securely mounted to the inside of the door.

7. Determine if the EIP is equipped with an Independent Shutdown Relay (ISDR). This is accomplished by inspecting the interior of the EIP and locating the harness leads with the label "ISDR-XX". "XX" represents a pin number such as 86 or 85. The labels will be below the ECM relays. Marine auxiliary generators seldom use the ISDR. Most marine propulsion engines with premium wiring use the ISDR.

8. If the EIP contains the ISDR, proceed to Step 12. If the EIP does NOT contain the ISDR, continue with this step. Locate the push-on terminal lug with the conductor with the label "ISDR-30 ESLR-87" in the new harness. This terminal lug is intended for connection to pin 87 of the emergency stop lockout relay. There are two leads exiting this terminal lug. Cut the "ISDR-30 ESLR-87" lead from the terminal lug. Cut the wire close to the terminal lug. The conductor will not be used because there is no ISDR. Remove the "ISDR-30 ESLR-87" conductor from the new harness bundle.

9. Slide a 30 mm (1.2 inch) length of 9X-8248 Heat Tube over the end of the terminal lug that was cut in Step 8. Heat the tube until a tight seal is formed.

10. Locate the "ES-8 ISDR-87" conductor in the new harness. Disconnect the terminal lug from pin 8 of the new emergency stop switch contact. Remove the "ES-8 ISDR-87" conductor from the new harness.

11. Remove the terminal that is connected to pin 1 of the emergency stop switch. The other end of this conductor is connected to pin 86 of the PECM relay. Remove the terminal from pin 86 of this relay. Remove this entire conductor from the existing harness.

12. If the EIP does NOT contain the ISDR, go to Step 15. If the EIP does have an ISDR, continue with this step. Locate the ISDR and remove any terminal lugs that are connected to pins 30 and 87 of the ISDR. The other end of the conductor that is connected to pin 30 of the ISDR is connected to pin 1 of the emergency stop button. Remove this terminal lug from pin 1 of the emergency stop button. Remove this conductor from the existing harness.

13. Remove the terminal that is connected to pin 87A of the ISDR. The other end of this conductor is connected to pin 86 of the PECM relay. Disconnect the terminal from pin 86 of the PECM relay and from pin 86 of the SECM relay. Remove this entire conductor from the existing harness.

14. Connect the leads with the labels "ES-8 ISDR-87" and "ISDR-30 ESLR-87" from the new harness to pins 87 and 30 of the ISDR. Connect the conductors to pin 8 and ESLR pin 87 on the emergency stop switch. Connections will be made to pins 86 of the PECM relay and the SECM relay in a later step.

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Illustration 10	g00656824
(9) 9X-8248 Heat Tube

15. Locate the shutdown notify relay. Remove the terminal lug that is attached to pin 85 of the relay. Slide a 65 mm (2.5 inch) length of 9X-8248 Heat Tube (9) over this wire. Connect the male terminal lug from the new harness to the female lug that was removed from pin 85 of the shutdown notify relay.

16. Slide the heat shrink tubing over both terminal lugs. Heat the tube until a tight seal is formed.

17. Connect the lead with the label "ESLR-85 SDNR-85" to pin 85 of the shutdown notify relay.

18. Locate the PECM relay and the SECM relay. Connect the new harness conductor with the label "ESR-87A PECMR-86" to pin 86 of the PECM relay. Connect the new harness conductor with the label "PECMR-86 SECMR-86" to pin 86 of the SECM relay.

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Illustration 11	g00656847
(10) ES-1 ESR-30 Conductor, connect to pin 1 of the Emergency Stop Switch (11) EMSS-20 ES-7 Conductor, connect to pin 20 of the Engine Control Switch

19. Locate the rear of the ECS. Remove the screw on terminal 20 of the switch. Connect the new harness conductor (11) with the label "EMSS-20 ES-7" to pin 20 of the ECS. Install and tighten the screw on terminal 20.

20. Locate the new emergency stop switch block. The emergency stop switch block is attached to at least two leads of the new harness. There will be an additional lead with the label "ES-1" at the same point of the harness. Connect the conductor (10) with the label "ES-1 ESR-30" to pin 1 of the emergency stop switch. The new emergency stop switch block contains contacts 7 and 8. These contacts are shown in the schematic for the new emergency stop switch.

21. Loosen the outer screws that are holding the emergency stop switch block. Install the new emergency stop switch block on the existing emergency stop switch. Place the new block opposite the existing block.

22. Verify that the new block is seated properly. Verify that the new block is actuated by the emergency stop button. Tighten the screws in order to secure the switch blocks.

23. Verify that the new harness conductors are connected to the appropriate terminals on the emergency stop switch. Engines that are equipped with an ISDR will have two connections on pin 8 of the emergency stop switch. The remaining conductors of the new harness are connected to the relays. The emergency stop lockout relay is the relay that is closest to the ECS. The emergency stop relay is the other relay on the plate. Each conductor in the new harness has a label. Verify that each of the conductors is connected to the proper relay terminal.

Operational Check

1. Verify that all wires are connected in accordance with the instructions in this procedure. Pull out the emergency stop button to the RESET position. Move the ECS to the OFF/RESET position.

2. Apply 24 VDC power to the engine and to the control panel.

3. Turn the ECS to the MANUAL START position. Run the engine at normal idle speed.

4. Press the emergency stop button. Emergency stop should be indicated on the EMS. Allow the engine to coast to zero RPM.

5. Pull out the Emergency Stop button to the RESET position. Observe engine operation. The engine must not crank.

6. Turn the ECS to OFF/RESET. Turn the ECS to the MANUAL START position. The engine should crank. Run the engine at normal idle speed.

7. Press the emergency stop button. Emergency stop should be indicated on the EMS. Reset the emergency stop button before the engine falls below 400 RPM. The engine should continue to coast to zero RPM.

8. If the engine does not have an ISDR, go to Step 10. Locate pins 7 and 8 on the customer data connector. The pins have the label "Independent Shutdown Drive". When you apply 24 VDC to these pins, the ISDR will energize. Connect a 24 VDC power supply with an amperage rating of at least 200 mA to the pins. Leave the circuit open at this time. Voltage will be applied in a later step.

9. Turn the ECS to OFF/RESET and then to MANUAL START. Run the engine at normal idle speed. Apply 24 VDC to the independent shutdown drive pins 7 and 8 for one second. Observe engine operation. The engine should come to a complete stop.

10. Turn the ECS to the OFF/RESET position.

11. Turn the ECS to the MANUAL START position. The engine should crank and the engine should operate normally. This completes the operational check.

Final Assembly

1. Secure the new harness to the existing harness with 3S-2093 Cable Straps .

2. Ensure that all connections are properly torqued. Verify that all electrical connectors are completely connected.

3. Close the EIP door and return the ECS to the desired position.

Maintenance

Theory of Operation

Pressing the emergency stop button causes 24 VDC to energize the emergency stop lockout relay and the emergency stop relay. Energizing the emergency stop relay removes power from the coil of the PECM relay and SECM relay. Removing power from the coil will remove supply voltage to the ECM. A circuit is completed between pin 87 and pin 30 of the emergency stop lockout relay when the emergency stop lockout relay energizes. The circuit will remain complete until 24 VDC is removed from the coils of the ESLR and the ESR. This is accomplished by moving the ECS to the OFF/RESET position.

Note: The air shutoffs are also activated when the emergency stop button is pressed. If the engine is equipped with an ISDR, energizing this relay will cause the same lockout to occur. The air shutoffs will NOT activate if the ISDR energizes. The ECS must be turned to the OFF/RESET position to remove the lockout condition.

Troubleshooting

Pressing the emergency stop button does not cause the engine to stop.

• Ensure that the emergency stop lockout relay and the emergency stop relay coils are energizing when the emergency stop button is pressed. Measure the voltage at the coils of the emergency stop lockout relay and the emergency stop relay. If 24 VDC is measured across the coils, there may be a wiring problem or damaged relays. If no voltage is measured, ensure that 24 VDC is supplied to the emergency stop lockout relay and the emergency stop relay from pin 86 on emergency stop contact 8.

The engine will not start.

• Ensure that the PECM relay and SECM relay have 24 VDC to the coils when the ECS is moved to MANUAL START. If this is not the case, work backward through the voltage supply by checking for 24 VDC with a multimeter. The emergency stop lockout relay and the emergency stop relay should not have 24 VDC during normal operation. Continue to check for voltage. Work back to pin 1 of the emergency stop switch.