Installation and Initial Start-Up Procedure for G3516B and G3520B Engines{1000} Caterpillar

Installation and Initial Start-Up Procedure for G3516B and G3520B Engines{1000}

Usage:

Generator Set:: G3516B (S/N: ZBB1-UP; CME1-UP; ZBC1-UP; CSC1-UP); G3520B (S/N: CWD1-UP; GZP1-UP)
Power Module:: PMG3516 (S/N: CFD1-UP)
Engine:: G3516B (S/N: CEY1-UP; 7EZ1-UP); G3520B (S/N: BGW1-UP)

Introduction

Do not perform any procedure in this Special Instruction until you read this information and you understand this information.

This Special Instruction provides the following information for G3500B Engines:

Requirements for the electrical system
Proper welding practices
Grounding procedures
Required service tools
Electrical components and electronic components
Wiring connections and the corresponding functions that are available to the customer
Initial start-up procedures
Governor adjustment procedures

ReferenceInformation from the following sources will be needed for this Special Instruction:

Complete analysis of the fuel
Data from a complete fuel analysis that is entered into Caterpillar Software, LEKQ6378, "Methane Number Program"
The engine's performance data sheet from the engine's Technical Marketing Information (TMI)
Engine Operation and Maintenance Manual, SEBU7201
Generator set Operation and Maintenance Manual, SEBU7566
Power module Operation and Maintenance Manual, SEBU7647
Systems Operation/Testing and Adjusting, RENR2268
Troubleshooting Manual, RENR2270
The Troubleshooting Manual, RENR5927

Requirements for the Electrical System

All of the wiring must conform to all of the codes that are applicable to the site. When you route the wiring, avoid acute bends and sharp edges. To protect the wiring harnesses, route the harnesses through metal conduit. A liquid tight conduit is recommended. Use proper support and alignment in order to avoid strain on the conduit.

The engine control system requires a clean 24 VDC power supply. The maximum allowable AC ripple voltage is 150 millivolts AC peak to peak. For the wiring, the maximum allowable voltage drop is 1 VDC from the power supply to an Electronic Control Module (ECM) or to an actuator. The power supply must be capable of supplying 20 amperes of continuous power.

The power supply for the engine control system must be separate from the power supply for the starting motor.

Grounding Practices

Proper grounding is necessary for optimum engine performance and reliability. Improper grounding will result in electrical current paths that are uncontrolled and unreliable.

Uncontrolled electrical circuit paths can result in damage to main bearings, to crankshaft bearing journal surfaces, and to aluminum components. Uncontrolled electrical circuit paths can also cause electrical activity that may degrade the engine electronics and communications.

For the starting motor, do not attach the battery negative terminal to the cylinder block.
Use an electrical ground strap to connect all metal cases that contain electrical components or electronic components to the cylinder block.
Do not connect the negative terminal from the electrical power supply directly to the cylinder block. Connect the negative terminal from the electrical power supply to the negative terminal "−" on the engine mounted junction box.
Ground the cylinder block with a ground strap that is furnished by the customer. Connect this ground strap to the ground plane.
Use a separate ground strap to ground the battery negative terminal for the control system to the ground plane.
Rubber couplings may connect the steel piping of the cooling system and the radiator. This causes the piping and the radiator to be electrically isolated. Ensure that the piping and the radiator are continuously grounded to the cylinder block. Use ground straps that bypass the rubber couplings.
Ensure that all grounds are secure and free of corrosion.

Proper Welding Procedures

Proper welding procedures are necessary in order to avoid damage to electronic controls. Perform welding on the engine according to the following procedure.

Set the engine control to the "STOP" mode.

Turn OFF the fuel supply to the engine.

Disconnect the negative terminal from the battery.

Disconnect the engine's electronic components from the wiring harnesses: ECM, throttle actuator, actuator for the turbocharger compressor's bypass, fuel metering valve and sensors.

Protect the wiring harnesses from welding debris and/or from welding spatter.

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NOTICE

Do NOT use electrical components (ECM or ECM sensors) or electronic component grounding points for grounding the welder.

Connect the welder's ground cable directly to the engine component that will be welded. Place the clamp as close as possible to the weld in order to reduce the possibility of welding current damage to the engine bearings, to the electrical components, and to other engine components.

Use standard welding procedures to weld the materials together.

Service Tools

The tools that are listed in Table 1 are required in order to enable a service technician to perform the electrical installation procedures and the initial start-up.

The Caterpillar Electronic Technician (ET) is designed to run on a personal computer.

Cat ET can display the following information:

Parameters
Diagnostic codes
Event codes
Engine configuration
Status of the monitoring system

Cat ET can perform the following functions:

Perform diagnostic tests.
Calibrate sensors.
Download flash files.
Set parameters.

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Table 1
Service Tools
Pt. No.	Description	Functions
N/A	Personal Computer (PC)	The PC is required for the use of Cat ET.
"JERD2124"	Software	Single user license for Cat ET Use the most recent version of this software.
"JERD2129"	Software	Data subscription for all engines
171-4400 ⁽¹⁾	Communication Adapter Gp	This group provides the communication between the PC and the engine.
7X-1414	Data Link Cable As	This cable connects the communication adapter to the service tool connector on the engine.
237-7547	Adapter Cable As	This cable connects to the USB port on computers that are not equipped with a serial port.
8T-8726	Adapter Cable As	This cable is for use between the jacks and the plugs of the sensors.
151-6320	Wire Removal Tool	This tool is used for the removal of pins and sockets from Deutsch connectors and AMP connectors.
1U-5804	Crimp Tool	This tool is used for work with CE electrical connectors.
146-4080	Digital Multimeter	The multimeter is used for the testing and for the adjusting of electronic circuits.
7X-1710	Multimeter Probes	The probes are used with the multimeter to measure voltage in wiring harnesses without disconnecting the harnesses.
156-1060 or 156-1070	Emission Analyzer Tool	This tool is used to measure the level of emissions in the engine's exhaust. The 156-1060 measures the levels of four different compounds. The 156-1070 measures the levels of six different compounds. Either tool may be used.

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^( 1 )

The 7X-1700 Communication Adapter Gp may also be used.

Note: For more information regarding the use of Cat ET and of the PC requirements for Cat ET, refer to the documentation that accompanies your Cat ET software.

Connecting Cat ET

The engine's battery supplies the communication adapter with 24 VDC. Use the following procedure to connect Cat ET to the engine's control system.

Set the engine control to the OFF/RESET mode.

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Illustration 1	g01088745
(1) PC (2) 196-0055 Serial Cable or the 160-0141 Serial Cable (3) 171-4401 Communication Adapter II (4) 207-6845 Adapter Cable (5) 7X-1414 Data Link Cable

Connect cable (2) to the RS-232 serial port of PC (1) .
Note: If your PC is not equipped with a serial port, use the 237-7547 Adapter Cable As in order to connect to the USB port. Connect one end of the adapter to the end of cable (2). Connect the other end of the adapter to a USB port on the PC.

Connect cable (2) to communication adapter (3) .

Connect cable (4) to communication adapter (3) .

Connect cable (4) to cable (5) .

Connect cable (5) to the service tool connector on the engine mounted terminal box.

Set the engine control to the STOP mode. The engine should be OFF.
If Cat ET and the communication adapter do not communicate with the ECM, refer to Troubleshooting, "Electronic Service Tool Will Not Communicate With ECM".
For 20 cylinder engines, if Cat ET displays "Duplicate Type on data link. Unable to Service", check the harness code for the slave ECM.
The harness inside the terminal box for the slave ECM has a jumper wire (harness code) that connects terminals J3-29 and J3-60. The ECM that is connected to the harness reads the harness code. This allows the ECM to operate as the slave ECM. The jumper wire must be connected in order for Cat ET to communicate with the modules. The jumper wire must be connected in order for the engine to crank. The jumper wire must remain connected in order for the engine to run.
Check the continuity between terminals J3-29 and J3-60. Verify that the jumper wire is in good condition. Make repairs, as needed.

Terminal Box

Note: The terminal box is designed to remain mounted on the engine. The mounting hardware includes isolators. Do not move the terminal box to a remote location. Moving the terminal box could result in wiring problems and in reduction of the service life of the components inside the terminal box.

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Illustration 2	g00918443
Terminal box

The ECM is inside the terminal box. This terminal box provides the point of termination for all of the wiring that is related to the engine's sensors and for the ignition system. The terminal box's components are identified in Illustrations 3 and 4.

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Illustration 3	g01089034
The connectors on the terminal box connect the Electronic Control Module (ECM) to various engine controls, sensors, actuators, etc. (1) Emergency stop button (2) Connectors J16/P16 for the harness to the fuel metering valve (3) This connector is not used. (4) Connectors J14/P14 for the wiring to the starting motor (5) Connectors J13/P13 for the wiring to the gas shutoff valve (6) Service tool connector J23 for the Cat ET (7) Connectors J12/P12 for the harness to the analog sensors (8) Connectors J11/P11 for the harness to the detonation sensors (9) Connectors J10/P10 for the harness to the speed/timing sensor, to the throttle actuator, and to the oxygen buffer (if equipped) (10) 168-2028 Wiring Harness (11) Harness to the ignition transformers (12) Connectors J5/P5 for the harness to the Integrated temperature sensing module (13) This connector is not used. (14) Connectors J9/P9 for the wiring to the customer's connections

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Illustration 4	g01076361
Components inside the terminal box (15) Electronic Control Module (ECM) (16) ECM connector P2 (17) ECM connector P1 (18) Ground strap for the ECM (19) P50 connector for calibration of the speed/timing sensor (20) 16 amp circuit breaker for the engine (21) 6 amp circuit breaker for the switched +Battery

Note: A 168-2028 Wiring Harness (10) must be connected to the terminal box in order for the engine to operate.

Customer's Wiring

To properly wire the engine for the requirements of the specific application, the customer must be aware of several inputs and outputs that are associated with the ECM. The following list includes some examples of the inputs and outputs:

Emergency stop
Electrical power supply for the control system
Start-up and shutdown
Engine speed and governing
Status of engine operation

Interconnect wiring harnesses that are supplied by the factory include the wiring for most of the customer's inputs and outputs. Each wiring harness has a 47-pin connector. The 47-pin connector on the harness mates with the J9 connector on the bottom of the terminal box. The terminals on the 47-pin connector and the corresponding wires are identified in Illustration 5.

Some of the wiring connections are required. Some of the wiring connections are optional. The connections that are required are identified in Table 2. The connections that are optional are identified in Table 3.

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Illustration 5	g01088445
47-pin connector J9

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Table 2
47-pin connector J9 Connections that are Required
Terminal	Description	Interconnect Wiring Harness	Functions and Comments
B	Input for Emergency Stop	C256B-BK	These inputs must be connected together in order to run the engine. When these inputs are disconnected, the emergency stop shutdown will be activated. An emergency shutdown initiates the following events: The fuel is immediately turned off. The ignition is immediately turned off. For details, refer to "Wiring for the Emergency Stop Circuit".
h	Input for Emergency Stop	C256C-BK
C	Return for the Inputs	P500D-BK	These connections are used in order to provide a return for various input switches.
O	Return for the Inputs	P500E-BK
I	Input for the Desired Engine Speed "+"	M170-WH	An input for the desired engine speed is required. The input can be either 0 to 5 VDC or 4 to 20 mA. Terminals "I" and "J" are used to provide a 0 to 5 volt DC input for the desired engine speed. Terminal "I" must be in the same circuit as terminal "J". An input of 0 VDC causes the engine rpm to equal the value of the "Minimum High Idle Speed" parameter. An input of 5 VDC causes the engine rpm to equal the value of the "Maximum High Idle Speed" parameter.
J	Return for the Desired Engine Speed "−"	M170-BK
N	Driven Equipment Input	M000-WH	This input indicates when the driven equipment is ready. When this input is connected to terminal "C" or to terminal "O", the engine will follow the normal sequence for starting. When this input is not connected to terminal "C" or to terminal "O", the engine will not crank. An event code will be generated if this input is not connected to terminal "C" or to terminal "O" within a period of time that can be programmed with Cat ET. If the engine is running and this input is disconnected from terminal "C" or from terminal "O", the ECM will immediately shut down the engine by removing the voltage from the gas shutoff valve (GSOV). The engine cooldown will not occur.
Y	Input for the "AUTO" Mode	P614C-RD	If these inputs are not wired correctly, the ECM will activate a diagnostic code. If these inputs are controlled by the customer's equipment, the transitions between the inputs must occur within 1/10 second. All of these inputs must return through terminal "C" or through terminal "O". When terminal Y is connected to terminal "C" or to terminal "O", the ECM is in "STANDBY" mode. The engine's mode of operation is determined by terminal Z. When terminal Z is connected to terminal "C" or to terminal "O", the normal sequence for start-up is initiated. When terminal Z is disconnected from terminal "C" or from terminal "O", a normal shutdown is initiated. If the engine is running and terminal "d" is connected to terminal "C" or to terminal "O", the sequence for a normal shutdown is initiated. When terminal Z is connected to terminal "C" or to terminal "O", the normal sequence for start-up is initiated.
d	Input for the "STOP" Mode	P613C-BK
Z	Input for the "START" Mode	P615C-RD
j	Idle/Rated Input	M030-WH	When this input is not connected to terminal "C" or to terminal "O", the engine will run at the idle speed that has been programmed with Cat ET. When the engine oil pressure is greater than the setpoint for the engine speed and this terminal is connected to terminal "C" or to terminal "O", the engine will run at rated speed.
T	Input for Engine Stop	M010-WH	This input is not recommended for normal shutdown. Connecting terminal "d" to terminal "C" or to terminal "O" is the recommended method for initiating a normal shutdown. This input must be connected to terminal "C" or to terminal "O" in order for the engine to run. If the engine is shut down and this input is not connected to terminal "C" or to terminal "O", the engine will not crank. If the engine is running and this input is disconnected from terminal "C" or from terminal "O", the ECM will remove power from the GSOV. The cooldown does not operate. No diagnostic codes or event codes are provided for this input.
u	+ Battery	P100-RD	These connections are the primary connections for power to the control system.
x	- Battery	P300A-BK

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Table 3
47-pin connector J9 Connections that are Optional
Terminal	Description	Interconnect Wiring Harness	Functions and Comments
A	Fused 24 Volt DC Output	P600D-RD	This connection provides a fused 24 VDC power supply for the customer. The electrical power is provided by the ECM. This connection can provide a maximum of 6 amperes. This output is not provided when the ECM is in the "OFF/RESET" mode.
H	Output for the 5 Volt DC Desired Engine Speed	M170-RD	An input for the desired engine speed is required. The input can be either 0 to 5 volt DC or 4 to 20 mA. The method for the desired speed input must be selected with Cat ET. If the 0 to 5 volt DC input is selected, the input may be provided by a potentiometer. If a potentiometer is used to provide the 0 to 5 volt DC input for desired engine speed, this terminal provides +5 VDC for the potentiometer. The +5 VDC is created by the ECM.


K	"+" Input for the 4 to 20 mA Desired Speed Signal "+"	M500-WH	An input for the desired engine speed is required. The input can be either 0 to 5 volt DC or 4 to 20 mA. The method for the desired speed input must be selected with Cat ET. The 4 to 20 mA is an optional method for providing the desired engine speed input. If the 4 to 20 mA method is used to control the desired speed, the 0 to 5 volt DC input must be disabled. The 4 to 20 mA input is an isolated input. The "+" input must be in the same circuit as the "-" input. An input of 4 mA causes the engine rpm to equal the value of the "Minimum High Idle Speed" parameter. An input of 20 mA causes the engine rpm to equal the value of the "Maximum High Idle Speed" parameter.
P	"-" Input for the 4 to 20 mA Desired Speed Signal "−"	M500-BK
L	"Grid Status" Input	M020-WH	If the generator will be connected to a grid, this input must be used. This input changes the generator's "Grid Status" parameter to "ON" or "OFF". When this terminal is not connected to terminal "C" or to terminal "O", the "Grid Status" is "ON". The ECM governs the engine according to the "Governor Gain" parameters. When this terminal is connected to terminal "C" or to terminal "O", the "Grid Status" is "OFF". The ECM governs the engine according to the "Auxiliary Governor Gain" parameters.
M	Output for Engine Failure	P698C-WH	The ECM will activate this output when the ECM causes the engine to be shut down. When this output is activated, the output is connected to ground. This output is capable of sinking 0.3 amperes.
R	Crank Terminate	P696C-WH	The ECM activates this output when the engine's rpm increases to the crank terminate speed. The crank terminate speed can be programmed with Cat ET. This output remains activated until the engine's rpm drops to zero. When this output is activated, the output is grounded. This output is capable of sinking 0.3 amperes.
S	Input for "Desired Timing"	M050-WH	This input is provided in order to control the base timing of the engine. When this input is an open circuit, the engine will use the "First Desired Timing" as the desired timing. When this input is connected to terminal C or to terminal O, the engine will use the "Second Desired Timing" as the desired timing. Refer to the applicable Systems Operation, Testing and Adjusting for additional information on the "Desired Timing" parameters.
U	Output for Active Alarm	P697C-WH	This output is activated if the ECM detects an alarm condition. When this output is activated, the output is connected to ground. This output is capable of sinking 0.3 amperes.
V	Output for Run Relay	M040-WH	This output is activated when the engine is cranked. The output remains active until the beginning of engine shutdown. When this output is activated, the output is connected to ground. This output is capable of sinking 0.3 amperes.
X	Input from the Generator Output Power Sensor	S990-WH	This input is active only on 50 Hz generators. This input must be connected for 50 Hz applications. The ECM will activate a diagnostic code if this input is not connected for 50 Hz applications. This connection is provided in order to connect a wattmeter. The signal from the wattmeter is used to prevent the turbochargers from surging. The output from the wattmeter may vary from 0 to 5 volts DC.
c	Cat Data Link +	D100B-PK	These connections provide the means for communicating the status of the engine control system, of various engine components, and of sensors. The Cat data link can be connected to the Customer Communication Module (CCM). For information on connecting the CCM, refer to the most recent literature for the CCM. When the Caterpillar Software for the CCM is loaded on a personal computer, the program uses this data link in order to obtain engine information via the CCM.
g	Cat Data Link −	D100B-PU
p	Driver Output for the Gas Shutoff Valve	A330C-WH	This output may be used to control other gas valves that are supplied by the customer. This output is wired in parallel with the J13 connector for the GSOV that is mounted on the engine. When J13 is energized, 24 VDC and 2.0 amperes are available at this output.
s	Return for the Gas Shutoff Valve	A330C-BK
D	Unused	M900B-WH	These terminals are not used.
E		M900A-WH
F		SPO2-RD
G		SPO2-BK
t
w		C205C-WH
e
k
n

Wiring for the Emergency Stop Circuit

The emergency stop buttons must be properly wired in order to immediately stop the engine in case of an emergency situation. An emergency stop button is provided on the engine mounted terminal box.

If the emergency stop button is activated, the fuel is immediately shut off. Electrical power is immediately removed from the ignition system.

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NOTICE

Emergency shutoff controls are for EMERGENCY use ONLY. DO NOT use emergency shutoff devices or controls for normal stopping procedure.

The customer may supply additional emergency stop buttons. The contacts of the emergency stop button must be normally closed. Any additional customer supplied emergency stop buttons must be wired in series in order to operate properly. Operation of all emergency stop buttons must be verified during the initial start-up.

Illustration 6 is a wiring diagram of the emergency stop button on the engine mounted terminal box.

If the customer does not use the 47−pin P9 connector on the engine mounted terminal box, a jumper wire between terminals P9-B and P9-h is necessary.

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Illustration 6	g01088576
Schematic diagram for the emergency stop circuit inside the terminal box

Illustration 7 is a wiring diagram of the emergency stop button on the engine mounted terminal box and an additional customer supplied emergency stop button attached to the J9 connector.

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Illustration 7	g01088581
Schematic diagram for an emergency stop circuit with an emergency stop button that is supplied by the customer

Wiring for the Gas Shutoff Valve (GSOV)

The GSOV must be energize-to-run. The GSOV may be supplied by the customer or by Caterpillar. Usually, the GSOV is installed when the piping for the fuel is installed at the site. The GSOV may be controlled by the engine's control system or by the customer's equipment. The GSOV is also called the fuel control relay.

The ECM can supply a maximum continuous current of 1.5 amperes to the GSOV. A relay must be installed if the GSOV requires a continuous current that is greater than 1.5 amperes.

When the engine's control system controls the GSOV, the ECM supplies voltage to the GSOV. The valve opens in order to allow fuel to flow to the engine. When voltage is removed from the GSOV, the valve closes and the fuel flow stops.

When the customer's equipment controls the GSOV, the equipment must include the necessary logic in order to ensure that the GSOV opens and the GSOV closes at the appropriate times.

There are three options for wiring the GSOV. The options are described in the following paragraphs.

The GSOV is controlled by the customer's equipment. In this case, the circuit for the engine's control system must be a complete path. The circuit must include a resistor. Otherwise, an open circuit diagnostic code will be activated and the engine will not start. Refer to Illustration 8 for an example of this type of installation.

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Illustration 8	g01078576
The GSOV is controlled by the customer's equipment. In this configuration, the circuit must include a resistor. A typical installation is shown.

The GSOV is controlled by the engine's control system. The engine harness is used for the connection. The customer may supply an additional switch in the electrical circuit for the GSOV. Refer to Illustration 9 for an example of this type of installation.

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Illustration 9	g01088630
The GSOV is controlled by the engine's control system.

The GSOV is controlled by the engine's control system. The GSOV is connected to a harness that is provided by the customer. The customer may supply an additional switch in the electrical circuit for the GSOV. Refer to Illustration 10 for an example of this type of installation.

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Illustration 10	g01088638
The GSOV is controlled by the engine's control system. The GSOV is connected via a harness that is provided by the customer.

Wiring for Monitoring the Generator's Output Power

The ECM monitors the generator's output power in order to accurately control the air/fuel ratio. The ECM uses an output from one of the following sources in order to monitor the generator's output power:

Electronic Modular Control Panel II+ (EMCP II+)
Programmable Logic Controller (PLC)
Wattmeter

The PLC and the wattmeter are also called power sensors.

If the generator is equipped with the EMCP II+, information on the engine load is provided via the Cat data link. The wiring is installed at the factory. No additional connections are needed.

If the generator is not equipped with the EMCP II+, information on the engine load must be provided by a power sensor.

The power sensor's output to the ECM must be an analog signal with a range of 0 to 4.8 VDC. The power sensor's output must have a linear relationship with the generator's output power. The accuracy of the wattmeter's output must be within one percent of the generator's actual output power.

The engine's control system includes parameters that allow the ECM to accurately estimate the generator's output power. The values for these parameters are modified by using Cat ET. To identify the parameters for the wattmeter, Cat ET labels the parameters "Generator Output Power Sensor".

For details on these parameters, refer to Systems Operation, Testing and Adjusting, RENR2268, "Electronic Control System Parameters".

Illustration 11 is a wiring diagram for a typical power sensor.

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Illustration 11	g01088656
Schematic of the power sensor's input For the actual wiring, refer to the generator's schematic diagram. The potentiometer is optional. For further information, refer to Troubleshooting, "Ganerator Output Power Sensor - Calibrate".

Inputs for the Engine's Mode of Operation

The engine has four modes of operation. The mode of operation is determined by three inputs on the J9 connector. The valid configurations of the inputs are described in Table 4.

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Table 4
Valid Configurations of the Terminals for Selection of the Engine's Mode of Operation
	Terminal "Y"	Terminal "Z"	Terminal "d"
"OFF/RESET" Mode	No ⁽¹⁾	No	No
"AUTO" Mode	Yes ⁽²⁾	No	No
"START" Mode	Yes	Yes	No
"START" Mode	No	Yes	No
"STOP" Mode	No	No	Yes

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^( 1 )	The "No" indicates that the terminal is not connected to terminal "C" or to terminal "D".
^( 2 )	The "Yes" indicates that the terminal is connected to terminal "C" or to terminal "D".

Configurations that are not shown in Table 4 will activate a diagnostic code.

The transition between inputs must occur within 1/10 second. If the transitions do not occur within 1/10 second, a diagnostic code will be activated.

"OFF/RESET" Mode

When none of the inputs are connected, the engine is in the "OFF/RESET" mode. The ECM is off. Any active diagnostic codes are cleared.

"AUTO" Mode

When terminal "Y" is connected to terminal "C" or to terminal "O", the engine is in the "AUTO" mode. The ECM is in standby.

The engine start sequence will be initiated when terminal "Z" is connected to terminal "C" or to terminal "O". When terminal "Z" is disconnected, the shutdown sequence will be initiated. In the "AUTO" mode, terminal "Z" is used to control both the engine start sequence and the shutdown sequence.

"START" Mode

The engine start sequence will begin when terminal "Z" is connected to terminal "C" or to terminal "O".

"STOP" Mode

The shutdown sequence will begin when terminal "Z" is disconnected from terminal "C" or from terminal "O" and terminal "d" is connected to terminal "C" or to terminal "O". The shutdown sequence is followed by a cooldown period.

Initial Start-Up Procedure for Engines that are Equipped with Oxygen Feedback

Ensure that all of these factors are in proper working condition prior to the initial start-up: engine installation, driven equipment, all of the related hardware and electrical connections. Failure to perform the commissioning procedure could result in unsatisfactory operation.

Perform the following procedure for the initial start-up and for start-up after major maintenance and/or after repair.

Verify that the connections between the engine's control system and the customer's equipment are connected properly.

Connect Cat ET to the service tool connector. Refer to ""Connecting the Caterpillar Electronic Technician" ".

Set the engine control to the STOP mode. Test each emergency stop button before the engine is started in order to verify that the engine's control system generates an E264 event code.
After the operation of each emergency stop has been verified, set the engine control to the OFF/RESET mode.

Note: Some of the generator's protective devices can only be checked prior to start-up.

Check the generator's protective devices for proper operation.

Turn on the jacket water heater. Verify that the system is set to 45 to 65 °C (113 to 150 °F).
Note: The engine may be difficult to start if the jacket water coolant temperature is below 43 °C (110 °F).
Note: The spark plugs may become fouled with moisture from condensation if the engine is cranked and the jacket water coolant temperature is below 43 °C (110 °F).

Inspect the inlet air system. Make sure that the system does not leak. Make sure that the system is free of debris.

Inspect the fuel supply system. Make sure that the system does not leak. Make sure that the system is free of debris. Blow any debris from the fuel lines.

Connect a properly calibrated emissions analyzer to the exhaust stack.

Perform the daily inspection and all of the daily maintenance procedures that are scheduled in the "Maintenance Interval Schedule" section of the appropriate Operation and Maintenance Manual.

Set the engine control to the STOP mode. Use the "Monitoring System" screen from the "Service" drop-down menu on Cat ET to view the default settings of the trip points for the alarms. Adjust the settings, if necessary.
For the necessary values of the operating parameters, refer to the applicable Data Sheet on engine performance in the engine's Technical Marketing Information (TMI).

Use the "Configuration" screen from the "Service" drop-down menu on Cat ET to view the configuration parameters.

Note: Use the data from the gas analysis and from Caterpillar Software, LEKQ6378, "Methane Number Program" in order to determine the correct settings for the "Fuel Quality" and for the "Gas Specific Gravity" parameters.

View the parameters that are listed in Table 5. Program the parameters, if necessary.

Incorrect programming of the parameters may lead to complaints about performance and/or to engine damage. For descriptions of the parameters, refer to Systems Operation, Testing and Adjusting, RENR2268, "Electronic Control System Parameters".

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Table 5
Configuration Parameters for G3500B Engines
Timing Control
"First Desired Timing"
"Second Desired Timing"
Air/Fuel Ratio Control
"Fuel Quality"
"Gas Specific Gravity"
"Desired Oxygen at Full Load"
"Air/Fuel Proportional Gain"
"Air/Fuel Integral Gain"
Speed Control
"Low Idle Speed"
"Minimum High Idle Speed"
"Maximum High Idle Speed"
"Engine Accel. Rate"
"Desired Speed Input Configuration"
"Governor Type Setting"
"Engine Speed Droop"
"Governor Proportional Gain"
"Governor Integral Gain"
"Governor Derivative Gain"
"Auxiliary Proportional Governor Gain 1"
"Auxiliary Integral Governor Gain 1"
"Auxiliary Derivative Governor Gain 1"
Start/Stop Control
"Driven Equipment Delay Time"
"Crank Terminate Speed"
"Engine Purge Cycle Time"
"Engine Cooldown Duration"
"Cycle Crank Time"
"Engine Overcrank Time"
"Engine Speed Drop Time"
Monitoring and Protection
"High Inlet Air Temp Load Set Point"
Power Monitoring
"Generator Output Power Sensor Scale Factor"
"Generator Output Power Sensor Offset"
"Generator Output Power Sensor Offset"
"Engine Output Power Configuration"
"Engine Driven Accessory Load Configuration"

Calibrate the oxygen sensor. Refer to the applicable Troubleshooting manual for the oxygen sensor's calibration procedure.

Verify that the fuel supply is OFF.

Make sure that the pressure for the electrohydraulic actuator system is sufficient for start-up.
1. Check the oil level in sight gauge (2). Fill the tank to the "FULL" mark on the sight gauge.
1. Remove dust cap (1) and install a pressure gauge to the pressure fitting.
1. To fill the hydraulic hoses and lines, crank the engine and observe the pressure gauge. Do not crank the engine for more than 30 seconds at a time. If necessary, crank the engine repeatedly in order to achieve a pressure of 1380 ± 70 kPa (200 ± 10 psi).
  Note: The ECM will generate event codes and diagnostic codes during this procedure. After the electrohydraulic system is filled with oil, use Cat ET to clear the codes.
1. Stop cranking the engine and check the oil level in sight gauge (2) again. Add oil, if necessary.
  The correct oil level is between the "ADD" and "FULL" marks on the sight gauge.
1. After the electrohydraulic system is primed, crank the engine and verify that the reading on the pressure gauge is 1380 ± 70 kPa (200 ± 10 psi) during cranking.
  This is an adequate pressure for attempting start-up.

Turn ON the fuel supply to the engine. Verify that no gas is leaking. Verify that the gas does not flow past the GSOV.

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Unburned gas in the air inlet and exhaust system may ignite when the engine is started. Personal injury and/or damage may result.

Before starting an engine that may contain unburned gas, purge the unburned gas from the air inlet and exhaust system. Refer to "Unburned Gas - Purge".

Start the engine.
The engine will accelerate to low idle rpm. Operate the engine at low idle. Verify the following conditions:
- Proper engine oil pressure
- No fluid leaks
- No gas leaks
- Proper electrohydraulic oil pressure
Several attempts may be required for the initial start-up before air is purged from the fuel lines.
Note: If the engine will not start, use Cat ET to check for diagnostic codes and for event codes. Correct any active conditions before you attempt to start the engine again.

After the engine is running, test the operation of each emergency stop button.
After each test, reset the emergency stop button and set the engine control to the OFF/RESET mode. Then restart the engine. After all of the emergency stop buttons have been tested, use Cat ET to clear the event codes from the ECM.

Note: Some of the generator's protective devices can only be checked during engine operation.

Check the generator's protective devices for proper operation.

Increase the engine speed to high idle rpm. Verify that the engine is stable.
If the engine is unstable, perform the following procedure.
1. Record the values for these parameters:
  - "Governor Proportional Gain"
  - "Governor Integral Gain"
  - "Governor Derivative Gain"
1. Set the values for the "Governor Proportional Gain", for the "Governor Integral Gain", and for the "Governor Derivative Gain" parameters to zero.
1. Adjust the "Fuel Quality" parameter until the engine becomes stable and the exhaust oxygen is approximately four percent. Verify that the exhaust port temperatures are below the setpoint for a warning.
1. Adjust the primary governor. Refer to ""Adjusting the Governor" ".

Select the "Information" drop-down menu in order to view the status parameters. Review the values of the status groups on Cat ET. Verify that the pumps for the cooling system are operating. Verify that the cooling system temperatures and the cooling system pressures are within the correct operating ranges.

Close the main circuit breaker for the generator in order to engage the generator.
Note: For generator sets that are not connected to a grid, the "Governor Gain" parameters will only be used while the engine is not synchronized and unloaded. For generator sets that are connected to a grid, the "Auxiliary Governor Gain" parameters are used when the generator is connected to the grid. The connection to the grid is indicated when terminal P9-L is connected to terminal P9-C or to terminal P9-O.

Select "Service Procedures" from the "Service" drop-down menu. Select "Air Fuel Ratio Tuning" from the selection menu. Set the "Oxygen Feedback Enabled Status" to "Disabled".
Note: The engine will now operate in open loop mode throughout the entire range of engine loads.

Slowly ramp up to 25 percent load.

Adjust the auxiliary governor.

Slowly ramp up to 50 percent load. Allow the jacket water coolant temperature to reach 75 °C (167 °F).

Verify that the engine is stable.
If the engine is unstable, adjust the auxiliary governor.

Slowly ramp up to 75 percent load.

Verify that the engine is stable.
If the engine is unstable, adjust the auxiliary governor.

Slowly ramp up to 100 percent load.
Note: Watch the "Fuel Valve Position" parameter. This parameter is in status group 9. Watch the "Throttle Position" parameter. This parameter is in status group 7. If either the "Fuel Valve Position" or the "Throttle Position" reaches 80 percent, reduce the load at least 5 percent. Perform the following steps before proceeding to add load.
1. If the "Throttle Position" has reached 80 percent, adjust the wastegate IN in order to decrease the throttle angle.
1. If the "Fuel Valve Position" has reached 100 percent, there is a problem with the fuel supply. Consider the following conditions as potential problems:
  - The Low Heat Value (LHV) of the fuel may be too low. If the LHV is too low, the fuel system will not be able to supply enough fuel for the rating.
  - The fuel pressure to the fuel control valve may be too low.

After any fuel problems have been resolved, continue to ramp up to 100 percent load.

Select "Configuration" from the "Service" drop-down menu. Adjust the "Fuel Quality" parameter in order to obtain the values of emissions that are required at the site.
- To make the air/fuel ratio leaner, increase the "Fuel Quality" parameter.
- To make the air/fuel ratio richer, decrease the "Fuel Quality" parameter.
Use an emissions analyzer in order to verify that the values of emissions meet the requirements of the site.

Increase the engine load to 105 percent load.

Verify that the engine is operating at 105 percent load.

At 105 percent load, adjust the wastegate so that the throttle is wide open. Determine the throttle's position by viewing the "Throttle Position" parameter on Cat ET. The "Throttle Position" parameter should indicate "100".

Reset the load to 100 percent load. The "Throttle Position" parameter should indicate between "65" and "75".

Check the emissions level. If necessary, adjust the "Fuel Quality" parameter. Use the procedure in Test Step 31 in order to obtain the required emissions.

Once the correct emissions are obtained, review the "Actual Oxygen" and "Desired Oxygen" values. These parameters are in status group 9. The engine must still be in the open loop mode.

If the "Actual Oxygen" is higher than the "Desired Oxygen", use the following equation. This equation is used in order to adjust the set point of the "Desired Oxygen at Full Load" parameter:

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Table 6
Equation for the Calculation of a New Set Point for "Desired Oxygen at Full Load"
N = ( A - D ) + C
N is the new "Desired Oxygen at Full Load" value.
A is the "Actual Oxygen" value.
D is the "Desired Oxygen" value.
C is the current "Desired Oxygen at Full Load" value.

If the "Actual Oxygen" is lower than the "Desired Oxygen", use the following equation in order to adjust the set point of the Desired Oxygen at Full Load parameter:

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Table 7
Equation for the Calculation of a New Set Point for "Desired Oxygen at Full Load"
N = C - ( D - A )
N is the new "Desired Oxygen at Full Load" value.
C is the current "Desired Oxygen at Full Load" value.
D is the "Desired Oxygen" value.
A is the "Actual Oxygen"value.

Enter the new "Desired Oxygen at Full Load" value with the Cat ET.

Review status group 9. Ensure that the "Desired Oxygen" and the "Actual Oxygen" parameters are the same value.

Select "Service Procedures" from the "Service" drop-down menu. Select "Air Fuel Ratio Tuning" from the selection menu. Set the "Oxygen Feedback Enabled Status" to "Enabled".
Note: The engine is now operating in closed loop mode.

The engine's operation should not change in closed loop mode. If the engine operation changes, change the "Oxygen Feedback Enabled Status" to "Disabled" and perform the necessary troubleshooting steps.
Note: When the engine is running in closed loop mode, the Fuel Correction Factor (FCF) may no longer be 100 percent. The FCF may adjust in order to compensate for the fuel quality and for the ambient conditions.

Change the engine load to the load that is required at the site. Check the emissions level. Verify that the emissions meet the requirements of the site.

Record the data from all of the status groups on Cat ET. Save the data for future reference.

Initial Start-Up Procedure for Engines that are Equipped with Charge Density

Ensure that all of these factors are in proper condition prior to the initial start-up: engine installation, driven equipment, all of the related hardware and electrical connections. Failure to perform the commissioning procedure could result in unsatisfactory operation.

Perform the following procedure for the initial start-up and for start-up after major maintenance and/or repair.

Verify that the connections between the engine's control system and the customer's equipment are connected properly.

Connect Cat ET to the service tool connector. Refer to ""Connecting Cat ET with the 171-4401 Communication Adapter II " ".

If the information on the generator's output power is provided by a power sensor, check the power sensor's offset voltage. Refer to Troubleshooting, "Generator Output Power Readings Do Not Match". Continue with this procedure after you have minimized the power sensor's offset voltage.

Set the engine control to the STOP mode. Test each emergency stop button before the engine is started in order to verify that the engine's control system generates a E264 event code.
After the operation of each emergency stop has been verified, set the engine control to the OFF/RESET mode.

Note: Some of the generator's protective devices can only be checked prior to start-up.

Check the generator's protective devices for proper operation.

Turn on the jacket water heater. Verify that the heat is set to 45 to 65 °C (113 to 150 °F).
Note: The engine may be difficult to start if the jacket water coolant temperature is below 43 °C (110 °F).
Note: The spark plugs may become fouled with moisture from condensation if the engine is cranked and the jacket water coolant temperature is below 43 °C (110 °F).

Inspect the inlet air system. Make sure that the system does not leak. Make sure that the system is free of debris.

Inspect the fuel supply system. Make sure that the system does not leak. Make sure that the system is free of debris. Blow any debris from the fuel lines.

Connect a properly calibrated emissions analyzer to the exhaust stack.

Perform the daily inspection and all of the daily maintenance procedures that are scheduled in the Operation and Maintenance Manual, SEBU7681, "Maintenance Interval Schedule".

Set the engine control to the STOP mode. Use the "Monitoring System" screen from the "Service" drop-down menu on Cat ET to view the default settings of the trip points for the alarms. Adjust the settings, if necessary.
For the necessary values of the operating parameters, refer to the applicable Data Sheet on engine performance in the engine's Technical Marketing Information (TMI).

Use the "Configuration" screen from the "Service" drop-down menu on Cat ET to view the configuration parameters.

View the parameters that are listed in Table 8. Program the parameters, if necessary.

Incorrect programming of the parameters may lead to complaints about performance and/or to engine damage. For details, refer to Systems Operation, Testing and Adjusting, RENR2268, "Electronic Control System Parameters".

Note: If the generator set is equipped with an EMCP II+ system, it is not necessary to program the "Generator Output Power Sensor Scale Factor" and the "Generator Output Power Sensor Offset" parameters.

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Table 8
Configuration Parameters for G3500C Engines
Timing Control
"First Desired Timing"
"Second Desired Timing"
Air/Fuel Ratio Control
"Fuel Quality"
"Gas Specific Gravity"
"Fuel Specific Heat Ratio"
"Desired Emission Gain Adjustment"
"Air/Fuel Proportional Gain"
"Air/Fuel Integral Gain"
Speed Control
"Low Idle Speed"
"Minimum High Idle Speed"
"Maximum High Idle Speed"
"Engine Accel. Rate"
"Desired Speed Input Configuration"
"Governor Type Setting"
"Engine Speed Droop"
"Governor Proportional Gain"
"Governor Integral Gain"
"Governor Derivative Gain"
"Auxiliary Proportional Governor Gain 1"
"Auxiliary Integral Governor Gain 1"
"Auxiliary Derivative Governor Gain 1"
Start/Stop Control
"Driven Equipment Delay Time"
"Crank Terminate Speed"
"Engine Purge Cycle Time"
"Engine Cooldown Duration"
"Cycle Crank Time"
"Engine Overcrank Time"
"Engine Speed Drop Time"
Monitoring and Protection
"High Inlet Air Temp Load Set Point"
Power Monitoring
"Generator Output Power Sensor Scale Factor"
"Generator Output Power Sensor Offset"
"Engine Output Power Configuration"
"Engine Driven Accessory Load Configuration"

Turn ON the fuel supply to the engine. Verify that no gas is leaking. Verify that the gas does not flow past the GSOV.

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Unburned gas in the air inlet and exhaust system may ignite when the engine is started. Personal injury and/or damage may result.

Before starting an engine that may contain unburned gas, purge the unburned gas from the air inlet and exhaust system. Refer to "Unburned Gas - Purge".

Start the engine.
The engine will accelerate to low idle rpm. Operate the engine at low idle. Verify the following conditions:
- Proper engine oil pressure
- No fluid leaks
- No gas leaks
Several attempts may be required for the initial start-up before air is purged from the fuel lines.
Note: If the engine will not start, use Cat ET to check for diagnostic codes and for event codes. Correct any active conditions before you attempt to start the engine again.

After the engine is running, test the operation of each emergency stop button.
After each test, reset the emergency stop button and set the engine control to the OFF/RESET mode. Then restart the engine. After all of the emergency buttons have been tested, use Cat ET to clear the event codes from the ECM.

Note: Some of the generator's protective devices can only be checked during engine operation.

Check the generator's protective devices for proper operation.

Increase the engine speed to high idle rpm. Verify that the engine is stable.
If the engine is unstable, perform the following procedure.
1. Record the values for these parameters:
  - "Governor Proportional Gain"
  - "Governor Integral Gain"
  - "Governor Derivative Gain"
1. Set the values for the "Governor Proportional Gain", "Governor Integral Gain", and "Governor Derivative Gain" parameters to zero.
1. Adjust the "Fuel Quality" parameter until the engine becomes stable and the exhaust oxygen is approximately four percent. Verify that the exhaust port temperatures are below the setpoint for a warning.
1. Adjust the primary governor. Refer to ""Adjusting the Governor" ".

Select the "Information" drop-down menu in order to view the status parameters. Review the values of the status groups on Cat ET. Verify that the pumps for the cooling system are operating. Verify that the cooling system temperatures and the cooling system pressures are within the correct operating ranges.

Close the main circuit breaker for the generator in order to engage the generator.

Note: When the engine load exceeds 25 percent, the air/fuel ratio control will operate in the feedback mode.

Slowly ramp the load up to 30 percent.
Note: When the air/fuel ratio control is in the feedback mode, the Fuel Correction Factor (FCF) may no longer be 100 percent. The ECM may adjust the FCF in order to compensate for the fuel quality and for the ambient conditions.

Set the "Desired Emission Gain Adjustment" to a value of "100".

Verify that the value of the "Generator Real kW" parameter in Status Group 1 is within one percent of the generator's output power.
If the reading on Cat ET is not within one percent of the generator's output power, refer to Troubleshooting, "Generator Output Power Readings Do Not Match".
When the value of the "Generator Real kW" parameter is within one percent of the generator's output power, continue with this procedure.

Slowly ramp up to 50 percent load. Allow the jacket water coolant temperature to reach 75 °C (167 °F).

Slowly ramp up to 70 percent load. Verify that the engine is stable.
If the engine is unstable, adjust the primary governor.

Verify that the NO_x emissions are above the desired full load setting.

Slowly ramp up to 100 percent load. Verify that the engine is stable.
If the engine is unstable, adjust the primary governor.

Verify that the value of the "Generator Real kW" parameter is within one percent of the generator's output power.

Adjust the "Desired Emission Gain Adjustment" parameter in order to obtain the values of emissions that are required at the site.
- To lean the air/fuel mixture, decrease the gain adjustment.
- To richen the air/fuel mixture, increase the gain adjustment.
A small change in the "Desired Emission Gain Adjustment" causes a large change in the actual exhaust emissions. For example, an adjustment of one percent in the parameter's value will result in a change of 20 to 40 ppm in the actual level of NO_x.
When you adjust the exhaust emissions, make a small change in the value of the gain. Wait until the system stabilizes. Check the emissions again. Repeat the process until the desired emissions level is achieved.
Use the emissions analyzer in order to verify that the values of emissions meet the requirements of the site.

Record the data from all of the status groups on Cat ET. Save the data for future reference.

Adjusting the Governor

The response of the throttle actuator can be adjusted with Cat ET. Use Cat ET to change these three parameters:

Proportional Gain
Integral Gain
Derivative Gain

For details on these parameters, refer to Systems Operation/Testing and Adjusting, "Electronic Control System Parameters".

The default values should be sufficient for initial start-up. However, the values may not provide optimum performance.

These adjustments are provided in order to obtain optimum responses to changes in the engine's load and in the engine's speed. The adjustments also provide stability during steady state operation.

If you have a problem with instability, always investigate other causes before you adjust the governor. For example, diagnostic codes and unstable gas pressure can cause instability.

When you adjust the primary governor, make sure that the "Grid Status" parameter is "Off". When you adjust the auxiliary governor, make sure that the "Grid Status" parameter is "On".

To change the proportional gain, the integral gain, or the derivative gain, use the "Real Time Graphing" feature on the "Information" drop-down menu of Cat ET. The graph provides the best method for observing the effects of your adjustments.

After you make adjustments, always test the stability by interrupting the engine speed and/or load. Operate the engine through the entire range of speeds and of loads in order to ensure stability.

Note: Adjustment of the proportional gain directly affects the speed of the throttle actuator when there is a difference between the actual engine speed and the desired engine speed. An excessive increase of the proportional gain may amplify instability.

To set the proportional gain, increase the proportional gain until the actuator becomes unstable. Slowly reduce the proportional gain in order to stabilize the actuator. Observe that the engine operates properly with little overshoot or undershoot.

The adjustment of integral gain dampens the actuator's response to changes in load and in speed. Increasing the integral gain provides less damping. Decreasing the integral gain provides more damping. To reduce overshoot, decrease the integral gain. To reduce undershoot, increase the integral gain.

Note: An increase of the integral gain may require a decrease of the proportional gain in order to maintain engine stability.

Illustration 13 shows some typical curves for transient responses.

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Illustration 13	g01017530
Typical curves for transient responses (Y) Engine speed (X) Time (1) The proportional gain is too high and the integral gain is too low. There is a large overshoot on start-up and there are secondary overshoots on transient loads. (2) The proportional gain is slightly high and the integral gain is slightly low. There is a slight overshoot on start-up but the response to transient loads is optimum. (3) The proportional gain is slightly low and the integral gain is slightly high. There is optimum performance on start-up but slow response for transient loads. (4) The proportional gain is too low and the integral gain is too high. The response for transient loads is too slow. (5) The response to transient loads is adjusted for optimum performance.

Decrease the derivative gain until a slow, periodic instability is observed. Then, slightly increase the derivative gain. Repeat the adjustments of the proportional gain and of the integral gain. Continue to increase the derivative gain and readjust the proportional gain and the integral gain until stability is achieved and the engine's response to changes in load and in speed is optimized.

Illustration 14 is a graphic representation of adjusting the derivative gain.

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Illustration 14	g01017541
The increased width of the line for the actuator voltage indicates that the throttle actuator is more active as the derivative gain increases. (Y) Actuator voltage (X) Time in seconds

Unburned Gas − Purge

The following events cause unburned gas to remain in the air inlet and in the exhaust manifold:

Emergency stop
Engine overspeed
The engine control is set to the STOP mode and the gas shutoff valve does not close.
Unsuccessful successive attempts to start the engine

Unburned gas may remain in the air inlet and exhaust system after several unsuccessful attempts to start the engine. The unburned gas may increase to a concentration that may ignite during a successive attempt to start the engine.

Perform the following procedure in order to purge the unburned gas:

Connect Cat ET to the engine.

Verify that the value of the "Engine Purge Cycle" parameter is equal to ten seconds less than the value of the "Crank Cycle" parameter.

Set the engine control to the START mode. The engine will crank for the "Engine Purge Cycle" time. Then, the gas shutoff valve will be energized and the ignition will be enabled. The engine will start.