Initial Setup for Certified G3512 Generator Set Engines {1021} Caterpillar

Engine

G3512 (S/N: E2P1-UP; E2S1-UP; E2X1-UP)

Introduction

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

The engine setup instructions that follow are intended to maintain emissions for pipeline natural gas with a Lower Heating Value (LHV) of 800 to 1000 BTU/ft3. The engine control strategy is not designed to run on any fuels outside of this range. Maintenance of emissions is not guaranteed on engines that are run on fuels outside of this range.

Set the Natural Gas Fuel Supply Pressure

The regulator should be sized so that the supply pressure to the tecjet fuel valve is between 0.5 psig minimum at rated load and 5 psig maximum at idle. The regulator must be able to provide constant pressure to the tecjet from cranking speed to full load.

Initial Set-Up Procedure

Ensure that all these factors are in proper working condition prior to the initial start-up: engine installation, driven equipment, all 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.

Note: Use Cat^® Electronic Technician (ET) version 2016A v1.0 or later.

1. Current fuel analysis

   Obtain a fuel analysis for natural gas fuel quality supplied to the engine. The following parameters are required to input into Cat ET:

   • Gas Lower Heating Value (LHV)

   • Gas specific gravity

   • Gas specific Heat Ratio
   Show/hide table

   Illustration 1	g06090017
   Engine load factor equation

2. Update engine load factor parameters in Cat ET.

   Note: The following parameters impact the engine software load factor calculation, which uses the equation shown above.

   The accuracy of these parameters will impact the performance and emissions of the engine.

   1. Engine driven accessory load.

      The total accessory load at 1800 rpm must be input into Cat ET. This accessory load includes a package mounted-radiator and alternator (if applicable). Use the following guidance for load:

      Package Mounted Radiator: 37 kW (50 hp)

      Alternator: 1 kW (1.4 hp)

      If the generator set is not using a package-mounted radiator or alternator, this value must be set to 0 kW (0 hp).

   2. Generator efficiency configuration.

      Input expected generator efficiency into ET. This efficiency is based on power factor and maximum electric load that the generator set is able to achieve at operating site.

3. Calibrate the NO_x sensor.

   The NOx sensor must be calibrated at initial engine setup, with changes in fuel quality on site, and whenever the sensor is replaced. A calibration procedure is available in Cat ET. This procedure adjusts the slope of the sensor to account for this drift. During the calibration, the concentration of NOx that is reported by Cat ET is compared to the actual concentration that is reported whereas the exhaust is analyzed by an emissions analyzer.

   Note: Make small changes to the slope value during the calibration procedure. If large changes are made to the slope value, the engine operation may become unstable. Allow engine to stabilize after each adjustment is made.

   A 391-8170 EMISSIONS ANALYZER TOOL GP (Bluetooth Module) or a 393-0673 EMISSIONS ANALYZER TOOL GP can be used during the calibration procedure. Before a calibration of the NOx sensor is performed, obtain a recent gas analysis of the fuel to confirm the settings of the engine fuel quality and specific gravity. If necessary, update the configurable parameters in Cat ET. Refer to Initial Set-Up Procedure for CAT ET for more details. Calibration must be done during controlled engine operating conditions. The engine must be running and the operating conditions of the engine must be stabilized. Ensure that the requirements that are displayed on Cat ET are satisfied prior to initiating the calibration. If these conditions are not maintained during the entire calibration procedure, the calibration will be aborted.

   1. Start the engine, allow the engine to warm to normal operating temperature.

   2. Connect a 391-8170 EMISSIONS ANALYZER TOOL GP (Bluetooth Module) or a 393-0673 EMISSIONS ANALYZER TOOL GP to the engine exhaust system. Allow the NOX readings from the analyzer to stabilize.

   3. Connect Cat ET to the service tool connector. Establish communications with the ECM.

   4. Access the "Service/Calibrations/Engine Exhaust NOx Level Sensor Calibration" screen of Cat ET. Use Cat ET to start the calibration.

   5. Follow the prompts to guide you through the calibration procedure. Be sure to allow the engine to stabilize before each measurement is taken.

   6. Compare the value of the NOx that is reported from Cat ET to the value of NOx that is reported from the exhaust analyzer. Select the arrow buttons at the bottom of the calibration screen to increase or decrease the sensor slope value that is reported by Cat ET.

      Note: Make small changes to the slope value during the calibration procedure. If large changes are made to the slope value, the engine operation may become unstable. Allow the engine to stabilize after each adjustment is made. When the values are comparable within +/-10 ppm, click the "Next" button at the bottom of the screen.

   7. Cat ET will prompt you to allow the engine to stabilize for 3 minutes to verify the correct settings.

   8. If necessary, perform the calibration procedure again to recalibrate the sensor.

   9. The NOx feedback should be automatically enabled once the NOx calibration has been completed

4. Exhaust bypass valve setting procedure using turbocharger compressor bypass actuator position.

   Note: The exhaust bypass valve must be set at 100% load factor as indicated in Cat ET. If 100% load factor cannot be achieved on site due to site conditions, the exhaust bypass valve must be set at the maximum allowable load factor for the site.

   Note: The compressor bypass actuator position will decrease with an increase in temperature for a given load and altitude. The exhaust bypass valve must be set to give enough compressor bypass margin if stable operation at higher ambient temperatures is desired.

   1. Determine current inlet air temperature for the site.

   2. Determine the maximum inlet air temperature for the site.

   3. Reference the table below to determine proper compressor bypass actuator position at 100% load factor. Adjust the exhaust bypass valve to attain the proper compressor bypass position.
      Show/hide table

      Illustration 2	g06143810

   4. If 100% load factor cannot be achieved on site due to site conditions, set the exhaust bypass valve at the maximum allowable load factor for the site conditions.

   5. If the maximum allowable load factor falls between 100% and 75%, reference the proper table below for target compressor bypass position at 75% for either 1000ekW or 750ekW EPA Certified ratings. You may have to interpolate to obtain the target compressor bypass position.
      Show/hide table

      Illustration 3	g06143811

      Show/hide table

      Illustration 4	g06143813

   6. If the maximum allowable load factor for the site falls below 75%, the exhaust bypass valve will remain closed. Adjust the exhaust bypass valve all the way to its lowest setting.

5. Check Fuel Correction Factor (FCF)

   • The FCF needs to be at 100 percent ± 5 percent above 50 percent load. Adjust the fuel quality value (BTU) only if the FCF is outside the ± 5% range.

   • The fuel quality value can only be changed between 800 to 1000 BTU/ft3 in Cat ET.

   If not within specifications, return to Step 3.

6. Check Emissions

   Note: Desired NOx level has been disabled in Cat ET. For emissions compliance, the desired NOx level has been hard-coded to 240 ppm in the engine software

   By using ET, monitor the NO_x PPM. The NO_x PPM screen will display the value shown on the analyzer (±10 PPM) for a 5 minute period. If not, return to step 3.

Generator Set Fast Start Setup

This generator set has been designed to be compatible with an NFPA110 Type 10 capable system. The following parameters need to be considered to ensure optimum start times and proper engine protection upon a failed start attempt.

1. Crank Terminate Speed setting in Cat ET.

   The crank terminate speed setting impacts the handoff between the auxiliary fuel valve and the main fuel valve (tecjet). Setting the value too high could result in a richer than desired fuel-air mixture, which would increase the start time and potentially cause the engine to shutdown. Setting the value too low could result in a leaner than desired fuel-air mixture, which would result in excessive start times.

   The crank terminate speed setting has been set to a default value of 500 rpm. Depending on the site conditions, this setting may need to be adjusted to optimize start time. The full adjustable range is 150 rpm to 700 rpm. Follow the procedure below to optimize the crank terminate speed setting:

   1. With the default value of 500 rpm, record engine speed in Cat ET during a start-up to 1800 rpm.

   2. If the speed trace shows the speed acceleration rate decrease or flatten at crank terminate speed, the crank terminate speed is set too low. Increase the value by 50 to 100 rpm and conduct another start-up.

   3. If the speed trace shows the engine speed decrease after crank terminate speed, the crank terminate speed is set too high. Decrease the value by 50 to 100 rpm and conduct another start-up.

   4. Repeat steps a thru c until an optimum speed acceleration is observed with minimum speed stall time at crank terminate.

2. Engine Purge Cycle Time setting in Cat ET

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

   • Insufficient rpm drop time to purge the engine following an engine shutdown

   Unburned gas may remain in the air inlet and exhaust systems and may ignite during an attempt to start the engine if any of the events above occurred during the previous engine shutdown.

   To protect the engine, the engine software will force a purge during the next start attempt. This purge time can be set in Cat ET. The default value is set to 7 seconds. The full adjustable range is 7 seconds to 25 seconds.

   Note: The purge cycle is inactive during the first start-up attempt to minimize start time, assuming the events above were not tripped during the previous shutdown event.

Note: The following procedure will not work if the engine control does not control the GSOV.

1. Connect Cat ET to the engine.

2. Adjust that the value of "Engine Purge Cycle" parameter to 10 seconds and the "Crank Cycle" parameter to 20 seconds.

3. Set the engine control to the "Start" mode. The engine will crank for the "Engine Purge Cycle" period. The GSOV will be energized and the ignition will be enabled. The engine will start.

4. Continue with the previous procedure being performed.

Engine Pre-lubrication Settings for the EPA Certified Arrangement

The"Engine Pre-Lube" configuration can be switched between either "Enabled" or "Disabled".

The system is only available in "Continuous" mode with adjustable settings for the duration and the interval.