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Gas System Main Parts Technical and Installation Requirements

by Starlight Generator dieselgeneratortech

2.2 Gas system main parts technical & installation requirements

1. Pressure reducer

1.Inlet pressure: 3-7bar;

2. Outlet pressure: 1-2 kbar;

3. Flow:40-50 N/h

Installation requirements

● Pressure reducer is a supplied accessory and shall be mounted in places with little vibration and near to the engine with distance not exceeding 2m.

● It shall be installed behind the filter and installation position shall be convenient for regular adjustment, inspection and maintenance of pressure reducer.

● Pipeline connecting to pressure reducer shall be reasonably arranged and free from interference.

●Pressure reducer gas outlet and the bottom shall not be upward to prevent fuel gas greasy dirt from back flowing into pressure reducer.

●Screw off the top cap and adjust the screw to pressure reducer valve, turn clockwise to thicken and anticlockwise to thin (Note: such mode of regulation is only applicable to high speed regulation).

2. Low pressure gas filter

Technical parameters:

1.Maximum working pressure: 2bar;

2. Working temperature: -15℃～60℃;

3. Filter radius≤50μm.

Installation requirements:

●Gas filter installation position must be convenient for repair, cleaning and replacement;

●Within filter service life, pressure drop shall be less than 20kPa to guarantee system performance.

● Pay attention to arrow pointed airflow direction during installation

3. Mixer

Technical parameters:

1. Fuel type: natural gas, LPG, methane

2. Inlet pressure: -0.37kPa

3.Working temperature: —40℃~121℃

Installation requirements and operating instructions:

●Vertical installation

●Pay attention to arrow pointed airflow direction during installation

4. Wiring harness

Installation requirements:

●Wiring harness is not allowed to be laid at exhaust pipe side to avoid high temperature damage.

Wiring harness is more than 150mm away from exhaust pipe and vortex end of turbocharger;

●Wiring harness shall be fixed reliably to prevent interference or friction with sharp matters. If not, please take protective measures.

●Wiring harness shall be free from intertwining and overlapping and reasonably aligned, convenient for later maintenance.

Air

inlet

Gas

inlet

Mixture outlet

Operation & Maintenance Manual for WP13NG Series Gas Generators

Green Power International Weichai 9

5. Engine control unit (ECU)

ECU collects inlet manifold pressure (MAP), inlet manifold temperature (MAT), engine phase, revolving speed, outlet water temperature, exhaust oxygen concentration and other signals and controls the action of electronic throttle, ignition timing and ignition orders after calculation so as to accomplish electronic control of engine.

Engine control unit (ECU) shall be installed in control panel to realize real-time monitoring of engine parameters.

Technical parameters:

● Working voltage:12V;

● Working environment: -20℃～100℃;

6. Inlet temperature, pressure sensor (T/MAP)

T/MAP sensor integrates pressure and temperature measurement. Engine control unit (ECU) uses sensor signals to calculate engine’s mixture air input.

Technical parameters:

1.Applicable pressure: 20～250KPa

2.Applicable temperature: -40℃～125℃

3.Voltage: 4.5V～5.5V;

7. Revolving speed sensor

Revolving speed sensor is mainly used to measure engine’s revolving

Technical parameters:

1.Normal working temperature: -40℃～120℃

2.All magnetic field allowable: ≤2KA/m

3.Maximum torque allowable shall be 8N·m during

assembly; installation gap shall be 1.5-2 mm;

4.Thread specification: M18×1.5mm

8. Water temperature sensor

Water temperature sensor is mainly used to measure cooling water temperature. ECU may regulate idle speed and ignition advance angle in different water temperatures according to ECU stored data.

Technical parameters:

1.Rated working voltage: 5±0.15V

2.Temperature measuring range: -40℃～﹢140℃

3. Normal working temperature of connectors: -40℃～

+130℃

9. Oxygen sensor (UEGO)

Oxygen sensor is used to measure oxygen concentration in exhaust gas and transfer it into electrical signal for the use of ECU so as to monitor engine’s air-fuel ratio.

Installation requirements

●Installation position of oxygen sensor plays an important part in system’s work accuracy, so it must be installed strictly in accordance with specific requirements.

●It shall be installed 3～5 times of exhaust pipe diameter away from downstream of turbocharger outlet or exhaust elbow;

●It cannot be installed on exhaust elbow;

●In order to prevent oxygen sensor from being burned on exhaust pipe and for the convenience of disassembly, thread shall be smeared with anti-burning glue during the installation of oxygen sensor;

●Oxygen sensor wiring harness and connectors shall be kept away from exhaust pipe to avoid caking;

●Height of oxygen sensor screw seat welded on exhaust pipe shall be less than 10mm and length of oxygen probe in exhaust pipe shall not be less than 13mm;

●Large gas consumption and unstable revolving speed occur when sensor is in failure or wiring hardness and connector is in bad contact;

●Oxygen sensor shall be installed on the exhaust pipe (circumferential), facing away from the engine;

●Oxygen sensor satisfying above mentioned conditions shall be close to turbocharger.

10. Revolving speed sensor

Revolving speed sensor is mainly used to measure engine’s revolving speed. Engine control unit (ECU) uses revolving speed to control many parameters, including air input, amount of fuel, ignition advance angle, etc. Control requirements of these parameters request the engine control unit (ECU) to know engine’s camshaft position (for example which cylinder is ignited) and revolving speed.

Technical parameters:

1.Normal working temperature: measuring terminal: -40℃～150℃; plugging terminal: -40℃～

120℃;

2. All magnetic field allowable: ≤2KA/m

3. Maximum torque allowable shall be 8N·m during assemble (when 8.8 M6X12 bolts are used), installation gap shall be 0.5~1.5mm.

11. Electronic throttle

Electronic throttle is mainly used for controlling mixture flow, engine idling and maximum revolving speed. ECU uses 1600Hz PWM signal to control the action of throttle and its working stroke is limited to 10％～90％ (opening of butterfly valve ) by ECU.

Failure of electronic throttle or bad contact of connectors will lead to: unstable revolving speed, unable to start, inhibited acceleration, unable to acceleration and other failures. Use multi-meter to check contact status of connectors; in case that connectors and wiring harness have no problems, and its feedback signal bounces, replacement of new parts shall be taken into consideration.

Installation requirements

●Electronic throttle shall be installed in low-temperature environment.

12. Ignition coil

This system adopts independent cylinder ignition coil, ECU controls coil’s charging hours, charging time and discharging hours and engine charge current shall be maintained at 6.5A under any conditions.

Installation requirements:

● Ignition coil wiring harness shall be free from stresses;

●Use multimeter to check the contact situation of wiring harness and connectors;

●Ignition coil shall be kept away from engine metal rack to prevent breakdown of sparking

13. High-voltage line

High-voltage line is used to transmit high pressure spot generated by ignition coil to sparking plug so as to generate electric spark for ignition of combustible mixture

Installation requirements:

●High-voltage line assembly insertion pressure is not greater than 80N, and withdrawal force shall be 30～ 70N；

14. Sparking plug

Sparking plug is used to receive high voltage generated by ignition coil, generate electric spark and ignite flammable gas. This engine uses double-platinum sparking plug.

Installation requirements

●Installation torque of sparking plug: 20～25 N·m

●Sparkling plug gap: 0.35＋0.05mm (regulate with plug gauge)

15. Debugger (optional)

As an ECU Ancillary product, handheld debugger is mainly used for replacing supervisory computer to carry out data alignment and parameter calibration upon ECU to make it in optimum status, thereby to get rid of complicated ECU debugging works. It is easy for debugging personnel to understand and adjust various ECU parameters.

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