The Technology
SEQUIN™ LPG Dual Fuel Sequential Injection System
SEQUIN is an engine enhancement system that, when installed, allows the engine to seamlessly operate on propane as well as gasoline, without ANY performance disadvantages.
Description of the Technology
- SEQUIN is a dual fuel technology:
- SEQUIN is installed on the vehicle COMPLEMENTARY to the native gasoline system.
- SEQUIN leverages the Original Equipment Manufacturer’s engineering.
- A SEQUIN equipped vehicle does not disconnect any component of the original gasoline system.
- Safety Certification:
- SEQUIN utilizes certified components purchased from 3rd parties or manufactures components that are then certified by CSA as fit for use.
- SEQUIN is a Complete Package:
- SEQUIN technology is shipped for install as a complete package for a specific vehicle platform, including tank, under-hood components, fasteners, and all accessories required for installation:
- Helps to ensure the conversion utilizes all approved components.
- Helps to ensure that the conversion is compliant with applicable legislative requirements and regulations.
Application of the Technology
- SEQUIN technology is specifically packaged, programmed and certified for specific vehicle platforms.
- The targeted vehicle platforms are those typically utilized by fleets incurring high mileage.
Operating Principles
- SEQUIN is tested to ensure compliance with OBDII as part of the US EPA Certification process.
- The OEM engine management system controls the operation of the engine on propane. SEQUIN merely provides supplementary electronic assistance and control functionality to the OEM computer.
- All OEM engine and emission control technology remains fully functional. Nothing is disconnected.
Vehicle Operation
- Starting:
- The vehicle will start every time on gasoline.
- The vehicle is immediately ready for operation after starting, regardless of whether it is operating on gasoline or propane.
- Switching from Gasoline to Propane:
- After the vehicle starts on gasoline, the SEQUIN computer monitors for conditions such as propane vapour pressure and engine temperature. When conditions are appropriate, the engine automatically substitutes propane for gasoline.
- This switch occurs without operator involvement or knowledge, and can vary from 20 seconds to 6 minutes depending upon various factors such as vehicle operating temperature and propane temperature. During the time before switching to propane, the vehicle can be operated normally, as there is no requirement to wait for the changeover to propane.
- Should the operator inadvertently run out of propane, the vehicle immediately switches to gasoline operation, without any involvement of the driver and without any detrimental impact to vehicle performance.
- Performance:
- “Performance on Gasoline” is the benchmark.
- There are no performance disadvantages to operating on the SEQUIN technology.
Primary Subsystems
- Propane Storage:
- Tanks have been specifically engineered for use with the SEQUIN technology.
- Tank configurations can be manufactured to suit the particular requirement if standard configurations are not suitable.
- Vapour Production:
- Liquid Propane Pump:
- CSA approved external pump and housing circulates liquid propane through a heat exchanger and back to the tank.
- The pump cycles on and off as required to maintain tank vapour pressure by ensuring the liquid propane in the tank maintains an appropriate temperature.
- Heat Exchange Unit:
- CSA Approved heat exchanger transmits heat from engine coolant into the liquid propane that is then returned to the tank.
- Tank Pressure Sensor:
- Monitors tank vapour pressure, switching the pump on and off as required to circulate liquid propane through the heat exchanger.
- Vapour Injection:
- Sequential Injection Module (SIM):
- One small computer module encased in an aluminum box and waterproofed.
- The electronic “brain” of the technology that handles all communication with the OEM engine management system.
- Wiring Harness:
- Specifically designed to facilitate the interface of the SIM to the OEM engine management system and to the propane injectors.
- Pressure Regulator:
- Reduces tank pressure to the operating pressure required by the injectors.
- BOSCH gaseous fuel injectors:
- Operates sequentially, timed to each cylinder’s intake cycle.
- Wired to the SIM and controlled by the OEM computer’s instructions.
- Braided Steel Injector Lines:
- CSA Approved as fit for purpose.
- Deliver propane into the intake manifold.
- Check valves at the intake manifold eliminate lag time between injector opening and fuel delivery.
Installation
- Installation takes between 12 and 16 hours depending upon the experience of the installer.
- Assuming the installer has some propane experience, training can be accomplished in 1 to 2 days.
- Depending upon fleet specific requirements, installation can be arranged by SFI, done by the fleet operator, or completed at a designated facility of choice.
- SFI would be pleased to discuss this issue with you to ensure the correct arrangement is in place to meet the needs of your specific situation.
Maintenance
- There are no special gauges or equipment needed to maintain SEQUIN.
- Standard engine diagnostic equipment will provide the technician with all of the information required to service the vehicle, including the SEQUIN equipment.
- Normal OEM Maintenance schedules should be followed.
- As there are few moving parts, maintenance is not a significant burden.
London Police Service SEQUIN™ Testimonial
from Propane Canada Magazine
September - October 2004
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