Prins VSI-CNG System
VSI is an abbreviation for "Vapour Sequential Injection". The VSI-CNG system is the most advanced CNG system available on the market. With the VSI-CNG system PRINS strives for optimal emission and cost reduction.
The VSI-CNG system is developed in close cooperation with Keihin Corp. of Japan, one of the world’s leading injector manufacturers and a name that stands for OEM quality and reliability.
The VSI-CNG system is fully integrated by way of a "master - slave" method with the vehicle ECU, making it (E)OBD compatible, therefore signal emulation is not required.
The key components of the system are all of OEM quality and specially designed for CNG applications. All components comply with the strictest regulations and certifications, therefore the system and its components are R110 and ISO 15500 homologated. The installation of the components is very easy due to the compact design of the components.
The specially dedicated diagnostic software is unique and enables fine tuning the VSI-CNG system for optimal emission reduction. By means of the specially developed Prins Timing Optimizer (PTO) it is possible to decrease the power loss to a minimum.
CNG Pressure Regulator
• Precision built ‘Single Stage’ regulator developed by KEIHIN in cooperation with PRINS
• Based on OEM technology, quality and standards
• Integrated relief valve
• Small pressure drop level equivalent to a two stage regulator
• Manifold reference function
• System pressure is not affected by tank pressure
• Performance at cold temperature is identical as at normal temperature
• Optional in-line electrical lock-off valve. Wide range of connections possible at the valve inlet
Keihin Injectors
Injects LPG/CNG into the inlet manifold for each cylinder. Developed by Keihin Corp, Japan, one of the world’s leading injector manufacturers, in cooperation with Prins. Injectors are of OEM quality and reliability.
Injectors
• OEM quality injector.
• Lifespan at least 290.000.000 cycles or 240.000 km -> 2 year unlimited warranty!
• Excellent linear flow range (linear 2% accuracy form min to max flow). Linear flow starting from 2,5 msec.
• Low-resistance 1,25 Ω.
• 5 injector sizes for engine capacities from 9 kW till 45 kW each cylinder. (e.g. 3 cyl with 27 kW to 10 cyl. 450 kW).
ECU - Electronic Control Unit
The ECU controls the VSI system.
• Approval for E-marking LPG R67-01 and CNG R110 regulations
• 3 versions: 4, 8 and 10 cylinder
• All upgrades are downwards compatible
• High reliable
• Measuring the engine signals, petrol-injectors, rpm, MAP, coolant, etc.
• Controlling the solenoids
• Controlling the injectors
• Cut off the petrol-injectors
• Read out fuel choice
• Communication with the diagnostics program
• ECU injector driver capability up to 10 cylinders
• Injector drivers based on “closed loop peak & hold current control”
• Constant monitoring of the injector diagnostics:
- Overload
- Driver temperature
- Short circuit
- No load
• Software for diagnostics, service and parameter load operates with Windows 98, 2000, XP and Vista
• CAN-controller (2.0b) enables communication with OEM CAN-bus
• Complete wiring harness: colour coded, with text and numbers for simple and efficient installation
Fuel Switch
The fuel switch used by the VSI-system controls the following functions:
• Fuel choice.
• Monitoring the fuel level.
• Reporting errors.
The fuel switch is operated by a touch key to switch from petrol to LPG and vice-versa. The fuel switch is also equipped with LED indicators to monitor the level of the fuel in the tank. When the LPG level is too low the reserve LED lights up. When there is an automatic switch-over to petrol because the LPG tank is empty, the driver is being warned by a buzzer signal and a flashing LED indicator.