Wayne GLOBAL VISTA CNG, Инструкция по эксплуатации

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© Copyright
2008-03-20 V0 Rev.01.0
- 19 - WT004139
Three-way valve
The three-way valve is a ball valve which allows gas to flow from the CNG to the vehicle tank.
This valve works according to three different positions:
•
OFF position prevents gas flow (no dispensing);
•
ON position allows gas flow (dispensing);
•
VENT position allows gas to vent from the nozzle;
When the three-way valve is in the vent position, the nozzle can be removed from the CNG vehicle in total
safety.
The three-way valve can be integrated on the connector (standard NGV1 and NGV2).
It is important to place the three-way valve in the vent position before connecting the nozzle to
the tank
Breakaway Device
The CNG dispenser is equipped with breakaway devices capable of immediately interrupting the gas flow if a
vehicle that is being fuelled should move with the nozzle still connected to the tank.
This safety device interrupt gas flow and hence prevents damages to persons, the dispenser and the vehicle.
ELECTRICAL COMPONENTS
Electronic head
Description
The CNG dispenser is equipped with a Dresser electronic head which guarantees high performance in
calculating and constantly monitoring all the operations carried out by the dispenser.
The head, designed specifically to manage CNG dispensers, performs the following operations:
•
management and control of the valves and sensors in the dispenser (meters, transducers, etc);
•
calculation and display of fuel-related prices and weights;
•
management of devices indicating the status of the dispenser (signal lights);
•
interfacing with any POS System;
Operation
After having received the signals/values from the mass-flow meter (or any other sensors) the head performs
the following operations:
•
controls the CNG fuelling procedure;
•
shows fuelling data on the LCD displays;
The electronic head, used on different types of CNG dispensers, can work in four different modes:
•
single level mode;
•
multi level mode (cascade system);
The data displayed is:
•
total price;
•
volume supplied, displayed in «kg» or «m
3
» according to the chosen configuration;
•
unit price;