Part No. 920525 Rev A - Wayne 3/VISTA series Service Manual

The operation for all 3/Vista series dispensers is similar , except where distinguished below between
lift-to-start and push-to-start models.
Before the dispenser will reset unit prices must be set and an authorization signal must be received,
and if a blender model, blend ratios must be set. The unit prices, authorization, and blend ratios can
be manually set at the dispenser for stand-alone operation, or from a control system, after first setting
the fueling point ID.
The above requirements are discussed in detail in this section. Once they have been satisfied, the
dispenser operates as described in the following sections.
2.1. LIFT-TO-START MODELS
• When the nozzle is removed from the nozzle boot and the lever is lifted, the constant +5
VDC that the computer supplies to the nozzle switch goes to ground. This signals the
computer to begin its reset cycle.
• When the dispenser receives an Authorization signal either from the control system or,
if stand-alone, from the dispenser, the correct submersible pump relay will be energized.
• The computer performs a self test and flashes eights, blanks, then resets to zeros, on the
main sale display.
• After the dispenser resets, the proportional flow control valve (or valves if a blender
model) is energized with just enough current to barely open the valve and allow a slow
flow.
After a small amount of fuel has been dispensed, the valve is energized with enough
current to be in the fully open position and allow fast flow. During the sale, the valve will
be continuously controlled with the proper amount of current to limit fuel flow rate to a
maximum of 10 GPM
• In preset sales, the current received by the proportional flow control valve(s) is
reduced to the barely open position just prior to the final shut-off amount. The valve(s)
is then de-energized when the final amount is reached.
• When the lever is lowered, the nozzle switch goes back to the constant +5 VDC, the sale
is complete, and the nozzle is returned to the nozzle boot.
2.2. PUSH-TO-START MODELS
• When the nozzle is removed from the nozzle boot, the constant +5 VDC that the
computer supplies to the nozzle switch goes to ground. At this point, one of the lighted
buttons (grade select, cash/credit, or push-to-start, depending model) will flash indi-
cating that one of the buttons must be pressed.
• When one of the lighted buttons is pressed the constant +5 VDC that is supplied to the
switch goes to ground. This signals the computer to begin its reset cycle.
• When the dispenser receives an Authorization signal either from the control system or
from the Authorize switch in the dispenser, the correct submersible pump relay will be
energized.
* The maximum allowable flow rate in the United States is 10 gallons per minute.
June 2001
2. OPERATION
*
, and if a blender model, provide the correct blend ratio.
3

Part No. 920525 Rev A