Mechanical Interface Option
Control Lines for Mechanical Pumps/Dispensers
Page 36
MDE-4319A TopKAT Fuel Managment System Installation Manual · November 2005
Control Lines for Mechanical Pumps/Dispensers
Descriptions of the control lines are provided to familiarize the installer with the control inputs
and outputs that are used to control a mechanical pump/dispenser. Reading these descriptions
will give the installer a better working knowledge of the system and aid in planning the site
wiring.
Grounding
To ensure proper operation of the equipment and provide the necessary safety factors, this unit
must be grounded. A ground wire (preferably green) must be connected between the ground
wire of the system and the main electrical service panel. One (1) earth ground connection is
required per unit. A ground rod must be installed at the main electrical panel in accordance
with the National Electrical Code. This ground rod is to be a solid, corrosion-resistant
conductor. It should be properly tied into the ground bus strip of the panel. We recommend
the neutral and ground bus strips be bonded together (unless prohibited by local codes).
Reset Motor Feed
This is a 115 VAC input which is supplied through the pump handle switch to activate the reset
motor. This line should be switched through the TopKAT and should only be on when the
pump/dispenser is authorized or in manual mode. Without power supplied to this line, the
pump/dispenser will not reset when the pump handle is turned on. Two feed lines are provided
for twins. This feed is also connected to the input of one of the internal switches of the electric
reset. When the reset finishes its cycle, the 115 VAC input to the switch will be passed
through as an output causing the solenoid valve (optional in some models) to open and the
reset complete line to indicate 115 VAC.
Pump Motor Feed
This is a 115 VAC input which is supplied to the input side of one of the internal switches of
the electric reset. This line should be switched through the TopKAT and should only be on
when the pump/dispenser is authorized or in manual mode. When the reset finishes its cycle,
the 115 VAC input to the switch is passed through as an output causing the pump motor to
receive power and begin fueling. Without power to this line, the unit would reset, but be
unable to fuel. Two feed lines are provided in twins which contain two motors. The gauge of
this wire (and its neutral wire) should be determined according to the size of the motor, the
voltage at which the motor will be powered (115 VAC or 230 VAC), and the distance from the
breaker panel to the pump. It is possible to combine the pump motor feeds for twins and
supply them from one breaker; however, the gauge of the wire needs to be adjusted to handle
the load of two motors.
Note: 230 VAC is developed across a motor when the other leg of the motor is connected to a
Phase 2 Feed.
Neutral Feed
This is the AC current return line back to the breaker panel for all attached devices (pump
motor, reset motor, solenoid valves). The gauge of this wire must be equal to that of the pump
motor feed (suction pumps) or submersible feed (dispensers).
