Syn-Tech Systems FuelMaster FMU-2500 Classic Installation Manual page 97

switch detection.
The +12V and 0V positions are not tied to a specific P_ position. Any +12V or 0V position may
be used with any P_ position. Since there is only one 0V position for every two P_ positions, two
conductors must be connected to each 0V position when 0V connections are required.
See Figures 4-18 through 4-25 for pulser connection diagrams. Typical connections to
mechanical pulsers are with two or three conductors. All mechanical pulsers will require a 12
VDC input to return a 12 VDC pulse for the FMU. Many will also require a third conductor
connection to 0V ground, or common.
Some open collector pulse generators such as the Gasboy Pump I/F Board cannot accept a direct 12
VDC input. Applying 12 VDC directly to the Pump I/F Board will damage it.
Certains générateurs d'impulsions collecteur ouvert comme la pompe, je Gasboy Conseil / F n'acceptera
pas une entrée 12 VDC directe. Application 12 VDC directement à la pompe, je / F Conseil sera
l'endommager.
Some pulse generators are open collector. They require a power input on the pulse return line
before a pulse may be generated. Open collector pulsers will also require a pull-up resistor. The
pull-up resistor carries a reduced voltage from the 12 VDC output to the pulse return line. The
size of the pull-up resistor will vary depending on the amount of power needed to generate a
pulse. Figure 4-24 is an example of a connection to an open collector pulse transmitter using a
pull-up resistor. The Dispenser Compatibility List in Appendix B identifies the correct
applications for pullup resistors.
Do not connect more than 12 VDC to J4, J5, J6, or J7. Voltages greater than 12 VDC will damage the
Pedestal I/O Board.
Ne connectez pas plus de 12 volts courant continu à J4, J5, J6, ou J7. Plus de 12 volts courant continu
endommageront le tableau Dedans/Déhors du piédestal.
1) Determine the pulser wiring requirements by comparing the selected pulser with Figures 4-
18 through 4-24.
2) Pull a cable with enough conductors to make the necessary pulser connections.
3) Connect the 12 VDC pulser power feed to the +12V pin closest to the applicable P_ (P1 for
hose A, P2 for hose B, etc.) pin. If a pullup resistor is required, install the pullup resistor
between +12V and P_.
4) Connect the 12 VDC pulse return to P1 for hose A, P2 for hose B, etc.
5) Where required, connect the pulser common to 0V.
The maximum number of pulses that may be counted by the FMU when a PULSE FILTERING dipswitch
is turned on is 9000 per minute. Determine the number of pulses by multiplying the flow rate (i.e., 10
gallons/minute) times the divide rate (i.e., 100:1). If PULSE FILTERING is not turned on, the maximum
number of pulses increases to 120,000+ per minute.
6) If the pulser wires are pulled in the same conduit with AC control wires, and the pulser wires
are not shielded, turn on the applicable PULSE FILTERING dipswitch on the Satellite I/O
Control Board to prevent AC bleedover into the pulser wires.
7) Repeat steps a through f for each additional pulser to be installed.
FuelMaster
®
Installation Manual
CAUTION
ATTENTION
CAUTION
ATTENTION
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