Pulsafeeder PULSAmatic 7120, Installation, Operation, & Maintenance Instruction

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replacement of the rear gearbox cover assembly. Refer to the pump operations manual
for the description of these operations.
Detailed circuit board schematics, containing component identifications, are available
from the factory to facilitate electronic circuit troubleshooting and repair at the board level.
The following conventions and procedures apply throughout this bulletin.
1. “Zero Stroke” refers to a zero, or (000) setting on the mechanical stroke counter.
“Full Stroke” refers to a full or (100) setting on the mechanical stroke counter.
2. A “low end” input control signal is one that commands the pump to zero stroke
A “high end” input control signal is one that commands the pump to full stroke.
Note that the signal values are inverted in the reverse acting option so that, for
example, a 4-20 mA signal commands full to zero stroke. In this case, 4 mA is the
high end signal. See “Options” under “principals of Operation” above for signal
definitions.
3. Pump stroke can be manually or automatically set as required for calibrations and
adjustments. References to the disable switch (“out” for manual, “in” for automatic)
may be omitted. Manual, or hand wheel adjustments made while the pump is not
operating, require that pressures be relieved from both the suction and discharge
lines.
4. Wiring terminals are indentified on the circuit board and referred to directly. For
example TB2-3 refers to terminal No. 3 on Terminal Board No. 2, (reference Figure
4).
CAUTION: When troubleshooting, always remove signal potential prior to
disconnecting AC power. This will help protect integrated circuits on the circuit
board.
4. INSTALLATION
4.1 Wiring Up
(Refer to any special wiring diagrams and installation drawings supplied by Pulsafeeder).
AC power lines should be routed to the actuator via a separate conduit from the control
signal and any optional accessory wiring. A separate switched and protected circuit is
recommended for the actuator power supply.
Remove the PULSAmatic actuator cover, which is secured by two screws, or screwed on,
in the case of an explosion proof enclosure. The two power transformers should be wired
as described by wiring diagrams. Power and ground wire should be No. 18 AWG wire
size or larger. A power ground screw is provided on the backing plate near the conduit
openings. Terminal TB1-4 is also provided as an optional circuit board ground. This
terminal is connected to the circuit board ground through a 4700 ohm resistor.
Run the signal and accessory wiring using the alternative conduit opening. No. 22 AWG
wire size or larger is recommended. Make all connections per the diagram that apply to
the combination of signal and accessories provided.
Explosion proof actuators are Underwriters Laboratories (UL) listed and are labeled with
the hazardous environments for which they are rated, along with any special installation