Dover PSG Neptune, Installation Operation & Maintenance

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DILUTION WATER FLOW CONTROL
1. The flowmeter indicates the dilution water flow rate. The water flowing through the flowmeter does not
contain any polymer.
2. The flowmeter control knob is used for adjusting the dilution water flow rate.
POLYMER FLOW CONTROL
1. The feed pump controls the amount of polymer being metered into the system. Depending upon the
type of feed pump, there may be pump speed and/or stroke length control. These adjustments are both
on the pump for the electronic solenoid pumps. The speed control is on the face of the Polymaster for
remote, motor driven pump models. There may also be a stroke length adjustment on remote pump
models, depending on type of pump used.
2. For electronic metering pumps, and optional remote control mode may have been provided.
Please consult the system specific electrical drawings.
3. Two types of Polymaster are offered, manual or automatic.
Model numbers beginning with PMD are “MANUAL” units and allow only for manual adjustment of
the polymer flow. For electronic pumps, this may be by manual speed or manual stroke length
adjustment or both. For motor driven diaphragm metering pumps, this will be by manual stroke length
adjustment only. All other motor driven pumps including progressive cavity or rotary gear pumps are
provided with a variable drive for speed adjustment.
Model numbers beginning with PAD are “AUTOMATIC UNITS” control the polymer flow rate
automatically in response to a 4-20 mA signal. Electronic metering pumps use the 4-20 mA signal to
control stroking speed, while providing a separate stroke length control. Motor driven diaphragm
metering pumps also use the 4-20 mA signal to control pump speed while preserving a separate stroke
length control. All other motor driven pumps including progressive cavity or roto gear types, speed
adjustment will be proportionally to the 4-20mA input signal.
Electronic metering pumps will follow the 4-20 mA signal when the speed control mode is turned to the
”EXT” position.
Automatic units using motor driven pumps have a speed dial on the front panel of the Polymaster which
can be used to manually adjust the motor speed when the “MAN-AUTO” switch of the faceplate of the
SCR drive is in the “MAN” position. The 4-20 mA signal will drive the pump when SCR drive toggle
is in the “AUTO” position.
Please refer to the pump instruction manuals furnished for the particular unit.