Liberty Pumps AE-Series - Manual (Page 10)

Operations
Three phase duplex panels are designed to operate
with three or four fl oats for pump sequencing. The
standard fl oat functions are common pump stop,
lead pump start, lag pump start/alarm (three fl oats),
or separate lag and alarm fl oats (four fl oats). Other
fl oat options, such as redundant off, are available.
Three Float Operation: As the liquid level passes
the stop fl oat and tips it to the ON (closed) position,
the panel will remain inactive. As the liquid level
tips the lead fl oat, the lead pump will start. If the
liquid level tips the lag/alarm fl oat, the lag pump
will start and the audio/visual alarm will activate.
Both pumps and the alarm will remain active until
the liquid level drops and the lag fl oat is in the
OFF (open) position. At this time the alarm will
silence. Both pumps will remain on until the liquid
level drops to normal and all three fl oats are in
the OFF (open) position. When both pumps have
stopped running, the alternator will switch the lead
pump and lag pump operating functions in the next
sequence.
Four Float Operation: The alarm will activate and
remain on only if the alarm fl oat is tipped to the ON
(closed) position.
Alarm System (Horn and Indicator)
When an alarm condition occurs, a red light and
a horn will be activated. If the test/normal/silence
switch is moved to the silence position, the horn will
be silenced. When the alarm condition is cleared,
the alarm system is reset. The alarm system can
be tested by moving the test/normal/silence switch
to the test position.
Control/Alarm Switch
Allows the control/alarm power to be turned on
or off.
HOA Switch
A hand-off-automatic switch is provided for each
pump. In the hand mode, the pump will turn on
unless other safety features are employed. In
the automatic mode, the pump will turn on from
commands by the fl oat switches.
Motor Protective Switch
A motor protective switch is supplied for each
pump to provide an adjustable overload, branch
circuit protection and disconnect. The overload
must be set in the fi eld. To set the overload, dial
the amp scale to the pump’s full load amp rating
(FLA). If the FLA’s are unknown, use a calibrated
amp meter to measure the pump amperage draw
under loaded conditions. An auxiliary contact is
wired in series with the magnetic contactor coil so
that on an overload trip, the magnetic contactor
will be disabled. In the event of an overload trip,
the motor protective switch must be reset by fi rst
turning the selector handle counterclockwise to
the OFF position and then turning the handle 90
o
clockwise to the ON position.
Control/Alarm Light
The light will illuminate when the control ON/OFF
switch is in the ON position.
Pump Run Lights
Each pump has a run light. The run light will be ON
in either the hand or the automatic mode when the
pump is called to run.
Float Status Lights
Lights will illuminate when the respective fl oat is in
the closed position.
Dry Auxiliary Contacts (optional)
Normally open - Contacts are open under normal
conditions and closed when alarm condition is
present.
Normally closed - Contacts are closed under
normal conditions and open when alarm condition
is present.
Both types automatically reset once alarm condition
is cleared.
Seal Failure Circuit and Indicator Light
(optional)
The seal fail circuit has resistance sensitivity and
will sense the presence of water in the pump seal
chamber. Upon installation, turn the sensitivity
dial on the seal fail module to the point where the
light turns on, then dial back slowly until the light
turns off. If water enters the seal chamber at this
point, the seal fail circuit will sense the change in
resistance. After a short time delay, the indicator
light will turn on. When the condition is cleared, the
relay will de-energize and the indicator light will turn
off. The seal fail relay has a sensitivity adjustment
so that false readings may be tuned out.
Thermal Cutout (optional)
The thermal cutout is wired in series with the
magnetic contactor coil. If the pump’s thermal
switch opens on high temperature, the contactor
will turn off and stop the pump. When the thermal
switch cools and closes, the magnetic contactor
will turn on if the pump is called to run.
NOTE: Some options ordered may not be included
in this manual.
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7228000B