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EN-3P LIQUID LEVEL CONTROL RELAY
Features
ŸControls Level of Conductive Liquids in
Pump Up (Fill) or Pump Down (Drain)
Applications.
ŸAdjustable Sensitivity from 5K to 100K
ohms.
ŸDual Voltage 120 or 220 VAC Supply.
ŸLED Status Indication.
ŸProtects Pumps from Dry Running.
The EN-3P is a dual-probe conductive liquid level
control designed to monitor the levels of conductive
liquid and control the actuation of pumps or valves to
regulate levels. It is also suitable for protecting
submersible pumps against dry running or protecting
tanks from an"overflow". This device can also be used
to control dosing of liquids in mixing processes and to
protect heating elements in the event of non
immersion.
The sensitivity can be adjusted within the range of
5KΩ to 100KΩ by rotating the knob on the unit. This
sets the level at which the relay determines whether
liquid is present at the probe or not.
The EN-3P is dual voltage, it can be used with either
120 or 220 VAC.
Description
Voltage supply
To use a 220 VAC voltage supply use the terminals T1
and T3. To use a 120 VAC voltage connect the supply to
terminals T1 and T2. After the supply voltage is
connected the green LINE LED will turn ON.
Operation
220 VAC 120 VAC
T1 T1T3 T3T2 T2
PUMP DOWN (DRAIN) APPLICATION
The relay energizes when the liquid level comes in
contact with the high probe (PH) and remains
energized until the liquid level falls below the lower
probe (PL). To use this application place a wire
between terminals F/D and PC.
F/D PC
PUMP UP (FILL) APPLICATION
The relay energizes when the liquid level falls below
the low probe (PL) and remains energized until the
liquid level comes in contact with the high probe (PH).
To use this application leave terminals F/D and PC
disconnected.
PUMP DRY RUNNING PROTECTION
To protect the pump from dry running use the same
connections as the Pump Down (Drain) application
and connect the contact between NO and C in series
with the pump starter control.
F/D PC
F/D PC
SENSITIVITY ADJUSTMENT
To adjust the sensitivity within the range of 5KΩ to
100KΩ rotate the knob on the unit. This sets the level
at which the relay determines whether liquid is
present at the probe or not. For water it’s
recommended to set the sensitivity adjustment at 50K
Ω . To set the sensitivity follow the next procedure:
SENSITIVITY
75K
100K
5K
50K
25K
DANGER!
Potentially hazardous voltages are present. Electrical
shock can cause death or serious injury.
Installation should be done by qualified personnel
following all National, State & Local Codes.
BE SURE TO REMOVE ALL POWER SUPPLYING THIS
EQUIPMENT BEFORE CONNECTING OR
DISCONNECTING THE WIRING.
READ THE INSTRUCTIONS BEFORE INSTALLING OR
OPERATING THIS DEVICE.
KEEP THIS MANUAL FOR FUTURE REFERENCE.
