Electrical
Pressure Switch Wiring
The pressure switch is pre-wired to the motor.
1. Unplug the pump to remove power.
2. Remove the pressure switch cover.
3. Attach a
volt cable to the pressure switch as
shown. Either wire can connect to either terminal.
4. Attach the pressure switch cover.
Checking Tank Pressure
The pressure tank is pre-charged with air pressure.
This must be adjusted when first installed, and re-
checked periodically.
The pressure switch is pre-set to 2 / 3.4 bar (30 / 50 PSI).
The tank pre-charge pressure should be set to 1.93 bar
(28 PSI).
If the system cut-in pressure is changed, then the tank
pre-charge pressure must be changed.
To change or check tank pre-charge pressure:
1. Turn off power to the pump.
2. Close the suction line valve from the storage tank.
3. Open a faucet to drain pressure from the tank.
Motor wires connect here.
Power supply wires connect here.
Volt: Connect one hot wire (black or
red) to one of these screws (it doesn't
matter which one). Connect the white
(neutral) wire to the other screw. Cap any
remaining black or red wires.
Clamp the power cable to prevent strain
on the terminal screws.
Connect the green (or bare copper) ground wire
to the either green ground screw.
Figure 4 – Pressure Switch Wiring.
4. Use an air pressure gauge (same as used on automo-
bile tires), and check the air pressure from the air fit-
ting on top of the tank.
System Cut-In
Pressure
1.38 Bar (20 PSI)
2.07 Bar (30 PSI)
2.76 Bar (40 PSI)
The tank pre-charge pressure should always be 0.138 Bar
(2 PSI) less than the cut-in (start) pressure (see chart
above).
5139 1005
Tank
Precharge
1.24 Bar (18 PSI)
1.93 Bar (28 PSI)
2.62 Bar (38 PSI)
Changing Pressure Switch Settings
The pressure switch is pre-set to 2 / 3.4 Bar (30 / 50 PSI).
The pressure cut-off (pump-stop pressure) can be
changed if required.
To change cut-off (pump stop) and cut-on (pump start)
pressure together:
1. Turn off power to the pump.
2. Remove the cover to the pressure switch.
Pressure
Adjustor #2
Figure 5 – Pressure Switch.
3. Turn pressure-adjustor #1 clockwise to increase both
cut-off and cut-in pressure. Each turn will change the
pressure setting 0.17 Bar (2.5 PSI). Turn the adjustor
counterclockwise to lower the pressure setting.
4. To raise only the cut-off pressure, turn pressure adjus-
tor #2 clockwise. Each turn will change the pressure
setting 0.17 Bar (2.5 PSI). Turn the adjustor counter-
clockwise to lower the pressure setting.
Checking Pressure Adjustment
1. After changing the pressure setting, put the cover on
the pressure switch.
2. Apply power.
3. If the pump does not start up, open a faucet to drain
water from the pressure tank.
4. Watch the pressure gauge and note at what pressure
the pump starts.
5. Close the faucet.
6. Watch the pressure gauge and note at what pressure
the pump stops.
7. If additional adjustments need to be made, refer to
the previous procedure.
Pressure
Adjustor #1
Attach Power
Wires Here
Attach Ground
Wire Here
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