Pressure
Sensor
Boot
Remove Rubber End Cap To Adjust Pressure
With 7/32" Allen Wrench (provided)
Figure 5A: Pressure Sensor
12. The pressure sensor communicates the system pressure to the SubDrive controller. The sensor is preset at
the factory to 3.4 bar, but can be adjusted by the installer using the following procedure:
a. Remove the rubber end-cap (Figure 5A).
b. Using a 7/32" Allen-wrench (provided), turn the adjusting screw clockwise to increase pressure and
counter-clockwise to decrease pressure. The adjustment range is between 1.7 and 5.5 bar (1/4 turn =
approximately 0.2 bar)).
c. Replace the rubber end cap.
d. Cover the pressure sensor terminals with the rubber boot provided (Figure 5A).
10. Connect the other end of the pressure sensor cable with the
two spade terminals to the pressure sensor. The connections
are interchangeable (Figure 5A).
11. Set the pressure tank pre-charge at 70% of the desired water
pressure setting. To check the tank’s pre-charge, de-pressurize
the water system by opening a tap. Measure the tank pre-
charge with a pressure gauge at its inflation valve and make
the necessary adjustments.
NOTE:
Ensure that the system is properly grounded all the way to the service entrance panel. Improper grounding
may result in the loss of voltage surge protection and interference filtering.
When increasing the pressure, do not exceed the mechanical stop on the pressure sensor or 5.5 bar. The
pressure sensor may be damaged.
INFO
Start-Up and Operation
Apply power to the controller. A steady green light indicates that the SubDrive has power but the pump is not running.
The green light will flash continuously when the pump is running.
Leaky Systems
Leaky water systems might keep the controller running due to the accurate pressure sensing capability of the pressure
sensor. Continuous running or starts and stops do not hurt the controller, pump or motor. However, to reduce the on-
time of the controller/pump/motor, a “Bump-Mode” procedure is installed. During low flow (or leaky) conditions, this
feature periodically increases the system pressure slightly above the set point and shuts off the pump. This adds some
time to bleed off before the system starts up again.
NOTE:
Conventional private water systems intermittently fill a pressure tank as commanded by a standard pressure switch
2 - 3.4 bar. The SubDrive maintains a constant pressure at the pressure sensor up to the maximum capability of the
motor and pump.
Although the pressure is constant at the pressure sensor, pressure drops may be noticeable in other areas of the
home when additional taps are opened. This is due to restrictions in the plumbing and will be more pronounced
the farther the taps are from the pressure sensor. This would be true of any system, and if observed, should not be
interpreted as a failure in the performance of the SubDrive.
16
Technical changes without notice / Techn. Änderungen vorbehalten / Modifications techniques réservées sans préavis / 5930
