3.7 Auto function, pressure sensor PCB (position 014D)
Auto function is a function for automatically regulate the motor power depending on the air pressure.
To the control PCB a pressure switch/sensor PCB is connected. The control PCB senses that the auto board
is connected and activates the software for automatic power regulation.
The Auto PCB is connected to the Control unit PCB like below sketch:
If pressure PCB is not connected, this will be indicated on the display by flashing the AUTO LED:s
with 1 Hz.
3.7.1 Functional description
When the pressure is too high the pressure switch is activated, and the controller starts to decrease
the power. When the switch is inactivated, depending on to low pressure, the controller starts to increase the
motor power until the switch activates.
In normal auto mode this means that the motor power will oscillate around the pressure setting of the
pressure switch.
EN Publication
number
599 71 19-22
Rev. 01
02/2009
PR - 34/42
