Additional specifications and description
What is a 3-step control switch?
The output voltage of this control switch varies according to the position of the rotary switch. The output voltage is divided in three steps. This control switch controls EC fans or damper actuators in three steps. It can also remotely control AC fan speed controllers (EVS or MVS series) or frequency inverters (FI-E series) in three steps. E.g. the control switch can be installed in the living room while the fan speed controller is located in a technical room or electrical cabinet.
Adjustable output levels
For some applications, it is desirable to adjust the control signal in order to obtain the optimal fan speed. The control signal of position 1 and position 2 can be adjusted. Via internal trimmers the output voltages of these positions can be set in the range of 1 – 10 VDC. Position 3 always equals the supplied voltage: 10 VDC.
In some occasions, it is technically or legally required to ensure a minimum air supply in all circumstances. The fan speed must never drop below a minimum level. Since this control switch does not have an OFF-position, the control signal will never reach 0 V. Even in position 1, the control signal will be minimum 1 VDC (this minimum output voltage can be adjusted via the built-in trimmer.)