Most ZIEHL-ABEGG external rotor motors are voltage controllable. For simple and cost-effective speed control of these motors and fans, transformer-based controllers are available. These can be supplied in various versions. In addition to versions that only generate the corresponding voltage by setting the 5-stage switch, there are also devices that can control dampers or valves.

Versions, that switch between two adjustable stages via an external contact, are also available. Versions, that are controlled via a 5-step thermostat, are also available. Another, great advantage of transformer-based control devices is speed control without electromagnetic excitation in the motors. The products are therefore also recommended for areas that are sensitive of noise.

Correspondingly, we supply thermostats which can be combined without the need of transformer-based controllers.