Transformer fan speed controllers
Transformer fan speed controllers are intended for stepped speed control of the electric motors. They use autotransformer technology to reduce the motor voltage – and fan speed - in steps. Thanks to this technology, they generate a motor voltage with a perfect sinusoidal shape. This results in exceptionally quiet motor operation and extended service life.
Autotransformers are electrical transformers with a single coil. Via their different voltage taps, reduced voltages are available. A special impregnated coating reduces the electrical noise from the autotransformers. However, in quiet environments the typical humming noise caused by the transformer technology might be noticeable.
Transformer fan speed controllers are cost efficient and have proven to be very reliable and robust. They can also be used in circumstances with unstable power supply.
These type of fan speed controllers are easy to install. They don’t require any configuration. Some transformer fan speed controllers have an integrated rotary switch to manually adjust the fan speed. Other variants can be controlled remotely via Modbus RTU or via an analogue control signal.