TrolMaster BETA-2 Day and Night Fan Speed Controller | 25 to 100%

What the TrolMaster Beta-2 Does Between On and Off

A thermostat gives a fan two states. This gives it a hundred. As room temperature climbs the controller raises fan speed, and as it falls the speed comes back down. Extraction then tracks the heat load instead of cycling around it. Speed range runs from twenty-five percent up to full. That floor matters, because a fan held below its minimum stalls rather than turning slowly. Temperature accuracy is one degree Fahrenheit. A photocell inside the unit reads room light and switches between the day and the night set points. No timer is needed and nothing is wired to the lighting circuit. Most rooms want a different target once the lamps are off, and this is how that gets handled. The digital display shows the current reading and the settings together. A temperature sensor comes in the box with the controller. Input is a hundred and twenty volts AC on a cord of 1.8 m, protected by a six amp fuse.

Why the Triac Output Decides Which Fans This Suits

Check the fan before this arrives, because the output type rules out a whole category of them. The switching element is a triac, which varies speed by chopping the AC waveform. That works on a shaded pole or an AC induction fan, which is what most inline extraction fans used before the last few years. It does not work on an EC fan or on anything expecting a nought to ten volt or PWM control signal. An EC motor has its own drive electronics inside it and feeding those a chopped waveform can damage them. TrolMaster sell a separate adaptor for EC fans, so the answer for that case is a different part rather than this one. Look at the fan label or its manual before deciding. The fuse behind the output is rated at six amps, which is the real ceiling on what can be attached. The packed unit measures 275 by 87 by 94 mm and weighs 0.56 kg.

Key Features

• Control: Varies fan speed against temperature rather than switching on and off
• Speed range: Twenty-five to a hundred percent of full output
• Photocell: Built in, switching between day and night set points automatically
• Accuracy: One degree Fahrenheit
• Display: Digital, showing the reading and the settings together
• Output type: A triac, which suits shaded pole and AC induction fans
• Not for: EC fans, or anything needing a nought to ten volt or PWM signal
• Fuse: Six amps, which is the working ceiling on the attached load
• Input: A hundred and twenty volts AC, on a 1.8 m cord
• In the box: The controller and a temperature sensor

Technical Specifications