EU declaration conformity
Fan speed controller | TK monitoring | remote start-stop | 1,5 A
Product description
Transformer fan speed controller with 5 speeds for single-phase motors with thermal contacts. The motor's maximum current is 1.5 A.
The fan speed may be adjusted using the rotary switch with the ON position. The digital inputs can be used to remotely enable or disable the motor.
In the event of overheating, the TK monitoring feature deactivates the motor. The motor will automatically resume after a power outage. The alarm and unregulated outputs can be used to operate external devices in order to produce alerts or validate normal operation.
The fan speed is controlled by lowering the motor voltage in 5 stages using autotransformers. This method produces an output voltage with a perfect sinusoidal form, ensuring silent motor running.
The enclosure is surface mountable and provides IP54 protection against dirt, dust, and moisture entry.
Documents
Additional specifications and description
5-step fan speed controller with extra features
Via the rotary switch with 5 positions, fan speed can be set. There is also an OFF position to switch off the motor. Autotransformer technology is used to reduce the motor voltage and the fan speed in 5 steps. This speed controller is therefore only suitable for voltage controllable motors. If you are not sure whether your motor is voltage controllable, it is best to contact the motor manufacturer. Autotransformer technology is very reliable and robust. It generates a motor voltage with perfect sinusoidal shape. This results in exceptionally quiet motor operation and extended service life. A special impregnated coating reduces the electrical noise from the autotransformers.
Fans with TK contact can be thermally monitored
This fan speed regulator offers the same speed control as the standard STR-1 series with some extra options. One of these is the possibility to monitor thermal motor contacts. TK or thermal contacts monitor the temperature inside the motor windings. In case of motor overheating, the TK monitoring function will disable the motor to prevent motor damage and activate the alarm output. If the motor is not equipped with TK contacts, both TK terminals of the controller must be bridged to simulate normal motor temperature.
Inputs offer remote control possibilities
Furthermore, the STRA1 series offers more control options thanks to the extra inputs. Via these inputs, the motor can be remotely enabled or disabled. This can be used, for example, to connect a door contact to control an air curtain. When the door is opened, the door contact activates the air curtain via the input of the STRA1 controller. The air curtain will run at a fixed speed, set via the rotary switch. Another example is to connect a smoke alarm to the input. If a smoke alarm occurs, the motor will be disabled - regardless the status of the other input. In this way, the spread of the toxic smoke gases through the ventilation system can be slowed down.
Outputs to control external devices
The extra, unregulated output (230 VAC) is active when the motor is enabled. Because this output is either ON (230 Volt) or OFF (0 Volt), it is called ‘unregulated output'. The maximum current of this output is 2 A. This output can be used to control an indicator lamp, to open the closing grids of the air ducts, to activate lighting, etc. The device connected to this output will operate simultaneously with the fan.
Auto reset after power failure
In case of a power failure, this controller will automatically reset itself. When the power is restored, the motor will restart automatically. With standard fan speed controllers, after a power failure, the rotary switch must be turned manually to the OFF position and then back to the desired speed position. This is not necessary with the STRA1 series.
Enclosure for indoor wall mounting
Make sure that the fan speed controller can cool sufficiently. Preferably install it in a cool place, best not in direct sunlight. The enclosure is designed and manufactured in-house. We use high-quality r-ABS VO (UL94) plastic. This material is flame extinguishing, very tough and offers good protection against impacts. It offers an IP54 protection against ingress dust and water. This fan speed controller can be installed on a wall or panel indoors.
Remarks, reviews & ratings