.webp "3 ph controller AC fan")
.webp "3 ph controller extraction fan")
.webp "3 ph controller HVAC fan")
.webp "3 ph controller exhaust fan")
.webp "3 ph controller axial fan")
EU declaration conformity
Fan speed controller 400 V | TK monitoring | remote run-stop | 8 A
Product description
This is a 5-step fan speed controller for 3-phase 400 VAC motors, which features thermal contacts. The motor current of 8 A. The speed is adjusted manually via the switch. The motor can be turned on or off remotely using the extra inputs.
For motor safety, STRA4 has a thermal monitoring function. In the event of motor overheating, the TK monitoring function disables the motor to prevent possible failure.
The motor restarts automatically without the need for manual intervention in case of power failure.
STRA4 includes an alarm output and an unregulated output. The alarm output triggers external alert modules. The unregulated output can control external equipment to confirm normal operation or enable connected devices.
Fan speed is controlled by reducing the motor voltage using transformer technology. This ensures that the output voltage has a perfect sine shape, guaranteeing smooth motor operation.
The controller is surface mountable and its enclosure has IP54 ingress protection rating against particles and moisture.
Additional specifications and description
The technology
Autotransformer technology, utilized in the fan speed controller, is a method of controlling the speed of AC motors by adjusting the voltage supplied to the motor. It involves the use of a single winding with multiple taps along the winding, allowing for variable voltage output.
The benefits of using autotransformer technology in fan speed control include:
Energy efficiency: By reducing the motor voltage, the fan speed controller reduces power consumption, leading to energy savings.
Smooth operation: The sinusoidal voltage output of the autotransformer ensures quiet and vibration-free motor operation, enhancing user comfort.
Long service life: The autotransformer generates a voltage with sinusoidal waveform contributing to the longevity of the motor by reducing stress and wear on motor components.
Reliability: Autotransformers are known for their robustness and reliability, making them suitable for demanding applications.
Special features
The STRA4 series is similar to the basic STR-4 series of Sentera but has some extra features added, namely:
Remote start-stop: The controller provides inputs for remote control of the motor. There are two input options: a normally open (NO) input and a normally closed (NC) input. By connecting a remote switch to the NO input, the motor can be remotely enabled or disabled. Additionally, a smoke alarm can be connected to the NC input. If a smoke alarm is triggered, regardless of the state of the other input, the motor will be disabled.
Thermal motor protection: The fan speed controller has the capability to monitor thermal motor contacts, also known as TK contacts. These contacts measure the temperature in the motor windings. If the motor overheats, the TK monitoring function will disable the motor to prevent damage. If the motor is not equipped with TK contacts, the TK terminals of the controller must be bridged to simulate normal motor temperature.
Alarm output: The controller features an alarm output (230 VAC) that is activated when motor problems occur. This output can be used to generate alerts or activate warning lights. For instance, in the event of motor overheating, the alarm output is activated, and the motor is disabled by the TK monitoring function to prevent further damage.
Auto reset: In the event of a power failure, the controller automatically resets itself. When power is restored, the motor restarts automatically without the need for manual intervention.
Standard features
Unregulated output: As standard, an additional unregulated output (230 VAC, 2 A) is available on the controller. This output becomes active when the motor is enabled. It can be used to control external devices such as run indicators, dampers, or other equipment. For example, when the fan is deactivated, the damper can be closed, and when the fan is active, the damper can be opened using this output.
Solid enclosure made of sheet steel: Sentera’s 400 VAC controllers are housed in a high-quality steel enclosures. They are designed for surface mounting and provide an IP54 protection rating. This rating ensures protection against the ingress of dirt, dust, and moisture, making it suitable for indoor installations.
Can the fan speed be adjusted manually or only through the remote control?
The fan speed controller allows for manual adjustment of the fan speed through the rotary switch on its enclosure. The rotary switch is located on the controller itself and provides five different speed positions, ranging from low speed (position 1) to high speed (position 5). Users can manually select the desired speed by turning the switch to the corresponding position.
In addition to manual adjustment, the fan speed controller also offers the capability for remote control switching. It provides inputs for remote start-stop functionality, where a remote switch can be connected to enable or disable the motor remotely. However, the remote control feature is an additional option and does not replace setting the fan speed using the rotary switch on the controller itself.
Autotransformer technology, utilized in the fan speed controller, is a method of controlling the speed of AC motors by adjusting the voltage supplied to the motor. It involves the use of a single winding with multiple taps along the winding, allowing for variable voltage output.
The benefits of using autotransformer technology in fan speed control include:
Energy efficiency: By reducing the motor voltage, the fan speed controller reduces power consumption, leading to energy savings.
Smooth operation: The sinusoidal voltage output of the autotransformer ensures quiet and vibration-free motor operation, enhancing user comfort.
Long service life: The autotransformer generates a voltage with sinusoidal waveform contributing to the longevity of the motor by reducing stress and wear on motor components.
Reliability: Autotransformers are known for their robustness and reliability, making them suitable for demanding applications.
Special featuresThe STRA4 series is similar to the basic STR-4 series of Sentera but has some extra features added, namely:
Remote start-stop: The controller provides inputs for remote control of the motor. There are two input options: a normally open (NO) input and a normally closed (NC) input. By connecting a remote switch to the NO input, the motor can be remotely enabled or disabled. Additionally, a smoke alarm can be connected to the NC input. If a smoke alarm is triggered, regardless of the state of the other input, the motor will be disabled.
Thermal motor protection: The fan speed controller has the capability to monitor thermal motor contacts, also known as TK contacts. These contacts measure the temperature in the motor windings. If the motor overheats, the TK monitoring function will disable the motor to prevent damage. If the motor is not equipped with TK contacts, the TK terminals of the controller must be bridged to simulate normal motor temperature.
Alarm output: The controller features an alarm output (230 VAC) that is activated when motor problems occur. This output can be used to generate alerts or activate warning lights. For instance, in the event of motor overheating, the alarm output is activated, and the motor is disabled by the TK monitoring function to prevent further damage.
Auto reset: In the event of a power failure, the controller automatically resets itself. When power is restored, the motor restarts automatically without the need for manual intervention.
Standard features
Unregulated output: As standard, an additional unregulated output (230 VAC, 2 A) is available on the controller. This output becomes active when the motor is enabled. It can be used to control external devices such as run indicators, dampers, or other equipment. For example, when the fan is deactivated, the damper can be closed, and when the fan is active, the damper can be opened using this output.
Solid enclosure made of sheet steel: Sentera’s 400 VAC controllers are housed in a high-quality steel enclosures. They are designed for surface mounting and provide an IP54 protection rating. This rating ensures protection against the ingress of dirt, dust, and moisture, making it suitable for indoor installations.
Can the fan speed be adjusted manually or only through the remote control?
The fan speed controller allows for manual adjustment of the fan speed through the rotary switch on its enclosure. The rotary switch is located on the controller itself and provides five different speed positions, ranging from low speed (position 1) to high speed (position 5). Users can manually select the desired speed by turning the switch to the corresponding position.
In addition to manual adjustment, the fan speed controller also offers the capability for remote control switching. It provides inputs for remote start-stop functionality, where a remote switch can be connected to enable or disable the motor remotely. However, the remote control feature is an additional option and does not replace setting the fan speed using the rotary switch on the controller itself.
Remarks, reviews & ratings