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EU declaration conformity
Fan speed controller 400 V | TK monitoring | remote run-stop | 14 A
Product description
This 5-step fan speed controller for 3-phase 400 VAC motors features thermocontacts or TK. The maximum motor current of 14 A. The speed is adjusted via the manual switch on the door of the enclosure. The motor can be enabled and disabled remotely via the additional inputs.
For motor protection, STRA4 has a thermal monitoring function. In case of motor overheating, the TK monitoring functionality deactovates the motor to prevent damage. The motor restarts automatically without the need of manual intervention.
STRA4 also has an alarm output and an unregulated output. The alarm output triggers external alert modules. The unregulated output can control external devices to confirm normal operation or enable connected equipment.
Fan speed is regulated by reducing the motor voltage using transformer technology. This ensures that the output voltage has a perfect sinusoidal shape, guaranteeing smooth motor operation.
The controller is designed for surface mounting. Its enclosure has IP54 ingress protection rating against particles and moisture.
Additional specifications and description
Silent motor operation and long service life
The STRA4 is a speed controller for 400 VAC three-phase alternating current motors (AC fans). It is equipped with autotransformers that reduce the motor voltage in 5 steps. This technique ensures a perfect sinusoidal shape and guarantees very quiet operation and a long motor life. A special coating on the autotransformers also ensures quiet operation of the speed controller itself. Autotransformer-based variable speed drives provide the most robust and simple solution for voltage-controllable AC motors. Since the motor regulated using this controller operates noiselessly, it is appropriate for noise-sensitive settings.
Easy to connect
The STRA4 speed controller can be connected quickly and easily. No specific settings or adjustments are necessary to make the device operational. Simply connect the regulated output to the motor then connect the drive to the mains.
When wiring a three-phase fan motor, specific guidelines need to be followed to ensure correct connections and safe operation. The motor leads are typically labeled U, V, and W for the three phases, while the controller is supplied using the R, S, and T terminals. The motor voltage should match the available power supply voltage. Depending on the motor voltage and power supply, the motor may need to be wired in either a delta (Δ) or star (Y) configuration, as indicated by the motor nameplate or manufacturer's documentation. Grounding guidelines specified by local electrical codes should also be followed.
Optional connections
Remote ON and OFF: The STRA4 is equipped with 2 dry contacts which can be used to turn the drive on and off remotely using a switch or thermostat.
Motor thermal protection: This speed controller can monitor the motor thermal contacts (TK or thermal contacts measure the temperature in the motor windings). If the motor overheats, the TK monitoring function will disable the motor to prevent damage to the motor. If your motor is not equipped with TK contacts, bridge the two TK terminals to simulate normal motor temperature.
Alarm output: The STRA4 speed controller also has an alarm output which is activated as soon as the thermal protection has turned off the device. This alarm output can be linked to an audible or visual alarm.
Automatic restart after power outage: The STRA4 automatically restarts after a power outage. No manipulation or intervention is therefore necessary to make the drive operational after a power outage.
Unregulated output: The STRA4 has an unregulated 230 VAC output. This output becomes active whenever the regulated output to the motor is activated and can be used to open a gas valve, air damper actuator or supplemental lighting.
Solid and robust housing
The STRA4 housing is made of steel and is designed for wall mounting. It offers protection against dust and humidity according to the IP54 classification. It provides protection against dust and humidity.
This fan speed controller is designed for indoor installation on walls or panels. To ensure optimal cooling and performance:
• Select a cool installation location.
• Avoid direct sunlight and high-temperature areas.
• Use the controller exclusively for indoor applications.
The STRA4 is a speed controller for 400 VAC three-phase alternating current motors (AC fans). It is equipped with autotransformers that reduce the motor voltage in 5 steps. This technique ensures a perfect sinusoidal shape and guarantees very quiet operation and a long motor life. A special coating on the autotransformers also ensures quiet operation of the speed controller itself. Autotransformer-based variable speed drives provide the most robust and simple solution for voltage-controllable AC motors. Since the motor regulated using this controller operates noiselessly, it is appropriate for noise-sensitive settings.
Easy to connect
The STRA4 speed controller can be connected quickly and easily. No specific settings or adjustments are necessary to make the device operational. Simply connect the regulated output to the motor then connect the drive to the mains.
When wiring a three-phase fan motor, specific guidelines need to be followed to ensure correct connections and safe operation. The motor leads are typically labeled U, V, and W for the three phases, while the controller is supplied using the R, S, and T terminals. The motor voltage should match the available power supply voltage. Depending on the motor voltage and power supply, the motor may need to be wired in either a delta (Δ) or star (Y) configuration, as indicated by the motor nameplate or manufacturer's documentation. Grounding guidelines specified by local electrical codes should also be followed.
Optional connections
Remote ON and OFF: The STRA4 is equipped with 2 dry contacts which can be used to turn the drive on and off remotely using a switch or thermostat.
Motor thermal protection: This speed controller can monitor the motor thermal contacts (TK or thermal contacts measure the temperature in the motor windings). If the motor overheats, the TK monitoring function will disable the motor to prevent damage to the motor. If your motor is not equipped with TK contacts, bridge the two TK terminals to simulate normal motor temperature.
Alarm output: The STRA4 speed controller also has an alarm output which is activated as soon as the thermal protection has turned off the device. This alarm output can be linked to an audible or visual alarm.
Automatic restart after power outage: The STRA4 automatically restarts after a power outage. No manipulation or intervention is therefore necessary to make the drive operational after a power outage.
Unregulated output: The STRA4 has an unregulated 230 VAC output. This output becomes active whenever the regulated output to the motor is activated and can be used to open a gas valve, air damper actuator or supplemental lighting.
Solid and robust housing
The STRA4 housing is made of steel and is designed for wall mounting. It offers protection against dust and humidity according to the IP54 classification. It provides protection against dust and humidity.
This fan speed controller is designed for indoor installation on walls or panels. To ensure optimal cooling and performance:
• Select a cool installation location.
• Avoid direct sunlight and high-temperature areas.
• Use the controller exclusively for indoor applications.
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