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.webp "Day-night fan speed controller")
EU declaration conformity
Fan speed controller 400 V | day-night function | 2,5 A
Product description
This is a two-speed controller for 400 V motors with thermal contacts (TK). The (combined) maximum motor current is 2,5 A.
The controller has two independent 5-speed switches to select two optimum fan speeds. When the motor is active, both speeds can be switched via a dry contact input.
The TK monitoring function stops the motor in case of overheating. The motor restarts automatically after a power failure.
Alarm and unregulated outputs can be used to control external devices to generate alerts or control normal operation.
The fan speed is regulated by lowering the motor voltage through an autotransformer. This technology produces an excellent sinusoidal output voltage and guarantees quiet operation of the motor.
The enclosure can be surface mounted and has IP54 protection class against ingress of dirt, dust and moisture.
The supply voltage is 400 VAC.
Additional specifications and description
Operation
The SC2A4 series designed to control 400 VAC, 3-phase fans using autotransformer technology. The series use two 5-step rotary switches to select two optimal fan speeds. These speeds can be selected for different application, such as high speed during the day and low speed during the night. The output voltages are preset. The high speeds are 210, 250, 290, 330 and 400 VAC and the low speeds are 130, 170, 210, 250 and 290 VAC. These are switched via a dry contact input when the motor is active. For example, an external clock/timer can trigger the switches to high speed during the day and low speed during the night.
Wiring
When connecting a three-phase fan motor, following the specific instructions to ensure proper connections and safe operation is of crucial importance.
First, you should identify the motor leads. Three-phase motors have six leads that are labeled as U, V, and W, denoting the three phases. These leads serve as the outputs to the motor, while the controller is powered using the R, S, and T terminals.
To determine the appropriate wiring configuration, you should refer to the motor nameplate or specifications. Specifically, check the voltage rating of the motor and ensure that it matches the available power supply voltage.
Depending on the motor voltage and the available power supply, it may be necessary to wire the motor in either a delta (Δ) or a star (Y) configuration. The motor nameplate or the manufacturer's documentation should provide instructions on the suitable wiring configuration for your specific motor model.
Also, three-phase motors require proper grounding for safety purposes.
By following these rules, you can ensure the wiring for your three-phase fan motor is correctly executed and that safe operation is achieved.
Extra features
The SC2A4 series of transformer-based fan speed controllers by Sentera offers specific features that set it apart from other series. The key distinguishing feature is the inclusion of two optimal fan speeds that can be selected via knobs (switches) on the enclosure.
The series also features:
Remote start-stop: The fan motor can be enabled or disabled using two inputs: normally open and normally closed. By connecting a remote switch to the normally open input, the motor can be turned on or off from a distance. Similarly, a smoke alarm connected to the normally closed input will deactivate the motor in the event of a smoke alarm event. This feature offers convenient control of the fan motor remotely.
Unregulated output: The controller includes an additional unregulated output (single phase, 230 VAC) that becomes active when the motor is enabled. This output can be utilized to control external devices, such as operation indicators or dampers. For example, when the fan motor is deactivated, the damper can be closed, and when the fan motor is active, the damper can be opened.
Thermal motor protection monitoring: The controller can monitor thermal motor contacts (TK) that measure the temperature in the motor windings. If the motor exceeds safe temperature limits, the TK monitoring function will disable the motor to prevent damage. In cases where the motor does not have TK contacts, the TK terminals of the controller must be bridged to simulate normal motor temperature.
Alarm output: In the event of motor problems, such as overheating, an alarm output (230 VAC) is activated. This output can be used to generate alerts or control warning indications. If the motor exceeds safe temperature limits, the TK monitoring function will disable the motor to prevent further damage.
Auto reset after power failure: If a power failure occurs, the controller has an automatic reset feature. Once the power is restored, the controller will reset itself, and the fan motor will restart automatically. This ensures a seamless operation of the system without the need for manual intervention after power disruptions.
Steel enclosure
The metal enclosure is coated with paint that provides resistance against external mechanical impacts. With an IP54 ingress protection rating, these enclosures are designed to offer a high level of protection against dust and water ingress. They are effectively sealed to prevent the entry of dust particles and can withstand water splashes from all directions, making them suitable for moderately harsh environments.
The SC2A4 series designed to control 400 VAC, 3-phase fans using autotransformer technology. The series use two 5-step rotary switches to select two optimal fan speeds. These speeds can be selected for different application, such as high speed during the day and low speed during the night. The output voltages are preset. The high speeds are 210, 250, 290, 330 and 400 VAC and the low speeds are 130, 170, 210, 250 and 290 VAC. These are switched via a dry contact input when the motor is active. For example, an external clock/timer can trigger the switches to high speed during the day and low speed during the night.
Wiring
When connecting a three-phase fan motor, following the specific instructions to ensure proper connections and safe operation is of crucial importance.
First, you should identify the motor leads. Three-phase motors have six leads that are labeled as U, V, and W, denoting the three phases. These leads serve as the outputs to the motor, while the controller is powered using the R, S, and T terminals.
To determine the appropriate wiring configuration, you should refer to the motor nameplate or specifications. Specifically, check the voltage rating of the motor and ensure that it matches the available power supply voltage.
Depending on the motor voltage and the available power supply, it may be necessary to wire the motor in either a delta (Δ) or a star (Y) configuration. The motor nameplate or the manufacturer's documentation should provide instructions on the suitable wiring configuration for your specific motor model.
Also, three-phase motors require proper grounding for safety purposes.
By following these rules, you can ensure the wiring for your three-phase fan motor is correctly executed and that safe operation is achieved.
Extra features
The SC2A4 series of transformer-based fan speed controllers by Sentera offers specific features that set it apart from other series. The key distinguishing feature is the inclusion of two optimal fan speeds that can be selected via knobs (switches) on the enclosure.
The series also features:
Remote start-stop: The fan motor can be enabled or disabled using two inputs: normally open and normally closed. By connecting a remote switch to the normally open input, the motor can be turned on or off from a distance. Similarly, a smoke alarm connected to the normally closed input will deactivate the motor in the event of a smoke alarm event. This feature offers convenient control of the fan motor remotely.
Unregulated output: The controller includes an additional unregulated output (single phase, 230 VAC) that becomes active when the motor is enabled. This output can be utilized to control external devices, such as operation indicators or dampers. For example, when the fan motor is deactivated, the damper can be closed, and when the fan motor is active, the damper can be opened.
Thermal motor protection monitoring: The controller can monitor thermal motor contacts (TK) that measure the temperature in the motor windings. If the motor exceeds safe temperature limits, the TK monitoring function will disable the motor to prevent damage. In cases where the motor does not have TK contacts, the TK terminals of the controller must be bridged to simulate normal motor temperature.
Alarm output: In the event of motor problems, such as overheating, an alarm output (230 VAC) is activated. This output can be used to generate alerts or control warning indications. If the motor exceeds safe temperature limits, the TK monitoring function will disable the motor to prevent further damage.
Auto reset after power failure: If a power failure occurs, the controller has an automatic reset feature. Once the power is restored, the controller will reset itself, and the fan motor will restart automatically. This ensures a seamless operation of the system without the need for manual intervention after power disruptions.
Steel enclosure
The metal enclosure is coated with paint that provides resistance against external mechanical impacts. With an IP54 ingress protection rating, these enclosures are designed to offer a high level of protection against dust and water ingress. They are effectively sealed to prevent the entry of dust particles and can withstand water splashes from all directions, making them suitable for moderately harsh environments.
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