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EU declaration conformity
Fan speed controller 400 V | day-night function | 6 A
Product description
Two-speed controller for 400 V motors with thermal contacts (TK). The maximum motor current is 6 A.
The controller has two independent 5-speed switches to select the 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 reducing 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.
Additional specifications and description
The SC2A4 series is specifically designed to control 400 VAC, 3-phase fans using autotransformer technology. It features two 5-step rotary switches that allow the selection of two optimal fan speeds. These speeds can be chosen based on specific applications, such as high speed during the day and low speed during the night. The output voltages for each speed setting are preconfigured.
For high speeds, the available voltages are 210, 250, 290, 330, and 400 VAC, whilst for low speeds, the options are 130, 170, 210, 250, and 290 VAC. These voltage settings can be switched using a dry contact input while the motor is active.
By utilizing the SC2A4 series, you can easily and flexibly control the fan speeds to meet specific requirements at different times of the day or for different applications.
Two-step fan speed selection
The controller includes two separate 5-step rotary switches that allow you to select two optimal fan speeds. These speeds can be customized for different scenarios, such as high speed during the day and low speed during the night. This enables energy efficiency and tailored fan performance based on specific requirements.
Dry contact input for speed switching
The controller utilizes a dry contact input to switch between the selected fan speeds while the motor is active. For instance, an external clock or timer can be used to trigger the switches, enabling high speed during the day and low speed during the night based on the desired schedule.
TK monitoring contacts
TK monitoring is a method used for thermal motor protection in certain motor control systems. It involves monitoring thermal motor contacts (TK) that measure the temperature in the motor windings. If the motor overheats, the TK monitoring function is designed to take action to protect the motor from damage. Some motors are equipped with special thermal motor contacts (TK) incorporated in the motor windings. These contacts are designed to detect the temperature of the motor. The TK terminals on the controller are used to connect the thermal motor contacts from the motor to the controller. The controller includes a monitoring circuit that continuously measures the resistance or voltage across the TK terminals. This monitoring circuit is designed to interpret the signal received from the thermal motor contacts and determine the motor temperature based on that signal.
In cases where the motor does not have built-in thermal motor contacts, the controller may provide bridge terminals for the TK circuit. These bridge terminals are used to simulate normal motor temperature and enable the TK monitoring function. The bridge should be installed as per the controller's instructions to ensure proper operation.
Two start / stop contacts for remote ON / OFF switching
The controller includes two start/stop contacts that allow for remote ON/OFF switching of the fan motor. These contacts provide the capability to enable or disable the motor from a remote location. The remote switch can be a push button, a toggle switch, or any other suitable control device. Ensure that the remote switch is compatible with the voltage and current ratings specified for the start/stop contacts.
Alarm output
In case of motor problems, such as overheating, an alarm output (230 VAC) is activated. This output can generate alerts or control warning indications, allowing prompt detection and response to motor issues. If the motor overheats, the TK monitoring function will disable the motor to prevent further damage.
Single phase, 230 VAC unregulated output
The controller features 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 is closed, and when the fan motor is active, the damper is opened. This allows coordinated control of associated equipment based on the fan motor status.
Auto reset after power failure
In the event of a power failure, the controller has an automatic reset feature. When power is restored, the controller will reset itself, and the fan motor will restart automatically. This ensures seamless operation and eliminates the need for manual intervention after power disruptions.
For high speeds, the available voltages are 210, 250, 290, 330, and 400 VAC, whilst for low speeds, the options are 130, 170, 210, 250, and 290 VAC. These voltage settings can be switched using a dry contact input while the motor is active.
By utilizing the SC2A4 series, you can easily and flexibly control the fan speeds to meet specific requirements at different times of the day or for different applications.
Two-step fan speed selection
The controller includes two separate 5-step rotary switches that allow you to select two optimal fan speeds. These speeds can be customized for different scenarios, such as high speed during the day and low speed during the night. This enables energy efficiency and tailored fan performance based on specific requirements.
Dry contact input for speed switching
The controller utilizes a dry contact input to switch between the selected fan speeds while the motor is active. For instance, an external clock or timer can be used to trigger the switches, enabling high speed during the day and low speed during the night based on the desired schedule.
TK monitoring contacts
TK monitoring is a method used for thermal motor protection in certain motor control systems. It involves monitoring thermal motor contacts (TK) that measure the temperature in the motor windings. If the motor overheats, the TK monitoring function is designed to take action to protect the motor from damage. Some motors are equipped with special thermal motor contacts (TK) incorporated in the motor windings. These contacts are designed to detect the temperature of the motor. The TK terminals on the controller are used to connect the thermal motor contacts from the motor to the controller. The controller includes a monitoring circuit that continuously measures the resistance or voltage across the TK terminals. This monitoring circuit is designed to interpret the signal received from the thermal motor contacts and determine the motor temperature based on that signal.
In cases where the motor does not have built-in thermal motor contacts, the controller may provide bridge terminals for the TK circuit. These bridge terminals are used to simulate normal motor temperature and enable the TK monitoring function. The bridge should be installed as per the controller's instructions to ensure proper operation.
Two start / stop contacts for remote ON / OFF switching
The controller includes two start/stop contacts that allow for remote ON/OFF switching of the fan motor. These contacts provide the capability to enable or disable the motor from a remote location. The remote switch can be a push button, a toggle switch, or any other suitable control device. Ensure that the remote switch is compatible with the voltage and current ratings specified for the start/stop contacts.
Alarm output
In case of motor problems, such as overheating, an alarm output (230 VAC) is activated. This output can generate alerts or control warning indications, allowing prompt detection and response to motor issues. If the motor overheats, the TK monitoring function will disable the motor to prevent further damage.
Single phase, 230 VAC unregulated output
The controller features 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 is closed, and when the fan motor is active, the damper is opened. This allows coordinated control of associated equipment based on the fan motor status.
Auto reset after power failure
In the event of a power failure, the controller has an automatic reset feature. When power is restored, the controller will reset itself, and the fan motor will restart automatically. This ensures seamless operation and eliminates the need for manual intervention after power disruptions.
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