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EU declaration conformity
Fan speed controller 400 V | day-night function | 8 A
Product description
A two-speed controller for 400 V motors with thermal contacts (TK) is provided. The maximum combined motor current is 8 A.
This controller has two distinct 5-step switches that allow you to choose between two different fan speeds. When the motor is turned on, a dry contact input allows you to select between the two speeds.
If the TK monitoring feature detects overheating, it shuts the motor. After a power outage, the motor will resume automatically.
External devices can be controlled by the alarm and unregulated outputs to create alerts or validate normal operation.
The fan speed is controlled by lowering the voltage of the motor using autotransformers. This technology generates an output voltage with perfect sinusoidal shape, guaranteeing quiet motor operation.
The enclosure is surface-mountable and provides IP54 protection against dirt, dust, and moisture entry.
The supply voltage is 400 VAC
Additional specifications and description
Working principle
The operation of the SC2A4 fan speed controller utilizes built-in autotransformers, which feature stepwise control of the voltage applied to the electric motor, allowing to change the speed of the fan. This technology is very reliable and durable. Autotransformers also have a special impregnation to reduce the level of electrical noise created. The output voltage generated by the controller has the form of a pure sinusoid, which ensures quiet operation of the electric motor and increases its service life. Even though the controller itself might produce some noise, the motor of the fan operates extremely quietly and, therefore ,it is suitable for noise-sensitive environments.
Two modes of operation with different rotation speeds
The SC2A4 transformer fan speed regulator features two five-step output power switches. Thus, it is possible to select "high" and "low" fan speed. Switching between them is carried out through an additional dry contact. One of the options for using this contact is the connection of an external clock, which makes it possible to work in the «day-night» mode.
Remote start and stop control
The SC2A4 has one normally open and one normally closed contact. They can be used for remote switching on and off of the controller, as well as for monitoring its operation. Indications and notifications, thermostats, temperature relays, etc. are used as connected equipment.
Automatic switching on after a power failure
When working with electrical equipment, always be aware of possible power failures. In the event of such a failure, after the power is restored, the speed controller and the electric motor will be restarted automatically.
Alarm signal
The SC2A4 is equipped with a non-regulated alarm output (230 V, 1 A) that warns of a possible issue. It is active when the thermal contacts that protect the electric motor from overheating are opened. This output can be used to connect a lamp or an audible alarm.
Extra non-regulated output
The controller is equipped with an additional unregulated output (230 VAC), which remains powered in standby mode. It is called "unregulated" because it has only two positions - on (230 V) and off (0 V). The maximum current for this output should not exceed 2 A. One examples of using this output is controlling an electric actuator of an air or water valve. When the fan is turned on, the valve opens, and when it is turned off, it closes.
Overheating protection of the electric motor
The fan speed regulator SC2A4 is equipped with terminals for connecting thermocontacts of the electric motor (TK). Thermocontacts are used to measure the temperature on the windings of the electric motor. In case of overheating, the electric motor will be stopped to eliminate the risk of damage or failure. After the overheating protection is activated, the speed controller is restarted manually. If the motor is not equipped with thermal contacts, the TK terminals must be connected to each other to simulate its normal operation.
LED indication
The fan speed controller is equipped with LED indicators located on the door of the enclosure. When power is connected to the transformer controller, the indicator lights up in green. When the overheat protection of the electric motor is activated, the red indicator lights up.
Housing
The main purpose of the housing is to protect the internal part of the controller from external contamination and moisture, as well as from adverse environmental factors. Sentera carefully monitors the quality of the manufactured and supplied products, both in the electrical and non-electrical parts. The enclosure of the SC2A4 is made of sheet steel with a protective paint coating and provides reliable protection against mechanical and other influences. It is certified according to the European standard EN 62208 and has IP54 protection against dust and moisture. To ensure optimum reliable and safe operation, as well as to exclude the possibility of overheating, the controller must be installed in a cool place without direct sunlight. Ambient operating temperature must be in the range from -20 to +35 °С, and the relative humidity is from 5 to 95%. Condensation must be avoided.
The operation of the SC2A4 fan speed controller utilizes built-in autotransformers, which feature stepwise control of the voltage applied to the electric motor, allowing to change the speed of the fan. This technology is very reliable and durable. Autotransformers also have a special impregnation to reduce the level of electrical noise created. The output voltage generated by the controller has the form of a pure sinusoid, which ensures quiet operation of the electric motor and increases its service life. Even though the controller itself might produce some noise, the motor of the fan operates extremely quietly and, therefore ,it is suitable for noise-sensitive environments.
Two modes of operation with different rotation speeds
The SC2A4 transformer fan speed regulator features two five-step output power switches. Thus, it is possible to select "high" and "low" fan speed. Switching between them is carried out through an additional dry contact. One of the options for using this contact is the connection of an external clock, which makes it possible to work in the «day-night» mode.
Remote start and stop control
The SC2A4 has one normally open and one normally closed contact. They can be used for remote switching on and off of the controller, as well as for monitoring its operation. Indications and notifications, thermostats, temperature relays, etc. are used as connected equipment.
Automatic switching on after a power failure
When working with electrical equipment, always be aware of possible power failures. In the event of such a failure, after the power is restored, the speed controller and the electric motor will be restarted automatically.
Alarm signal
The SC2A4 is equipped with a non-regulated alarm output (230 V, 1 A) that warns of a possible issue. It is active when the thermal contacts that protect the electric motor from overheating are opened. This output can be used to connect a lamp or an audible alarm.
Extra non-regulated output
The controller is equipped with an additional unregulated output (230 VAC), which remains powered in standby mode. It is called "unregulated" because it has only two positions - on (230 V) and off (0 V). The maximum current for this output should not exceed 2 A. One examples of using this output is controlling an electric actuator of an air or water valve. When the fan is turned on, the valve opens, and when it is turned off, it closes.
Overheating protection of the electric motor
The fan speed regulator SC2A4 is equipped with terminals for connecting thermocontacts of the electric motor (TK). Thermocontacts are used to measure the temperature on the windings of the electric motor. In case of overheating, the electric motor will be stopped to eliminate the risk of damage or failure. After the overheating protection is activated, the speed controller is restarted manually. If the motor is not equipped with thermal contacts, the TK terminals must be connected to each other to simulate its normal operation.
LED indication
The fan speed controller is equipped with LED indicators located on the door of the enclosure. When power is connected to the transformer controller, the indicator lights up in green. When the overheat protection of the electric motor is activated, the red indicator lights up.
Housing
The main purpose of the housing is to protect the internal part of the controller from external contamination and moisture, as well as from adverse environmental factors. Sentera carefully monitors the quality of the manufactured and supplied products, both in the electrical and non-electrical parts. The enclosure of the SC2A4 is made of sheet steel with a protective paint coating and provides reliable protection against mechanical and other influences. It is certified according to the European standard EN 62208 and has IP54 protection against dust and moisture. To ensure optimum reliable and safe operation, as well as to exclude the possibility of overheating, the controller must be installed in a cool place without direct sunlight. Ambient operating temperature must be in the range from -20 to +35 °С, and the relative humidity is from 5 to 95%. Condensation must be avoided.
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