.webp "Transformer fan speed controller clock")
.webp "Fan speed controller week timer")
.webp "5 speed controller week timer")
.webp "Fan speed controller calendar")
.webp "Programmable 5 speed controller AC fan")
.webp "Fan speed controller week calendar")
EU declaration conformity
Three phase fan speed controller | calendar function | 2,5 A
Product description
This transfomer fan speed controller is intended for three-phase 400 V motors and has a built-in calendar function which can be used for configuring the fan parameters a year ahead.
The (combined) maximum current is 2,5 A. Two optimal motor speeds can be selected. It can be configured to switch between two optimal speeds using the day-week programming functionality.
AC fan speed is regulated by reducing motor voltage via autotransformer technology. This technology generates a motor voltage with perfect sinusoidal shape, guaranteeing quiet motor operation.
TK monitoring function deactivates the motor in case of overheating.
After a power failure, the motor will automatically restart.
The enclosure is surface mountable indoors (IP54).
The supply voltage is 400 VAC.
Additional specifications and description
The series
The ST2R4 is a speed controller designed for three-phase 400 V motors. It provides various advanced features, including thermal protection, alarm outputs and automatic restart, making it suitable for a wide range of applications. It is specifically designed for controlling the rotational speed of voltage-controllable motors.
Thanks to the built-in clock these transformer controllers can work completely autonomously. When commissioning, two speeds (high and low) can be selected out of 0-130-170-210-250-290-330-400 V. High and low speed operation time ranges can be set in the clock together with a range of motor stop (day/week program). Thus the ideal control over a prolonged period is achieved, eliminating the need for frequent settings.
Operating modes
The ST2R4 controller has four operating modes:
STAND-BY: the motor is not working (due to clock setting)
STOPPED: the motor is not working (the controller is stopped by pressing the I/O button or a TK alarm condition occurred)
AUTO: the motor speed depends on the real time clock setting (High Mode/Low Mode/Standby)
MANUAL: the controller enters high mode by pressing the UP button and low mode by pressing DOWN button.
The operating modes can be changed using the real time clock functionality or the buttons on the enclosure.
Also, user and installer passwords can be set, thus allowing easy and safe control over the controller.
Extra features
Calendar function: The ST2R4 speed controller features a built-in weekly timer, enabling speed switching between two predefined levels. Utilizing the integrated clock, this transformer controller can autonomously regulate the electric motor based on the time of day and night. Mode selection and precise adjustments are done via the LCD display and keyboard on the ST2R4 enclosure.
Remote control start and stop: The ST2R4 transformer speed controller is equipped with one normally open and one normally closed contact, facilitating remote initiation and deactivation of the controller. These contacts can also serve to monitor its operational status. Connected equipment such as indication and warning devices, thermostats, and temperature relays can be used in conjunction with these contacts.
USB type B connector for settings via a PC: The ST2R4 fan speed controller features a USB type B connector, employed for reading, inputting, and modifying all available controller parameters using your computer. Accessing the setup requires the use of the 3SM Center software developed by Sentera, which can be downloaded for free from the website.
Unregulated output: The ST2R4 speed controller has an additional unregulated output at 230 V, which is activated when the electric motor is in operation. This output features two positions: closed (230 V) and open (0 V). The maximum current for this output should not exceed 2 A. An example of its application is the control of an electric actuator for air or water valves. When the fan is activated, the valve opens, and upon deactivation, it closes. Additionally, if remote monitoring of the controller operation is required, a lamp can be connected to the unregulated output.
Automatic power-on after power failure: Considering the potential for power interruptions when working with electrical equipment, the fan speed controller and motor will automatically restart once the power is restored following an outage.
Alarm output: The ST2R4 speed controller includes an unregulated alarm output (230 VAC), which activates in response to a thermal protection event that opens the thermal contacts safeguarding the electric motor from overheating. This output can be used to connect a lamp or a buzzer.
Motor overheat protection: The ST2R4 fan speed controller is equipped with terminals designed for the connection of the thermal contacts of the electric motor (TK). These thermal contacts serve to measure the temperature of the motor windings. In the event of overheating, the motor is deactivated to mitigate the risk of damage or failure. Following a thermal protection event, manual restart of the speed controller is required. If the motor does not have thermal contacts, the TK terminals must be bridged to simulate normal operation.
Remarks, reviews & ratings