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  • New item   -154.51€Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22
    New item   -154.51€Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22 1
    New item   -154.51€Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22 2
    New item   -154.51€Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22 3
    New item   -154.51€Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22 4

    Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22

    Code: SER-1-75L22
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  • Product description

    Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22

    SER-1-75L22 – Sentera Controls transformer fan speed controller with a red emergency button for single-phase AC motors up to 7.5 A. For everyday use the speed is selected with a 5-position knob, and when the emergency (or external) button is pressed the fan switches on at maximum speed for smoke extraction.

    Key idea:
    Normal quiet ventilation control and rapid smoke extraction at the push of a button – e.g. in a kitchen, smoking room or workshop. SER-1-75L22 is intended for more powerful fans or several fans together (up to 7.5 A).
    What it is for SER-1-75L22:
    This model is intended for high-power fans (up to 7.5 A) – industrial fans in production halls, warehouses, farm buildings or a larger group of fans.
    Max. motor current
    7.5 A
    Control
    5-step knob + emergency button
    Emergency mode
    Maximum speed (230 VAC)
    Protection
    IP54, surface mounting

    Operating principle

    The 230 VAC supply (L, N, PE) and the motor to the regulated output (U, N) are connected; the unregulated L1 output (230 VAC, 2 A) – for a damper or auxiliary device. An external button with a normally open (NO) contact can be connected to the RB terminals.

    Inside is an autotransformer with several output taps. Each step supplies the motor with a different preset voltage: 0-80-110-140-170-(190)-230 VAC. Control is stepped, not stepless – speed changes in fixed increments. In knob positions 1–5 the output is 80, 110, 140, 170 and 230 VAC; in position 0 the motor and L1 are switched off. The 190 V tap is present but not connected; other voltages can be selected by changing the wiring.

    When the red emergency button on the enclosure or an external button connected to RB is pressed, the fan switches on at maximum speed – the room is quickly cleared of smoke.

    The output voltage is sinusoidal because it is obtained by a transformer rather than by electronically “chopping” the sine wave. Therefore the motor runs quietly, heats up less and does not hum – the transformer speed controller is also suitable for AC motors that audibly hum at low speed with an electronic (triac) controller. Engineer's note: the speed of an AC asynchronous motor is reduced by increasing slip, so less energy is saved than with an EC fan or frequency inverter. The greatest advantage of transformer control is quiet and reliable motor operation at all steps.

    Benefits SER-1-75L22?
    Everyday quiet ventilation control and maximum extraction with one button – without additional contactors or relays.

    Technical specifications

    Product type Transformer fan speed controller with emergency (smoke extraction) button
    Manufacturer / code Sentera Controls / SER-1-75L22
    Series SER-1 (3.5 / 5 / 7.5 A)
    Supply voltage 230 VAC, 50–60 Hz
    Max. motor current 7.5 A
    Regulated output (U, N) 0-80-110-140-170-(190)-230 VAC, sinusoidal voltage (190 V – not connected)
    Unregulated output (L1) 230 VAC, 2 A (off in position 0)
    Control 5-step knob with OFF position
    Emergency mode Red button on the enclosure – maximum fan speed
    External button input (RB) Normally open (NO) contact
    Indication Green LED – device switched on
    Fuse T-12.5 A-H, 5×20 mm
    Housing ABS plastic, UL94-V0, grey RAL 7035
    Protection class IP54 (EN 60529), for indoor use only
    Operating environment -20…+35 °C, 5–95 % rH non-condensing
    Dimensions A / B / C / D / E 200 / 305 / 155 / 183 / 236 mm (according to the datasheet drawing)
    Weight 8.50 kg net / 8.90 kg gross
    Packaging dimensions 320×210×160 mm
    Compliance LVD 2014/35/EU, EMC 2014/30/EU (EN 61326), RoHS 2011/65/EU, WEEE 2012/19/EU

    Manufacturer documentation

    ✔ Recommended by Elektrotechnikos sprendimai

    Original manufacturer documentation – technical data, wiring diagrams and installation instructions.

    Main functions

    • Red emergency button – a single press switches the fan to maximum speed.
    • External button input RB (NO) – emergency mode can also be activated from another location.
    • 5 speed steps and OFF – everyday ventilation control with the knob.
    • Sinusoidal output voltage – quiet motor operation.
    • Unregulated L1 output (2 A) – for a damper actuator or other device.

    Where is it used?

    • Kitchens, cafés, restaurants
    • Smoking and break rooms
    • Workshops (welding, melting fumes)
    • Garages and technical rooms
    • Fans with single-phase AC motors

    On-demand operation

    For the electrician.
    Emergency mode without additional contactors; external button – directly to RB.
    For the ventilation installer.
    Quiet stepped control and rapid maximum extraction in one device.
    For the user.
    Clear knob and red button – intuitive.

    Application guide: how it is used in practice

    Typical SER-1-75L22 applications:

    Site What is connected Result Installer's note
    Kitchen or café Extract fan → U, N Everyday – the required speed, when food is burnt – maximum with one button Motor rated current ≤ 7.5 A
    Smoking room External button by the door → RB Smoke is removed quickly, the button is conveniently accessible Use an NO contact button
    Welding workshops Fan → U, N; damper → L1 Maximum extraction during welding L1 load – up to 2 A
    Garage Fan → U, N After the motor starts – rapid air purge The controller is intended for indoor use only

    How to select the controller current

    Rated current of the motor(s) Recommended model
    up to 3.5 A SER-1-35L22 (3.5 A)
    3.5–5 A SER-1-50L22 (5 A)
    5–7.5 A SER-1-75L22 (7.5 A) ← this model
    Rule: controller max. current ≥ motor rated current (see the motor nameplate). When connecting several fans – motors of the same type – add up their rated currents.
    When to choose another solution: no emergency button needed – STR-1; TK and automatic restart – STRA1; control by a 0-10 VDC signal – STVS1; Modbus RTU – RTVS8; speed switching by an external switch – RTR-1; for a three-phase motor – STR-4.

    Pros

    • Red emergency button – maximum speed
    • External NO button input (RB)
    • Sinusoidal output voltage – quiet operation
    • 5 speed steps and OFF
    • Unregulated L1 output (2 A)
    • IP54 enclosure

    Cons / limitations

    • Step control, not stepless
    • The datasheet does not state compliance with fire smoke extraction system standards – this is not certified fire safety equipment
    • No TK protection, 0-10 VDC input or Modbus
    • Higher weight than electronic controllers (8.50 kg net)
    • Single-phase AC motors only, indoors only (up to +35 °C)

    Safety and installation notes

    • Installation and connection must be carried out by a qualified electrician with the power disconnected.
    • Always connect the protective earth (PE).
    • The rated current of the motor (or the total of several motors) must not exceed 7.5 A; replace the fuse only with one of the same type and rating.
    • The controller is intended only for single-phase, voltage-controllable AC motors; it is not suitable for EC fans or three-phase motors.
    • The controller is not certified fire smoke extraction equipment – for building fire protection systems apply the solutions specified in the design.
    • Only a normally open (NO) contact button is connected to RB.
    • For indoor use only (-20…+35 °C).

    Quick selection guide

    7.5 A
    230 VAC
    Emergency button
    Sinusoidal voltage
    IP54
    Suitable when you need:
    • quiet stepped AC fan control up to 7.5 A;
    • rapid maximum extraction at the push of a button;
    • connection of an external emergency button.
    Check before use:
    • the motor rated current;
    • whether an external push button (NO contact) is required and where it will be located;
    • whether fire smoke extraction equipment requirements apply on site.
    Important reminder: SER-1-75L22 is a ventilation controller with a maximum speed button, not certified fire protection equipment; it does not control EC fans or three-phase motors.

    FAQ

    What does the red button do?
    Switches the fan to maximum speed – for rapid removal of smoke or odours.
    Can a button be connected at another location?
    Yes, an external push button with a normally open (NO) contact is connected to the RB terminals.
    What are the speed steps?
    In positions 1–5: 80, 110, 140, 170 and 230 VAC; the 190 V tap is present but not connected.
    Is it suitable for a fire smoke extraction system?
    The datasheet does not state such compliance – for fire safety systems use the certified equipment specified in the design.
    Can several fans be connected?
    Yes, provided their total rated current does not exceed 7.5 A.

    Transformer fan speed controller with emergency button | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | SER-1-75L22

    Sentera SER-1-75L22 – transformer fan speed controller with emergency smoke extraction button up to 7.5 A, 230 VAC, 5 steps, external button input, sinusoidal voltage, IP54.

    Illustrative image may have been created using AI. The appearance of the product may differ slightly from the image shown. Please refer to the technical specification.

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