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  • New item   -202.84€Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22
    New item   -202.84€Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22 1
    New item   -202.84€Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22 2

    Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22

    Code: STVS1-75L22
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  • Product description

    Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22

    STVS1-75L22 – Sentera Controls transformer fan speed controller for single-phase AC motors up to 7.5 A, controlled by an analogue 0-10 VDC signal. Depending on the signal level, one of 5 sinusoidal voltage steps (0-(80)-110-140-170-190-230 VAC) is selected automatically, and the TK terminals protect the motor against overheating.

    Key idea:
    The quietness of transformer control with the convenience of automation: the speed is set by a sensor, controller, BMS or potentiometer, while the motor is supplied with sinusoidal voltage and does not hum. STVS1-75L22 is intended for more powerful fans or several fans together (up to 7.5 A).
    What it is for STVS1-75L22:
    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
    0-10 VDC (galvanically isolated)
    Output steps
    0-(80)-110-140-170-190-230 VAC
    Protection
    IP54, TK terminals

    Operating principle

    The 230 VAC supply (L, N, PE), the motor to the regulated output (U, N1), the motor thermal protection contacts to the TK terminals, and the control signal to the V/C and 0V terminals are connected. The unregulated L1 output (230 VAC, max. 2 A) is intended for a damper or auxiliary device.

    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. Steps are selected according to the 0-10 VDC signal: with a rising signal, switching occurs at 2, 4, 6, 8 and 9.5 VDC, with a falling signal 0.2 VDC lower (the hysteresis prevents “hunting” between steps). The 80 V tap is present but not connected; other step voltages can be selected by changing the internal wiring.

    Instead of a sensor signal, an external potentiometer can be connected (MTV or MTP, e.g. Sentera MTP-X10K-NA) – a +12 VDC output (max. 50 mA) is provided to supply it. The digital +V output indicates the status: 12 VDC – normal operation, 0 VDC – TK fault. Total current of the +12 V and +V outputs – up to 100 mA.

    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 STVS1-75L22?
    Automatic speed control from any 0-10 VDC source, while retaining the quiet operation of transformer control and motor TK protection.

    Technical specifications

    Product type Transformer fan speed controller controlled by a 0-10 VDC signal
    Manufacturer / code Sentera Controls / STVS1-75L22
    Series STVS1 (1.5 / 2.5 / 3.5 / 5 / 7.5 / 10 / 13 A)
    Supply voltage 230 VAC, 50–60 Hz
    Max. motor current 7.5 A
    Regulated output (U, N1) 0-(80)-110-140-170-190-230 VAC, sinusoidal voltage
    Control input (V/C) 0-10 VDC, galvanically isolated, or external potentiometer (MTV / MTP)
    Switching levels 2 / 4 / 6 / 8 / 9.5 VDC rising; falling – 0.2 VDC lower
    Unregulated output (L1) 230 VAC, max. 2 A
    Auxiliary supply +12 VDC, max. 50 mA (e.g. for MTP-X10K-NA potentiometer)
    Status output (+V) 12 VDC – normal operation, 0 VDC – TK fault; +12 V and +V total up to 100 mA
    Motor thermal protection TK terminals
    Indication Green LED – device switched on
    Fuse T-12.5 A-H, 6×32 mm
    Housing Plastic R-ABS, UL94-V0, grey RAL 7035
    Protection class IP54 (EN 60529), for indoor use only
    Operating environment -20…+35 °C, 5–95 % rH non-condensing
    Weight 7.72 kg net / 7.99 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

    • 0-10 VDC control – the speed is selected automatically by a sensor, controller or BMS.
    • Galvanic isolation – the control circuit is separated from the power circuit.
    • Hysteresis 0.2 VDC – stable operation when the signal fluctuates around a step threshold.
    • TK terminals and +V status output – motor overheating is detected and reported to the automation system.
    • +12 VDC output – an external potentiometer can be supplied without a separate power source.
    • Unregulated L1 output (2 A) – for a damper actuator or other device.

    Where is it used?

    • Ventilation controlled by CO₂, temperature or humidity
    • Buildings with BMS / centralised automation
    • Production, storage and utility premises
    • Fans with motor thermal protection (TK)
    • Sites where quiet operation is important

    On-demand operation

    For the automation engineer.
    Standard 0-10 VDC input with clear switching levels and a status output.
    For the electrician.
    TK, +12 V for a potentiometer and L1 output – directly at the terminals.
    For the ventilation installer.
    Quiet sinusoidal voltage operation without the hum of electronic control.

    Application guide: how it is used in practice

    Typical STVS1-75L22 applications:

    Site What is connected Result Installer's note
    Ventilation based on CO₂ / temperature Sensor 0-10 VDC output → V/C, 0V Speed increases automatically as demand grows Steps switch at 2/4/6/8/9.5 V
    Manual control from another room MTP-X10K-NA potentiometer → +12V, V/C, 0V Speed is selected with a remote potentiometer +12 V output load – up to 50 mA
    BMS integration BMS 0-10 V output → V/C; +V → BMS input BMS controls the speed and receives the TK fault signal +V: 12 V – normal, 0 V – TK fault
    Fan with TK and damper TK contacts → TK; damper → L1 The motor is protected, and the damper operates together with it L1 load – up to 2 A

    How to select the controller current

    Rated current of the motor(s) Recommended model
    up to 1.5 A STVS1-15L22 (1.5 A)
    1.5–2.5 A STVS1-25L22 (2.5 A)
    2.5–3.5 A STVS1-35L22 (3.5 A)
    3.5–5 A STVS1-50L22 (5 A)
    5–7.5 A STVS1-75L22 (7.5 A) ← this model
    7.5–10 A STVS1100L22 (10 A)
    10–13 A STVS1130L22 (13 A)
    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: manual control is sufficient – STR-1; Modbus RTU needed – RTVS8; automatic restart and alarm output – STRA1; stepless electronic control 0-10 VDC / Modbus – EVS-1; for an EC fan – SDP potentiometers; for a three-phase motor – STR-4.

    Pros

    • Sinusoidal output voltage – quiet motor operation
    • Galvanically isolated 0-10 VDC input
    • TK terminals and status output +V
    • +12 VDC output for potentiometer
    • Unregulated L1 output (2 A)
    • IP54 enclosure

    Cons / limitations

    • Step control (5 steps), not stepless
    • Heavy weight and large dimensions (7.72 kg net)
    • No Modbus – for that choose RTVS8
    • Single-phase AC motors only; not suitable for EC fans
    • Operating temperature up to +35 °C, indoor use only

    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.
    • Route control cables (0-10 VDC, +12 V, +V) separately from 230 VAC power cables.
    • Do not exceed the +12 V (50 mA) and the combined +12 V / +V (100 mA) load.
    • For indoor use only (-20…+35 °C).

    Quick selection guide

    7.5 A
    230 VAC
    0-10 VDC
    TK
    Sinusoidal voltage
    IP54
    Suitable when you need:
    • automatic stepped AC fan control up to 7.5 A based on a 0-10 VDC signal;
    • quiet operation without the hum of electronic control;
    • motor thermal protection (TK) with a status signal.
    Check before use:
    • the motor rated current and whether TK contacts are present;
    • the control source signal (0-10 VDC) or the potentiometer type;
    • whether the step voltages 0-(80)-110-140-170-190-230 VAC are suitable.
    Important reminder: STVS1-75L22 does not control EC fans or three-phase motors.

    FAQ

    Does the speed change steplessly according to the 0-10 V signal?
    No, the signal selects one of 5 steps; switching levels – 2, 4, 6, 8 and 9.5 VDC.
    Can it be controlled with a potentiometer?
    Yes, with an external MTV or MTP potentiometer (e.g. MTP-X10K-NA) supplied from the +12 VDC output.
    How does the automation learn about a TK fault?
    Via the +V output: 12 VDC – normal operation, 0 VDC – TK fault.
    Does it have Modbus?
    No. A transformer speed controller with Modbus RTU – RTVS8 series.
    Can several fans be connected?
    Yes, provided their total rated current does not exceed 7.5 A.

    Transformer fan motor speed controller controlled by analogue signal | TK | 7.5A | 230VAC | surface-mounted | IP54 | Sentera Controls | STVS1-75L22

    Sentera STVS1-75L22 – transformer fan speed controller up to 7.5 A, 230 VAC, controlled by a 0-10 VDC signal, 5 steps, TK protection, +12 VDC output for a potentiometer, 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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