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  • New item   -578.14€Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40
    New item   -578.14€Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40 1
    New item   -578.14€Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40 2
    New item   -578.14€Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40 3
    New item   -578.14€Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40 4

    Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40

    Code: STVS4-80L40
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  • Product description

    Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40

    STVS4-80L40 – Sentera Controls transformer speed controller for three-phase 400 VAC fan motors up to 8 A, controlled by an analogue 0-10 VDC signal (galvanically isolated input). 5 steps, sinusoidal voltage, TK terminals.

    Key idea:
    The quietness of a transformer with the convenience of automation: the step is selected by a sensor, controller or BMS via a 0-10 VDC signal, or by an external potentiometer. The motor receives sinusoidal voltage, and the TK status is transmitted via a digital 12 VDC output.
    What it is for STVS4-80L40:
    This model is intended for high-power fans (up to 8 A) – industrial fans in production halls, warehouses, farm buildings or a larger group of fans.
    Max. motor current
    8 A
    Control
    0-10 VDC (isolated) / potentiometer
    Motor protection
    TK + status output 12 VDC
    Supply / protection
    3×400 VAC + N; IP54

    Operating principle

    The controller is wall-mounted. The 3×400 VAC supply is connected to R, S, T and N, the motor – to U, V, W, the thermal contacts – to TK, the control signal – to V/C and 0V, and the unregulated 230 VAC output – L1, N1.

    The controller is based on an autotransformer with several taps (steps). According to the control signal the motor is switched to another tap, so the output voltage changes in steps rather than steplessly. Output voltages: 0 – 130 – 180 – 230 – 300 – 400 VAC. The steps are switched on with a rising signal at 2, 4, 6, 8 and 9.5 VDC; with a falling signal – 0.2 VDC lower (hysteresis prevents “hunting” between steps).

    The output voltage is SINUSOIDAL – without phase cutting as in electronic controllers. Therefore the motor runs quietly even at low speed, does not heat up due to higher harmonics and does not interfere with other equipment. This is the solution for motors that hum or buzz when controlled by an electronic controller.

    For manual control, an external potentiometer (e.g. Sentera MTP-X10K-NA) supplied from the +12 VDC output can be connected. The digital 12 VDC output indicates the TK status: 0 VDC – TK fault, 12 VDC – normal operation. Engineer's note: reducing the voltage of an AC asynchronous motor increases slip, so less energy is saved than with an EC fan or frequency inverter. The strength of a transformer speed controller is reliability, quietness and simplicity, not maximum efficiency.

    Benefits STVS4-80L40?
    The only transformer controller in this group with analogue control: quiet sinusoidal motor operation and automatic step selection based on a sensor or BMS.

    Technical specifications

    Product type Transformer three-phase fan motor speed controller with 0-10 VDC control
    Manufacturer / code Sentera Controls / STVS4-80L40
    Series STVS4 (1.5 / 2.5 / 4 / 6 / 8 / 11 A)
    Supply voltage 3×400 VAC, 50–60 Hz, with neutral (R, S, T, N)
    Max. motor current 8 A
    Regulated output (U, V, W) 0 – 130 – 180 – 230 – 300 – 400 VAC (positions 0–5), sinusoidal voltage
    Analogue input (V/C) 0-10 VDC, galvanically isolated; or external potentiometer (MTV / MTP)
    Step switching thresholds Rising: 2 / 4 / 6 / 8 / 9.5 VDC; falling: 0.2 VDC lower
    Unregulated output (L1, N1) 230 VAC, max. 2 A
    Supply outputs (+12V, +V) 12 VDC, max. 50 mA each, no more than 100 mA in total
    Digital output 12 VDC, max. 50 mA: 0 VDC – TK fault, 12 VDC – normal operation
    Motor protection TK terminals for motor thermal contacts
    Indication Green LED – device switched on
    Housing Metal, powder-coated RAL 7035
    Protection class IP54 (EN 60529), for indoor use only
    Operating environment -20…+35 °C, 5–95 % rH non-condensing
    Dimensions A 400 / B 425 / C 200 / D 355 / E 355 mm (letter meanings – according to the datasheet drawing)
    Packaging (L × W × H) 445×410×255 mm
    Weight 33.05 kg (net)
    Compliance LVD 2014/35/EU, EMC 2014/30/EU (EN 61326), WEEE 2012/19/EU, RoHS 2011/65/EU

    Manufacturer documentation

    ✔ Recommended by Elektrotechnikos sprendimai

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

    Main functions

    • Analogue 0-10 VDC control – the step is selected by a sensor, controller or BMS; the input is galvanically isolated.
    • Hysteresis 0.2 VDC – stable operation without frequent step switching.
    • +12 VDC outputs – supply for an external potentiometer or sensor (up to 50 mA each).
    • TK and status output – connection of motor thermal contacts and a 12 VDC signal for the automation system.
    • Sinusoidal output voltage – quiet motor operation at all steps.
    • Unregulated 230 VAC output (2 A) – for a damper actuator or valve.

    Where is it used?

    • Automated ventilation systems with three-phase AC fans
    • Production and storage premises with temperature or CO₂ control
    • Sites with BMS and 0-10 VDC control
    • Ventilation of agricultural buildings controlled by a climate controller

    On-demand operation

    For the automation integrator.
    Standard 0-10 VDC input and 12 VDC status output – easy integration into a controller or BMS.
    For the electrician.
    TK, signal and power circuits are connected to a single device.
    For the building owner.
    Ventilation adapts to demand, and the motor runs quietly.

    Application guide: how it is used in practice

    Typical STVS4-80L40 applications:

    Site What is connected Result Installer's note
    Production hall Temperature controller 0-10 VDC → V/C, 0V On a hot day the fan is switched to a higher step Thresholds: 2 / 4 / 6 / 8 / 9.5 VDC
    Building with BMS BMS analogue output → V/C; digital output → BMS input The step is controlled centrally, the TK status is visible in the BMS Digital output – 12 VDC, up to 50 mA
    Manual control from another room MTP-X10K-NA potentiometer → +12V / V/C / 0V The operator selects the step with a remote potentiometer +12V and +V combined load – up to 100 mA
    Fan with damper Damper actuator 230 VAC → L1, N1 The damper is powered together with the fan 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 STVS4-15L40 (1.5 A)
    1.5–2.5 A STVS4-25L40 (2.5 A)
    2.5–4 A STVS4-40L40 (4 A)
    4–6 A STVS4-60L40 (6 A)
    6–8 A STVS4-80L40 (8 A) ← this model
    8–11 A STVS4110L40 (11 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. Choose a margin if the motor current is close to the model's limit or the fan often runs at the maximum step.
    When to choose another solution: for manual control – STR-4 or STRS4 (with TK); with NO/NC inputs and alarm – STRA4 or STTA4; for two clock-controlled speeds – SC2A4 or ST2R4; for stepless control – an EC fan or a frequency inverter.

    Pros

    • Analogue 0-10 VDC control (galvanically isolated)
    • Sinusoidal output voltage
    • TK terminals and 12 VDC status output
    • +12 VDC supply for potentiometer
    • Unregulated 230 VAC output (2 A)
    • Metal IP54 enclosure

    Cons / limitations

    • The signal is converted into 5 steps – there is no stepless speed change
    • No knob on the enclosure – an external potentiometer is required for manual control
    • No Modbus communication
    • Step (not stepless) control – the speed is selected from fixed voltages
    • Heavy weight and large dimensions compared with electronic controllers
    • Indoor use only, operating temperature up to +35 °C
    • Not suitable for EC fans and motors controlled by a frequency inverter

    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).
    • Check that the motor is suitable for voltage control and that its rated current does not exceed 8 A.
    • The supply requires a neutral (N).
    • Route control signal cables separately from power cables.
    • The device is heavy – fix it to a load-bearing wall or structure using suitable fixings.
    • For indoor use only (-20…+35 °C, non-condensing); leave space for cooling.

    Quick selection guide

    8 A
    3×400 VAC
    0-10 VDC
    TK
    5 steps
    IP54
    Suitable when you need:
    • a three-phase fan up to 8 A controlled by a sensor, controller or BMS;
    • quiet motor operation with automation;
    • TK status transmission to the automation system.
    Check before use:
    • the control signal type – 0-10 VDC is required;
    • the motor rated current and whether it is voltage-controllable;
    • the installation location (33.05 kg, up to +35 °C).
    Important reminder: STVS4-80L40 converts the signal into 5 steps – this is not stepless control.

    FAQ

    Does the speed change steplessly?
    No, the 0-10 VDC signal selects one of 5 steps (thresholds 2 / 4 / 6 / 8 / 9.5 VDC).
    Can it be controlled manually?
    Yes, by connecting an external potentiometer, e.g. Sentera MTP-X10K-NA.
    Can it be controlled with a 0-20 mA signal?
    The datasheet specifies only a 0-10 VDC input.
    How does the automation learn about a TK fault?
    Digital output: 0 VDC – TK fault, 12 VDC – normal operation.
    What voltages does the motor receive?
    0, 130, 180, 230, 300 and 400 VAC.

    Transformer three-phase fan motor speed controller controlled by analogue signal | TK | 8A | 400VAC | surface-mounted | IP54 | Sentera Controls | STVS4-80L40

    Sentera STVS4-80L40 – transformer speed controller for three-phase fans up to 8 A, controlled by a 0-10 VDC signal, 3×400 VAC, 5 steps, sinusoidal voltage, TK terminals, 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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