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  • New item   Overload and Phase Asymmetry Protection Relay | Motor Protection | 3-12A | 0.1-20s | 150-260VAC | DIN Rail
    New item   Overload and Phase Asymmetry Protection Relay | Motor Protection | 3-12A | 0.1-20s | 150-260VAC | DIN Rail 1
    New item   Overload and Phase Asymmetry Protection Relay | Motor Protection | 3-12A | 0.1-20s | 150-260VAC | DIN Rail 2
    New item   Overload and Phase Asymmetry Protection Relay | Motor Protection | 3-12A | 0.1-20s | 150-260VAC | DIN Rail 3

    Overload and Phase Asymmetry Protection Relay | Motor Protection | 3-12A | 0.1-20s | 150-260VAC | DIN Rail

    Code: ES-TRM-12
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    Price 53.98 € VAT incl.
    ( 44.61 € VAT excl. )
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    Digital overload and phase asymmetry relay designed to protect electric motors, pumps, and other three-phase equipment against overcurrent and phase imbalance. Operates within a 150–260 V AC range, with adjustable overload current from 3–12 A and trip delay from 0.1–20 s. The relay provides ±1% current and time accuracy, features 50% phase asymmetry monitoring, and supports manual, semi-automatic, and automatic reset modes. Designed for 35 mm DIN rail mounting, with relay contact capacity up to 5 A / 250 V AC. 

  • Product description
    Digital Overload and Phase Asymmetry Controller | 150-260VAC | DIN Rail | 0.1-3A

    Digital Overload and Phase Asymmetry Relay | 150-260 VAC | Precise Current and Phase Monitoring

    Digital overload controller – is a professional protection device designed to protect electrical loads (motors, pumps) against damage caused by overcurrent while providing convenient system control and monitoring. The device offers very high accuracy (current and time error of only ±1%), adjustable trip delay (0.1 – 20s), and fixed phase asymmetry monitoring. 

    Comprehensive protection against overcurrent and phase imbalance

    The device allows precise adjustment of the overload threshold (3-12A) and trip delay (0.1-20s). It also provides 50% phase asymmetry monitoring and three different reset modes: manual, semi-automatic, and automatic. 

    150 – 260V AC
    Operating voltage
    3 – 12A
    Overload adjustment range
    0.1 – 20s 
    Trip delay 
    ±1% 
    Measurement and timing accuracy 

    Operating principle and functions

    Function / Block Parameters / Modes Description / Purpose in the System
    Overload monitoring (A>) Adjustable by knob (3 – 12A),  accuracy ±1% 

    If the current exceeds the set value, the device accurately detects the overload and begins counting the delay time. 
    Trip delay Adjustable (0.1 – 20s), accuracy ±1%  Allows the response time to be adapted while ignoring short-term, non-hazardous current surges.
    Start-up delay Fixed 5-second delay Prevents false current triggering during device or motor start-up. 
    Phase asymmetry Fixed 50% difference threshold (responds within 2s) Protects motors against phase loss or significant voltage / current imbalance.
    Reset modes Manual, semi-automatic, automatic Selected by pressing and holding the SELECT button and can be adapted to the requirements of the controlled equipment.

    How does the controller work?

    1. Connect the device wiring according to the wiring diagram and switch on the power supply (the display shows the configured values for 5 seconds).
    2. Use the „A>“ knob to set the required overload current threshold and the „t“ knob to set the trip delay time (from 0.1 to 20 seconds). 
    3. When the device is switched on, the relay activates, the contact switches to terminal 3, and the „OUT“ LED lights up.
    4. If the current exceeds the set threshold, the „ERR“ LED lights up and, after the delay time has elapsed, the relay switches off (the contact switches to terminal 1).
    5. If a current difference greater than 50% is detected between the phases, a phase asymmetry fault is registered within 2 seconds, the corresponding phase display flashes, and the fault LED lights up.
    Selecting the reset mode

    Press and hold the SELECT button for 10 seconds to change the mode: Manual mode (requires pressing the Reset button), Semi-automatic mode (automatically resets 3 times), or Automatic mode (the system resets automatically).

    Technical specifications

    Operating voltage (Un) 150V – 260V AC
    Frequency and power consumption 50/60Hz | Operating power <6VA
    Overload current 3 – 12A adjustable range
    Trip delay  0.1 – 20 seconds (adjustable) 
    Measurement and timing accuracy  Current: ± 1% | Time: ± 1% 
    Phase asymmetry 50% (fixed)
    Contacts and load 5A / 250V AC (resistive load)
    Display and indicators 3x3-digit display, 5 LED indicators
    Cable cross-section and installation Cable up to 2.5 mm² | Mounting on a 35 mm DIN rail
    Operating temperature and altitude -20°C ~ +55°C | Altitude above sea level <2000m
    Weight 290g

    Advantages / Benefits

    • High accuracy: industrial-grade ±1% accuracy for current and time measurements.
    • Flexible delay setting: adjustable trip time (up to 20s) allows the protection to be precisely matched to the motor characteristics.
    • Dual protection: effectively protects against overcurrent and dangerous phase imbalance.
    • Flexible control: three Reset modes and a clear 3x3-digit display. 

    Disadvantages / Limitations

    • Limited current range: this model is designed for medium-current circuits (3 – 12A). Higher loads require other models or additional current transformers.
    • Fixed asymmetry threshold: the phase asymmetry threshold is fixed at 50% and cannot be adjusted according to the user's requirements.
    • Not suitable for humid environments: the device must not be operated in environments exposed to moisture or aggressive chemicals.
    • Relay contact limitation: the output contact is rated for up to 5A / 250VAC resistive load; therefore, an additional contactor is required for direct control of higher-power motors.

    What is it suitable for? (Applications)

    • Protection of electric motors and pumps against overload
    • Industrial control cabinets and automation systems requiring accurate monitoring 
    • Industrial equipment requiring phase asymmetry monitoring

    What is it not suitable for?

    • Continuous operation in humid or aggressive chemical environments
    • High-power circuits exceeding the specified current and contact ratings

    Practical example

    A three-phase pump operates on a production line and requires continuous protection against current overload and phase loss. This digital overload controller is installed in the control panel. After setting the overload threshold to 3-12A and selecting the semi-automatic reset mode, the device monitors the operation of the pump. If the pump becomes jammed and the current rises above the configured threshold, the controller waits for the set delay time, switches off the relay, and protects the motor against overheating and damage.

    Frequently Asked Questions (FAQ)

    What is the operating voltage of this controller?

    The device operates within a voltage range of 150V – 260V AC.

    How do I change the device's Reset mode?

    Press and hold the SELECT button for 10 seconds until the mode LED indication changes.

    Can the trip delay be adjusted? 

    Yes, the trip delay can be adjusted within a range of 0.1 to 20 seconds. 

    Does the device provide protection against phase asymmetry?

    Yes. If the difference between phase currents exceeds 50%, the device detects a phase asymmetry fault within 2 seconds.

    Important safety note for the installer

    When installing the device in a distribution panel, make sure that a separate nearby power disconnect switch and protective circuit breaker are provided so that the operator can quickly disconnect the device in an emergency.

    Digital overload and phase asymmetry controller – is a highly accurate solution for protecting valuable equipment against failures caused by overcurrent and phase imbalance.

    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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