Intelligent Motor Protector Phase Failure Relay Overvoltage and Undervoltage Protector Phase Voltage Relay

Quick Detail:

1. voltage monitor，surge protector

2.

• Control for connection of moving equipment(site equipment,agricultural equipent,refrigerated trucks)
• Control for protection of persons and equipment against the consequences of reverse running.
• Normai/emergency power supply switching.
• Protection against the risk of a driving load(phase failure).

Description:

TBT8-A & TBT8-B: Precision Three-Phase Voltage Monitoring Relays for Uncompromising Equipment Protection

In the complex ecosystem of industrial electrical systems, the integrity of the three-phase power supply is paramount. Voltage anomalies—such as asymmetries (phase unbalance), overvoltage, and undervoltage—are not mere inconveniences; they are primary culprits behind motor burnout, drive failure, and catastrophic production downtime. The TBT8-A and TBT8-B Three-Phase Voltage Monitoring Relays are engineered as the first line of defense against these threats. These sophisticated devices provide continuous, precise surveillance of three-phase power lines, automatically disconnecting protected equipment upon detecting hazardous electrical conditions. By ensuring that machinery only operates within safe voltage parameters, they safeguard valuable assets, enhance system reliability, and minimize operational risk.

Dual Model Configuration for Global System Compatibility

The TBT8 series is offered in two distinct models to accommodate the world's most common electrical configurations, ensuring correct application and optimal performance.

• The TBT8-A Model is designed for three-phase wye (star) systems with a neutral conductor. It monitors voltage across phases L1-L2-L3 and the Neutral (N), with its supply voltage derived from a single phase and neutral (L1-N). This model is tailored for lower voltage systems, featuring a phase-to-neutral voltage range from 127V to 265V. It is the ideal solution for a vast array of industrial equipment and facilities operating on 230V/400V wye systems, which are standard across Europe and many other regions.
• The TBT8-B Model is engineered for three-phase delta systems, where a neutral is not typically available for monitoring. It connects directly to the three phase conductors (L1-L2-L3) and is supplied by a voltage between two phases (L1-L2). This model handles higher phase-to-phase voltages, with a broad range from 176V to 552V, making it perfectly suited for 380V/415V/460V delta systems commonly found in heavy industry and specific North American applications.

This clear differentiation allows engineers to select the precise model for their electrical infrastructure, guaranteeing accurate measurement and reliable protection right from the design phase.

Advanced Monitoring and Precision Threshold Control

The core intelligence of the TBT8 relays lies in their highly configurable monitoring capabilities, which go beyond simple under/over-voltage detection.

• Asymmetry (Unbalance) Monitoring: A critical feature for protecting three-phase motors. The TBT8 can detect and respond to voltage unbalance between phases—a condition that causes negative sequence currents, leading to excessive heating and premature motor failure. The asymmetry threshold is independently adjustable from 5% to 15% of the nominal voltage, allowing for fine-tuned protection specific to the sensitivity of the connected equipment.
• Overvoltage and Undervoltage Protection: Users can set the exact voltage trip points for both over and under conditions. The threshold is precisely adjustable within a range of 2% to 20% of the selected nominal voltage (Un). This high degree of adjustability ensures that the relay can be customized for applications with strict tolerances or for systems with known, acceptable voltage fluctuations.
• Integrated Hysteresis and Time Delays: To prevent nuisance tripping during transient events like motor start-ups or short-term grid disturbances, the TBT8 incorporates a 2% hysteresis and an adjustable time delay from 0.1 to 10 seconds. This ensures that the relay only triggers a shutdown if an abnormal condition persists, distinguishing between harmless transients and genuine faults. An additional 0.5s run-up delay at power-up prevents immediate tripping during system initialization.

Robust Output and Assured Operational Reliability

When a fault is detected, the TBT8 acts decisively through a robust Single-Pole, Double-Throw (SPDT) output relay. With a current rating of 10A (AC1), this output is capable of directly controlling the coils of contactors, motor starters, or alarm circuits that manage large power loads. The relay boasts an exceptional mechanical life of 10 million operations and an electrical life (AC1) of 100,000 cycles, underscoring its durability for long-term, demanding industrial use. Clear visual feedback is provided via a green LED for power supply status and a red LED for output activation, enabling quick diagnostics at a glance.

Engineered for Seamless Industrial Integration

Designed with the panel builder in mind, the TBT8 relays feature a compact, 95.5mm x 18mm x 64mm housing that conforms to DIN rail mounting standard EN/IEC 60715. This allows for quick, tool-less installation in any standard control panel. The front panel is rated IP40 for protection against accidental contact, while the terminals are rated IP20. Compliance with Overvoltage Category III and Pollution Degree 2 certifies its suitability for use in the demanding electrical environment of main distribution boards and industrial machinery. With a low measurement error of ≤1% and minimal temperature coefficient of 0.05%/°C, the TBT8 delivers consistent, high-fidelity performance across its entire operating temperature range of -20°C to +55°C.

In summary, the TBT8-A and TBT8-B Three-Phase Voltage Monitoring Relays are indispensable components for any modern industrial facility. They provide a sophisticated, reliable, and user-configurable shield for motors, pumps, compressors, and other critical three-phase equipment against the damaging effects of an unstable power supply, ensuring operational continuity and protecting significant capital investment.

Applications:

-Control for connection of moving equipment(site equipment,agricultural equipent,refrigerated trucks)

-Control for protection of persons and equipment against the consequences of reverse running.

-Normai/emergency power supply switching.

-Protection against the risk of a driving load(phase failure).

Function Features

-Controls its own supply voltage(True RMS measurement).

-Set 8-level rated operating voltage through knob.

-Measuring frequency range:45Hz-65Hz.

-Voltage measurement accuracy<1%.

-Relay status is indicated by LED.

-Module,din rail mounting.

Model and connotation

Competitive Advantage:

Advantages of Wenzhou DAQUAN Electric Co., Ltd

1. Innovation Leadership

With 258 patents and 27 years of industry experience, we lead in R&D of industrial control devices like relays and timers, ensuring cutting-edge product performance.

2. Global Certifications

Our products hold CE, ROHS, IEC, TUV certifications plus ISO9001, meeting strict international standards for seamless global market access.

3. Scale Supply Stability

Backed by a 7,800㎡ factory, 499-strong team, and 70M RMB annual output, we guarantee efficient production and timely delivery for bulk orders.