ABB TA25 DU 32 thermal overload relay

ABB TA25 DU 32 thermal overload relay

Product core positioning

ABB TA25 DU 32 is a three pole electromechanical thermal overload relay, belonging to the ABB TA series motor protection products, designed specifically for three-phase asynchronous motors. Its core function is to quickly cut off the circuit in case of motor overload, phase failure, or current imbalance faults, avoiding motor winding burnout or equipment damage. It is usually used in conjunction with ABB A-Line series contactors (such as AX09-AX40 type) to form the basic circuit for motor control and protection, and is widely applicable to industrial motor systems with voltages up to 690V AC and 800V DC.

Key technical specifications

1. Electrical core parameters

Set current range: 24-32A, can accurately adjust the protection threshold according to the rated current of the motor.

Rated voltage: The main circuit supports 690V AC and 440V DC; The auxiliary circuit is compatible with 500V AC and 440V DC to meet the needs of medium and high voltage industrial scenarios.

Rated current: Rated operating current (I ₑ) of 32A, rated current of 32A under AC-3 working mode, suitable for high-power motor loads.

Insulation and impact resistance performance: rated insulation voltage 690V, rated impact withstand voltage 6kV, ensuring electrical safety in strong electrical environments.

2. Physical and environmental parameters

Dimensions: 44mm (width) x 94mm (height) x 94mm (depth), net weight 0.49lbs, compact design suitable for dense layout of control cabinets.

Installation method: Supports 35mm DIN rail installation, can be directly inserted and matched with the contactor, or fixed separately through an independent installation kit.

Environmental adaptability: Operating temperature range -25 ℃~+70 ℃ (some data indicate -25 ℃~+55 ℃), IP20 protection level, dustproof performance suitable for the environment inside industrial control cabinets.

3. Certification and Standards

Compliant with international standards such as IEC 60947-4-1, UL, CSA, CE, etc., the phase loss sensitivity and trip characteristics meet the stringent requirements of industrial motor protection.

Core protection functions and design

1. Multi dimensional fault protection mechanism

Overload protection: Adopting the principle of bimetallic strip heating tripping, when the motor is overloaded, the bimetallic strip is heated and bent to trigger tripping, with a tripping level of 10A (i.e. tripping within 10 seconds under 10 times the rated current), balancing fast response and misoperation protection.

Phase failure and unbalance protection: The three-phase circuit is equipped with bimetallic monitoring, which will immediately activate when any phase is disconnected or the current is unbalanced, to prevent the motor from burning out the winding during single-phase operation.

Tripping independence: equipped with a free tripping mechanism, even if the reset button is operated incorrectly and the fault is not resolved, it still maintains the tripping state to prevent secondary damage.

2. Operation and diagnostic characteristics

Reset mode: Supports manual/automatic reset switching. Automatic reset is suitable for unmanned scenarios, and manual reset is convenient for confirming startup after troubleshooting.

Status indication: The front end is equipped with a trip indicator light, which provides intuitive feedback on the protection action status; Built in 1 set of normally open (NO) and 1 set of normally closed (NC) auxiliary contacts, which can be linked to an alarm system or PLC for remote monitoring.

Testing function: Integrated manual testing button, can simulate overload state to verify the effectiveness of protection circuit, simplify operation and maintenance debugging process.

Adaptation system and application scenarios

1. Supporting facilities and expansion

Core adaptive contactor: specially designed for ABB AX09-AX40 contactor, plug-in connection reduces wiring and improves circuit reliability.

Optional accessories: Provide terminal covers, busbar kits, remote trip/reset modules, and other accessories that can expand protection levels and remote control capabilities.

2. Typical application areas

Covering industries such as manufacturing, automotive, HVAC, metallurgy, and chemical, with specific scenarios including:

Overload and phase failure protection for production line drive motors, fan and water pump motors;

Motor safety circuits for continuous operation equipment such as compressors and conveyors;

Supporting protective devices for small and medium-sized motors in medium voltage distribution systems.