China Supplier of Motor Thermal Circuit Breakers

A thermal circuit breaker is a temperature-sensitive circuit protection device. It triggers circuit breaking by the deformation of a bimetallic strip, primarily used to protect equipment from damage caused by overload or abnormal temperatures.

Our thermal circuit breakers offer both thermal over-current trip-free and magnetic/hydraulic trip-free operation. Thermal Circuit breakers can be reset manually or automatically to resume normal operation. Thermal protection circuit breakers are temperature sensitive, single and double pole, fixed time delay, push-to-reset or switch function, and a compact design. Magnetic and hydraulic operation circuit breaker relays are not temperature sensitive. We offer single-pole or multi-pole circuit breakers, including 2-pole, 3-pole, and 4-pole versions. Our portfolio includes circuit breakers with various time delays and switch functions. These are side-by-side stackable. Our circuit breakers are designed for use in various applications, including industrial controls, aviation and marine systems, 暖通空調系統, pool/spa controls, 燈光, test and measurement equipment, commercial appliances, 醫療器材, and surge protection.

Micro Thermal Circuit Breaker 28VDC, 250交流電, 8A, for threadneck panel mounting

Circuit Breaker Thermal Overload Protector, Manual Reset Overload Switch Black UL CE

Thermal Circuit Breakers with Rocker and Push

The following are its key features:
我. Working Principle and Characteristics
‌Bimetallic Strip Structure‌
Composed of two metal strips with different thermal expansion coefficients, connected in series in the circuit. When the current overloads, the metal strips bend due to heat, mechanically triggering the contacts to separate and disconnect the circuit.

It features a manual reset function and is reusable, unlike disposable fuses.

‌Environmental Adaptability‌
The protection threshold automatically adjusts as the ambient temperature rises, resulting in faster tripping and lower trigger current at high temperatures. It has strong resistance to mechanical shock and vibration and has been tested to operate stably within the 5-15Hz frequency range.

斷路器 – Chinese Supplier of Thermal and Magnetic-Hydraulic

Motor Thermal Circuit Breaker, Series Trip, 250 交流電, 50 直流電壓, 1 極, 5 – 30 seconds Trip Time at 200%

熱斷路器, Series Trip, 250 交流電, 32 直流電壓, 10A, 1極

二. Technical Standards and Classifications
National Standard: Complies with GB 4943.1-2011/IEC 60950-1:2005, defined as a non-manually adjustable temperature-sensitive protective device.
Type Examples:
K-type thermal circuit breakers: Commonly used in industrial scenarios, such as the Schneider GV2 series motor protector, which supports a current range of 0.1A-32A.
Molded Case Circuit Breakers: Such as the Schneider CVS400F, suitable for high-current distribution protection from 320A to 630A.

三、. Application Scenarios
家用電器: Overload protection for air conditioners and electric water heaters.
Industrial Equipment: 馬達保護 (such as the Schneider GV2ME series) and short-circuit protection for power distribution systems.
醫療器材: Temperature anomaly protection in power management systems.

四號. Selection Recommendations
Current Matching: Select a circuit breaker based on the rated load current. 例如, for home use, a 1P+N circuit breaker (such as the Chint NB3 series) is recommended. For industrial motors, the thermal-magnetic GV2ME is recommended.
環境因素: For high-temperature environments, pay attention to the circuit breaker’s temperature compensation performance.