What is a double pole breaker?

A bipolar circuit breaker is an electrical protection device used to provide overload and short circuit protection in a circuit. The main difference between it and the single-pole circuit breaker is that the bipolar circuit breaker can control two electrical routes at the same time (usually the live line and the neutral line), while the single-pole circuit breaker can only control one electrical route.

Characteristics of bipolar circuit breakers

• Control two lines at the same time: bipolar circuit breakers can disconnect two lines at the same time, usually Live and Neutral lines, which can ensure that the circuit is completely disconnected and avoid safety hazards caused by unilateral disconnection.

• Improved safety: In some cases, simply disconnecting the fireline may not be enough to guarantee safety, as there may still be voltage in the circuit. By disconnecting the live and neutral lines at the same time, the current flow in the circuit can be completely eliminated, thus improving safety.

• Space saving: In some distribution boxes or cabinets, using one bipolar circuit breaker can save space because there is no need to install two separate single-pole circuit breakers to control the live and neutral lines separately.

Application scenario

Bipolar circuit breakers are suitable for situations where two lines need to be controlled at the same time, especially in applications where it is necessary to ensure that the circuit is completely disconnected, such as:

• Household appliances: In the home distribution box, the bipolar circuit breaker can be used to control the circuit in the kitchen, bathroom and other humid environments to ensure the safety of power failure.

• Industrial equipment: In industrial environments, bipolar circuit breakers can be used to control the circuits of motors, pumps and other equipment to ensure that the circuit is completely disconnected during maintenance or overhaul.

• Lighting systems: For circuits that need to control multiple luminaires at the same time, the use of bipolar circuit breakers can simplify circuit design and improve safety.

Working principle

When the current in the circuit exceeds the predetermined value, the bipolar circuit breaker will automatically trip and cut off the circuit. This process is usually achieved by a built-in electromagnetic mechanism or thermal element, which can detect overload or short circuit and trigger the action of the circuit breaker.

Type of circuit breaker

Bipolar circuit breakers can have different types, according to their protection characteristics and design, common types include:

• Electromagnetic circuit breaker: Detect the current change through the principle of electromagnetic induction, and automatically disconnect the circuit when the current exceeds the set value.

• Thermal magnetic circuit breaker: combined with thermal protection and magnetic protection functions, it can not only deal with long-term overload conditions, but also quickly respond to short circuit faults.

• Solid-state circuit breaker: The use of solid-state devices (such as transistors) to control the on-off of the circuit, faster response, suitable for applications requiring high-speed protection.

Sum up

Bipolar circuit breaker is an electrical device used to protect the circuit from overload and short circuit damage, it can disconnect two electrical routes at the same time, providing greater safety. Bipolar circuit breakers are a very practical option in applications where you need to ensure that the circuit is completely disconnected.