4 Pole DC Circuit Breaker
  • IEC 60947-2, EN60947-2, GB 14048.2
  • 1 P=250 V DC, 2P=500 V DC 3P=750 V DC, 4P=1000 V DC
  • Different curve
  • 1A to 63A


IEC 60947-2, EN60947-2, GB 14048.2
The JB is a DC circuit breaker dedicated to multi string photovoltaic installations.
This circuit breaker is designed to protect the cables located between each string of photovoltaic modules and the photovoltaic inverter against overloads and short circuits (see application diagram).
Combined with a switch, the JB will be installed in a string PV protection enclosure at the end of each string of photovoltaic modules.
It can be locked (by a padlocking device) in OFF position as a safety measure for removal of the PV inverter.
Since a fault current can flow in the reverse direction to the operating current, the JB can detect and protect against any bidirectional current.
To ensure the safety of the installation, it is necessary, depending on the various types of application, to combine the JB with:

  • a residual current device at the AC end
  • a fault passage detector (insulation monitoring device) at the DC end
  • an earth protection circuit breaker at the DC end
    In all cases, fast action on site will be required to clear the fault (protection not ensured in the event of a double fault).

JB is not polarity sensitive: (十) and (-) wires can be inversed without any risk.
The JB is: delivered with three inter-pole barriers to providing increased isolation distance between two adjacent connectors.

1-1P DC Circuit Breaker for solar

DC circuit breaker E-catalogue, please download it below:

Langir E-Catalogue

Langir 4P DC Circuit Breaker Introduction

Langir is your highly reliable supplier of 4P DC circuit breakers from China.

You can expect 4P DC circuit breakers that are world class quality, super reliable, and built to last.

The 4P DC circuit breaker is a safety switch with a high voltage rating capacity that trips when there’s a fault in the electric current.

It is generally used in applications that have a high current rating.

It has four poles where protection is applied to the current flow through all the three poles while one is neutral.

When it trips or is opened manually, each of the four poles is disconnected.

A similar principle applies to 3P DC circuit breakers.

While the 1P and 2P DC circuit breakers normally work the same but they are typically used in low voltage applications compared to 4P DC circuit breakers.

4P DC circuit breaker

4P DC circuit breaker

The 4P DC Circuit Breaker Working Principle

The hot wires are connected to the terminals on one side of the 4P DC circuit breaker, usually on the three poles, while the 4th is for neutral.

When the 4P DC circuit breaker is switched on, the electric current flows from the hot wires and passes through the electromagnet parts (bimetallic strips on conventional types).

When the electric current spikes and reaches alarming levels, the electromagnetic reacts and moves the nearby armature that rotates the trip bar causing the 4P DC circuit breaker to trip.

This action will open the circuit, the electric current is cut, and the electromagnet coils are de-energized.

While for bimetallic strips high levels of current will cause it to bend towards the trip bar and rotate it, to open the circuit.

Different DC circuit breakers

Different DC circuit breakers

Application of the 4P DC Circuit Breaker

A 4P DC circuit breaker can be used when there are two alternative sources in a system, in power feeding systems with multiple incomers, or when you have a stand by generator or transformer feeding to a bus.

The 4P DC circuit breaker is also used for 3 phase 4 wire distribution systems.

This is where power is distributed to different substations in different locations and supplies electricity to hotels, hospitals, offices, and other similar places needing bigger voltage supply.

In any applications similar to these, it is mandatory to use the 4P DC circuit breaker.

4P DC Circuit Breaker applications

4P DC Circuit Breaker applications

Ordering the Langir 4P DC Circuit Breaker

There are several places where you can buy 4P DC circuit breakers.

Such as hardware stores, electrical stores, home depot, ecommerce websites, etc.

However, not all the 4P DC circuit breakers you’ll find are high quality.

You need to find the right brand certified supplier of high quality products such as those brands with SAA, IEC/EN 60947-2, TUV Rheinland, and similar quality seal.

Just like the certifications and quality seals that Langir has acquired for their products such as their 4P DC circuit breakers.

So when you order from Langir, you are guaranteed to receive high quality electrical products.

Langir’s 4P DC circuit breakers are easy to install, with fast delivery, and satisfaction guarantee.

Simply inquire about your circuit breaker needs and a friendly sales professional will assist you immediately.

After your orders have been confirmed, they will be delivered right away.

Send us your inquiry now.

International quality and safety seals

International quality and safety seals

Get an Instant Quote
Scroll to Top