How to connect circuit breakers in the panel?

After the overhaul of the electrical wiring in the building or when laying new electrical networks, it becomes necessary to reliably protect the conductors from overload, as well as increase their service life. This enables reliable operation of electrical appliances. For protective purposes, circuit breakers are used that turn off the supply of electricity to the consumer when the specified power is exceeded or when a short circuit occurs. These devices are installed and connected in a switchboard. In this article we will talk about how the connection of automatic machines in the shield using a comb and jumpers.

Content:

What is important to know?
Connection Methods
Comb
Jumpers

What is important to know?

Depending on the number of phases at the input, they distinguish:

single-phase network;
three-phase network.

By installation method:

by means of a tire (comb);
jumpers from a stranded wire;
jumpers from a single wire.

Based on the initial data, it is necessary to select electrical fittings and conduct installation of circuit breakers in the panel, choosing from the above, the desired connection method for your electrical network.

Installation work for single-phase and three-phase circuits differ slightly. In a single-phase network, all circuit breakers are supplied with a single phase at the input and the machines use single ones. For a three-phase network, I use triple circuit breakers in the case of connecting a three-phase load, or you can put single on each phase separately, in the case of a single-phase load.

Connection Methods

Comb

For convenient and high-quality connection of circuit breakers in the shield, you can use the bus. Depending on the number of phases, you can choose the right comb:

for a single-phase circuit - unipolar or bipolar;
for three-phase - three- or four-pole.

Installation is very simple. For the desired number of circuit breakers, a comb with a certain number of poles is selected. If the comb has more contacts, the excess is removed (you can use a hacksaw for metal). Finishing the installation, insert the bus at the same time into all the terminals of the machines and tighten the screws. The outputs are mounted according to the scheme. More about how to connect circuit breakers with a comb, we told in the corresponding article. The video below demonstrates the connection technology:

Jumpers

This type of connection is used if there are few automatic machines and there is enough space in the shield for free access to contacts. This method can be applied to both single-phase and three-phase circuits.

To carry out work in the shield, it is necessary to prepare jumpers of suitable length and section. The cross-section of single-core conductors for connecting circuit breakers should be sufficient for the rated power consumption. About, how to calculate the current cross section of a wire we told in the corresponding article.

An ideal option would be to make jumpers in a seamless way:

From one piece of the conductor, bending it with pliers, make a jumper that will connect all the circuit breakers of the circuit. The wire must be bent with the necessary distance. After such preparation, remove the insulation from the ends by about 1 cm, strip the wire by removing the oxide film with a knife or sandpaper.

Next, you need to insert the ends into the inlets of the machines and tighten the screws. Connect all planned load sources to the output, as shown in the photo below:

It is important to remember that in this case the phase and neutral wires should not be pressed tightly against each other. This is due to the fact that during operation of the power supply network they heat up, and an undesirable connection of phase and zero can occur due to insulation softened by heating.

To connect the machines in the shield with a loop, you can also use a stranded wire of the desired cross section. But in this case, it should be stripped from insulation by 1-1.5 cm. At the end of the wire, you need to put on a tip, which corresponds in diameter to the cross section of the wire, and compress it using special pliers. Serial connection of several machines is allowed.

In the absence of the proper tool and lugs, it is permissible to lay the wire exposed from the insulation with a soldering iron. Tin or solder falls between the veins of a stranded conductor, forming a fairly strong connection of thin veins. And, although this method is considered less reliable than the previous one, it is often used due to its ease of use.

In the absence of a soldering iron, installation can also be carried out using conductors that have the insulation removed at the ends, clamping them directly into the machine. This type of installation is the least reliable and at high loads it threatens to heat the conductors in the place of association and, accordingly, an increased fire hazard. This type of connection has a not very aesthetic appearance and low reliability.

Do-it-yourself connection of automatic machines in the shield using a multicore insulated conductor must be carried out in accordance with the previously drawn up scheme. In this case, circuit breakers may not necessarily be used by one manufacturer. Their sizes may vary, because installation with a flexible wire allows you to do this.

The correct connection of the circuit breakers in the panel must be very carefully checked. This is especially true for a circuit in which 3 phases are provided. A small error can lead to a short circuit, and a loose contact can lead to overheating of the conductor and carbonization of its insulation. Under such conditions, it is possible to short circuit adjacent conductors to each other. This can cause great damage to the electrical equipment in use.

Finally, we recommend watching a video in which it is shown how to properly make a jumper to connect the circuit breakers to each other and how, in fact, to combine the devices in an electrical panel:

So we examined step by step instructions on how to connect the machines in the shield with a comb and jumpers. We hope the information provided was useful and interesting for you!

Recommended reading: