Copper and aluminum excessive wire clamps

Copper and aluminum cannot be welded directly, not because they can't be welded, but after welding is energized, there will be an electrochemical reaction, which will be dangerous!!

There are special copper-aluminum transitions, and the principle is to form a copper-aluminum alloy at the weld.

The Code for the Construction and Acceptance of the Busbar Device of the Electrical Installation Project clearly stipulates that when the bus bar is lapped with the busbar, the bus bar and the branch wire, and the bus and the electrical terminal, the treatment of the lap surface shall meet the following requirements:

1) Copper and copper: in the outdoors, high temperature and humidity or indoor with corrosive gas to the busbar, tinning must be made; It can be connected directly in a dry room.

2) Aluminum-to-aluminum: direct connection.

3) Copper and aluminum: In a dry room, the copper conductor should be tinned. Outdoors or indoors where the relative humidity of the air is close to 100%, a copper-aluminum transition plate should be used, and the copper end should be tinned.

Correspondingly, copper and aluminum connecting tubes can be used when copper cables are connected with aluminum cables, copper-aluminum terminals can be used when copper cables and aluminum wires are connected, and copper ends should be tinned and so on.

For this problem of yours, it is recommended to consult a professional over-wire clamp manufacturer. But as far as I know, copper-aluminum over-wire clamps are not copper-aluminum welded together. Instead, the aluminum wire clamp is partially electroplated with copper to achieve.

I don't know if you have gone to the market to take a look at the ready-made copper and aluminum wire clamps. The electroplated copper layer on the aluminum can be reached, and I don't know if this thickness is enough for your standards. If you must weld, you can use brazing, and the cost is not high.

TIG welding is the solution to this kind of problem. Simple and practical.

**As above, see for yourself.

The specific reasons are:

Copper and aluminum belong to different elements, the metal inertness of copper is greater than that of aluminum, that is, the chemical activity of copper is much lower than that of aluminum, and the electrochemical reaction will occur after the two metals are connected, resulting in the gradual oxidation of aluminum wire, reducing the mechanical strength and conductivity of aluminum wire; Copper wire and aluminum wire will heat up when passing through the current, and their resistivity is different, when passing through the same current, the heat of the aluminum wire is large, and the heat of the copper wire is small, so it is easy to cause the fault point at the joint; The hardness of copper and aluminum wire is different, if it is directly connected, its binding force is not good, if the wire is stressed greater, it is easy to break from the connection of copper wire and aluminum wire. Therefore, use copper-aluminum transition equipment clamps to avoid the above problems.

Copper-aluminum connections can produce electrochemical reactions, increase contact resistance, and burn joints, which can be avoided by using copper-aluminum transition equipment clamps.

Reason 1: Copper and aluminum belong to different elements, the metal inertness of copper is greater than that of aluminum, that is, the chemical activity of copper is much lower than that of aluminum, so that after the two metals are connected, an electrochemical reaction will occur when energized, resulting in the gradual oxidation of aluminum wire, reducing the mechanical strength and conductivity of aluminum wire Reason 2: Copper wire and aluminum wire will heat up when passing current, and their resistivity is different.

When copper and aluminum pass through the same current, the heat of the aluminum wire is large, and the heat of the copper wire is small, so it is easy to have a fault point at the joint Reason 3: The hardness of the copper wire and the aluminum wire are different, if it is directly connected, its bonding force will not be too good, and if the wire is stressed greatly, it is easy to disconnect from the connection of the copper wire and the aluminum wire.

In actual use, copper wire and aluminum wire are generally not directly connected, but copper-aluminum transition plate or copper-aluminum transition terminal produced by flash butt welding process, even if it has to be directly connected, it should be done shabu shabu treatment attached: common metal ionization energy sequence table (the metal in front can be replaced by the metal in the back from their salt solution), potassium, calcium sodium, magnesium, aluminum, zinc, iron, tin, lead (hydrogen), copper, mercury, silver, platinum.

First, check whether there is heat in the knife switch, whether its rated current is greater than 1100A, otherwise it should be replaced, and the highest temperature point can be checked with an infrared thermometer to determine the cause and location of the heat;

2. After eliminating the heat caused by the knife switch, replace the appropriate wire clamp, if the knife switch is copper, then choose the copper and aluminum excessive equipment wire clamp, if the knife switch is aluminum, then the all-aluminum equipment wire clamp can be selected;

3. The key is to check the contact surface between the knife switch and the wire clamp, if there are two holes, the equipment wire clamp is used for four holes, the contact surface is definitely not enough, and two 80 * 8 aluminum busbars can be used to transition, connected between the knife switch and the wire clamp, then the problem can be solved.

The specific reasons are:

Copper and aluminum belong to different elements, the metal inertness of copper is greater than that of aluminum, that is, the chemical activity of copper is much lower than that of aluminum, so that the electrochemical reaction will occur after the two metals are connected, resulting in the gradual oxidation of aluminum wire, reducing the mechanical strength and conductivity of aluminum wire; Copper wire and aluminum wire will heat up when passing through the current, and their resistivity is different, when passing through the same current, the heat of the aluminum wire is large, and the heat of the copper wire is small, so it is easy to cause the fault point at the joint; The hardness of copper wire and aluminum wire is different, if it is directly connected, its binding force is not good, and if the wire is stressed greatly, it is easy to disconnect from the connection of copper wire and aluminum wire.

Therefore, use copper-aluminum transition equipment clamps to avoid the above problems.

Because copper and aluminum belong to different elements, the metal inertness of copper is greater than that of aluminum, that is, the chemical activity of copper is much lower than that of aluminum, so that the electrochemical reaction will occur after the two metals are connected, resulting in the gradual oxidation of aluminum wire, reducing the mechanical strength and conductivity of aluminum wire; Copper wire and aluminum wire will heat up when passing through the current, and their resistivity is different, when passing through the same current, the heat of the aluminum wire is large, and the heat of the copper wire is small, so it is easy to cause the fault point at the joint; The hardness of copper wire and aluminum wire is different, if it is directly connected, its binding force is not good, and if the wire is stressed greatly, it is easy to disconnect from the connection of copper wire and aluminum wire. Therefore, use copper-aluminum transition equipment clamps to avoid the above problems.

It is best to use the brazing copper-aluminum transition equipment clamp first, and now a lot of friction welding copper-aluminum transition equipment clamp is broken, and there will be many times this kind of thing every year, causing great losses, it is best to choose brazing.

Reason 1: Copper and aluminum belong to different elements, the metal inertness of copper is greater than that of aluminum, that is, the chemical activity of copper is much lower than that of aluminum, so that the electrochemical reaction will occur after the two metals are connected, resulting in the gradual oxidation of the aluminum wire, reducing the mechanical strength and conductivity of the aluminum wire Reason 2: Copper wire and aluminum wire will heat up when passing current, and their resistivity is different copper and aluminum.

When passing through the same current, the heat of the aluminum wire is large, and the heat of the copper wire is small, so it is easy to have a fault point at the joint Reason 3: The hardness of the copper wire and the aluminum wire are different, if they are directly connected, the binding force will not be too good, and if the wire is stressed greatly, it is easy to disconnect from the connection of the copper wire and the aluminum wire.

In actual use, copper wire and aluminum wire are generally not directly connected, but copper-aluminum transition plate or copper-aluminum transition terminal produced by flash butt welding process, even if it has to be directly connected, it should be done shabu shabu treatment attached: common metal ionization energy sequence table (the metal in front can be replaced by the metal in the back from their salt solution), potassium, calcium sodium, magnesium, aluminum, zinc, iron, tin, lead (hydrogen), copper, mercury, silver, platinum.

The gray-white substance generated at the connection of copper wire and aluminum wire is aluminum oxide, and for a longer time, the contact resistance at the connection will increase and heat, resulting in the circuit being on and off and it is easy to cause a building fire. Therefore, it is necessary to use a special copper-aluminum transition wire clamp. Avoid unnecessary hassle!

Copper-aluminum wire connection devices (commonly known as "copper-aluminum nose").