There are three important active electrical contact positions that should be noted between the power supply and the anodized aluminum workpiece.

(1) Complete "face contact" is required between conductive beam and conductive seat. If the electrical contact at this position is only point contact or line contact, then the heat will be generated during the passage of large current, resulting in the loss of current. In order to maintain a good overall surface contact, the use of a clamped electrical contact device is desirable, or the use of a water-cooled conductive seat is feasible.

On the sides of the two ends of the aluminum conductive beam, if the copper plate is welded on the side by explosive welding, corrosion will occur on the contact surface with the extension of the service time, which will significantly affect the electrification effect and increase the additional voltage drop. Therefore, it is recommended that in this case, regular inspection must be carried out.

(2) The electrical contact position of conductive rod and conductive beam can not only be suspended or bolted, but also strengthened with splint. Because after repeated use, the conductive rod and conductive beam are easy to loosen, thus affecting the effect of electrical contact, so this position must be fixed very firmly.

(3) Aluminum profile and conductive rod electrical contact do not use grain aluminum wire. To ensure good electrical contact in this position, the electrical contact area is 2A/m resistant in air and 20A/ 0.4mm in liquid.

The contact pressure of aluminum contact surface is 5kg/mm, while that of qinmu or Qinqiu alloy can reach 20kg/mm. When using fixed electrical contact devices made of aluminum, care should be taken to prevent loosening of the aluminum fasteners due to corrosion.