Pro earth cable 5 m 400 A

Using electrolytic copper with a 70 mm² cross section in the PRO series gives 40% higher current conductivity than standard 50 mm² sets. At 400A the current density per square millimetre stays at a level that does not cause a sharp rise in conductor temperature, which protects the molecular structure of the copper against accelerated oxidation. The physics behind this rests on low dynamic resistance, which lets the power source correct the arc instantly in pulsed processes. With this cross section the earth cable acts as a stabilising heat sink, which means less load on the rectifier bridges inside the machine. It is a key element behind the long life of the equipment and full technical support for advanced arc control algorithms.

The insulation of the SpawLab PRO cable is made to the H01N2-D standard, which means chloroprene rubber of raised density. This material is chemically resistant to greases, engine oils and ozone, which is needed in demanding workshop conditions. The physical strength of the insulation protects the copper core against mechanical rupture when a transport trolley runs over it or when it chafes on the sharp edges of prefabricated parts. Chloroprene is also self-extinguishing, which raises fire safety at the welding station if spatter lands on the cable. The jacket stays flexible even at sub-zero temperatures, which makes outdoor assembly work far easier, where stiff rubber cables tend to crack.

In the PRO series we use only cast brass clamps, which have a far higher thermal and electrical conductivity than pressed steel clamps. The brass body holds a stable contact point with the material, which at 400A removes the risk of stray arcing that could melt the surface of the part. A solid clamping spring with a high spring rate secures a reliable mechanical connection, which is decisive for keeping the transition resistance at the clamp to material contact as low as possible. Each clamp is joined to the 70 mm² cable through a copper ferrule, which removes weak points in the current path. A joint built this way keeps the clamp handle from overheating, which directly raises welder comfort during long working cycles.

When welding with MMA, the symmetry of the electrical circuit has a critical effect on the stability of the welding arc. By using the PRO earth cable with a 70 mm² cross section, the operator can build a perfectly balanced system together with an electrode cable of the same rating. That configuration reduces arc blow, which often appears when welding with high direct current. A voltage drop of 1.26 V across the full MMA circuit means the Hot Start function works at maximum effect and makes it easier to strike even difficult cellulosic electrodes. This is a deliberate SpawLab engineering choice meant to give the user a tool with laboratory behaviour under field conditions. Mirror-Balance also lowers the risk of damage to the control electronics, which no longer has to compensate for asymmetry in the secondary circuit.