Earth Wire of Heating Cable

There are four main types of earth wire for the grounding system of heating cable, which are:

Type 1 - Solid earth wire plus alu-foil screen

Type 2 - Stranded earth wire plus alu-foil screen

Type 3 - Multiple, parallel and thin earth wires plus alu-foil screen

Type 4 - Earth braid and shield

Type 1 (Solid earth wire) and Type 2 (stranded earth wire) plus an extra layer of alu-foil screen are mainly used for the grounding system of standard (3.6mm thickness) twin conductor heating cables with PVC jacket. The heating cables with such grounding systems are round.

Type 3 (Multiple thin earth wires) plus an extra layer of alu-foil screen is mainly used for the grounding system of standard (3.6mm thickness) twin conductor heating cable with PVC jacket to reduce the cable thickness, especially applied in the in-slab heating cable design. The heating cables with this grounding system are oval.

Type 4 (Earth braid and shield without alu-foil screen) is especially used for PVC single conductor heating cables and nylon or teflon (ultra-thin - 2.0mm) twin conductor heating cables to minimise the cable thickness. The heating cables with this grounding system are oval.

Remarks:

Alu-foil screen with inside electrical conductive makes sure earth wire 100% grounding, meanwhile works as a shield to reduce the EMF by fully wrapping around the heating conductor.

Earth braid forms a shield like alu-foil screen to make sure 100% grounding and also reduce the EMF radiation emitted by heating conductor.