How to do it - Connect aluminum wires correctly
When stripping an aluminum wire, a thin, non-conductive oxide layer forms on the surface.
This must be broken through in order to ensure safe and current-carrying contact in the modular terminal block.
This means it is necessary to perform the following steps before connecting:
- Scrape the oxide layer on the stripped end of the aluminum wire with a blade.
It is not recommended to remove the oxide layer with a wire brush, because particles that increase the contact resistance of the connection remain on the wire.
- Immediately after removing the oxide layer, dip the bare aluminum wire in non-acid and non-alkali (neutral) Vaseline.
- The installation site should be as free from humidity and aggressive atmospheres as possible.
- The wires pretreated in this way are connected to the screw terminal block with the maximum torque.
- The pretreatment must be repeated when connecting the conductors anew.
Screw terminal blocks up to 240 mm² are ideal for the connection of aluminum wires
Detailed information about connecting aluminum wires
In the PDF document, you will find further information about this topic in English and German, as well as a list of all authorized screw terminal block and aluminum wire combinations (wire type and cross section).
When connecting aluminum wires, which have not been expressly authorized in terms of wire type or cross section, to Phoenix Contact modular terminal blocks, we recommend using what are called AlCu bimetallic pin sleeves, which are offered by Elpress and Klauke, for example.
- Connecting aluminum wires to Phoenix Contact screw terminal blocks (PDF 0,08 MB)
- Further information about screw connection terminal blocks