Machine Building Systems is introducing new fasteners from Item for use on aluminium profile structures structures where ESD (electrostatic discharge) is a potential problem due to the insulating layer of anodising. The Standard-Fastening Set 8 ESD (a two-part fastener consisting of a special button-head screw and load-spreading plate) and Contact Pin 8 ESD are used to connect Line 8 profiles. For easier identification, the 8 ESD fastening elements are given a yellow passivated layer (which complies with the RoHS Directive 2002/95/EC).
The Standard-Fastening Set 8 ESD is used in the same way as a conventional standard fastening set. However, the special design of the fastening screw partially destroys the insulating anodised layer on the profile groove to ensure there is a secure, long-term electrical contact between the connected profiles.
In addition, the Contact Pin 8 ESD is for use with standard Universal and Automatic fastenings. Lightly pressed into the central bore of the profile, the Contact Pin makes an electrical connection between the profiles when the fastening screws are tightened.
The contact pin works by breaking through the insulating anodised layer in the core bore and profile groove of the connected profiles.
Both ESD fittings work in such a way that if the profiles are subsequently disassembled, the marks are hardly noticeable; the important re-usability feature of the profiles and parts is therefore not compromised. Other products in Item's electrical-discharge related range include Potential Equalisers that can be retrofitted to provide ESD connections, and Earthing Terminals for use where a safety circuit is needed.