ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Tight Terminal Screws

Damn Right, Belgian!.
I fail to see, how a screw can "un-tighten",
itself, provided that copper wires are used
and the screw is properly torqued when it is
tightened.
This whole loose terminal screw thing makes me think, that one type of Electrical worker, may be to blame for it, who could this be?, The One Screw-driver Sparkie,
their tool-kit consists of a pair of screwdrivers(1 flat blade,1 Philips), a pair of Pliers and a test lamp.
What are your thoughts on this idea?-

I don't think the screws untighten as such, but I do think connections can become loose where there is temperature cycling, due, I believe to "creep" of the relatively soft conductor metal under pressure. A particular example of this is where stranded flex of appliances used to be supplied with the ends solder tinned for ease of fitting the plug. This often used to lead to bad connections after a time.
Further thought -- Once the tightness in a connection is lost the resistance will rise leading to greater resistive heating, so perhaps there is some sort of exponential effect here until heat damage or failure due to open circuit occurs (??).

Geoff,
Welcome to ECN!.
Our Regs over here in NZ, actually prohibit the fitting of soldered wires, of any size, to screw type connections, mainly because of the heat produced by such a bad connection and the subsequent falling out of the wire, when the solder melts.