MicroVAX 3800 Power Cable

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Fri Feb 7 17:55:00 2003

> On Feb 6, 22:33, Tony Duell wrote:
>
> > I don't see how you can do a proper test without a visual inspection
> of
> > the connections... And I've yet to see a moulded connector that
> provides
> > a proper strain-relief for the cable.
>
> A good PAT tester will check at a sensible current (though admittedly a
> lot only check earth continuity at a proper current). As for strain

I've never met a PAT tester that tests the current-carrying conductors at
a significant current, mainly because there's no easy way to do this
without dismantling the unit under test (if the cable is fixed) -- the
maximum current you could pass would be the normal operating current of
the unit (by simply applying mains to it), which is not enough. Even then
you couldn't measure the voltage drop across one of the conductors.

You may have guessed that I don't trust PAT testers, and I have no faith
at all in the safety standards as usually applied. Proper safety tests on
the other hand...

> releif, well you're not supposed to swing the equipment by the power
> cable, Tony!

True, but equally I don't expect the outer covering of the cable to pull
out of the moulded connector in normal use exposing the single-insulated
wires inside. Which has happened to many moulded cables round here.

I assume you'd fail a rewirable plug with the cord grip missing/not used
on an electrical safety test. I certainly would. But most moulded cables
are not a lot better than that.

> > The cable mounted section looks like a normal 'cold condition'
> _socket_,
> > but there are 3 round pins sticking out of the face of it (where the
> > socket holes would be). The chassis part looks like the normal plug
> > (recessed into the panel, etc) with 3 holes in it in place of the
> normal
> > plug pins.
>
> I've a feeling I've seen this used somewhere -- but not recently, and I
> can't think where :-(

I've thought of another place I've seen them used. Leitz Focomat 1
enlarger, at the top of the column. Connector for the lampholder assembly.

-tony
Received on Fri Feb 07 2003 - 17:55:00 GMT