----- Original Message -----
From: "Tony Duell" <ard_at_p850ug1.demon.co.uk>
To: <cctalk_at_classiccmp.org>
Sent: Thursday, December 12, 2002 7:41 PM
Subject: Re: dryers was Re: Acquired a PDP11/44, but missing M7095
> >
> > The old style dryers that I've looked at used 120V timers connected
between
> > one hot leg and the chassis ground. It might not live up to the latest
and
> > greatest code, but I was never shocked by one. YMMV.
>
> I think the main hazard is if the earth/neutral wire becomes
> open-circuit, then the frame of the drier becomes live via the timer
> motor windings, which are not that high impedance. I don't like large,
> live, metal objects around, particularly if there's also water about (and
> this would be likely near a clothes drier).
>
> That's why there are separate neutral and earth wires, even if they are
> then connected together at one point in the installation. If the neutral
> wire breaks, the device fails to work, but it doesn't become live. If the
> earth wire breaks, the device carries on working, but will become live
> _if another fault develops_. Combine the 2 into one wire, and if that
> breaks, the device stops work _and_ becomes live.
I understand the problems it can cause. My problems with these sort of
regulatory agencies are their complete arrogance and flighty nature. Every
three years, they come out with a new Code. Which is fine, but they
absolutely *insist* that the current Code is the most safe, and that all
others are unsafe. The problem I see with that statement is that they said
the exact same thing three years earlier, and look what became of that... I
just can't see a committee publishing the best of anything, let alone
something as complex as this.
Note: I do think the Code gets better and better. I follow it with all my
work. Please read, understand, and follow the Code when working with
electricity!
>
> -tony
Bob
Received on Fri Dec 13 2002 - 05:32:00 GMT