> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
> Behalf Of Bill, W6WRT
> Sent: Tuesday, November 03, 2009 10:04 PM
> To: amps@contesting.com
> Subject: Re: [Amps] TL922 Power Plugs
>
> ORIGINAL MESSAGE:
>
> On Tue, 3 Nov 2009 21:49:13 -0500, "Carl" <km1h@jeremy.mv.com> wrote:
>
> >
> >The danger is some big hungry rat or an evil person will remove your
> neutral
> >wire which will return you to the dark days of a 2 wire non polarized
> >outlets and plugs. Just think, you may only have a one wire system then
> and
> >will have to carefully reach around until your hand finds the missing
> path.
> >How some of us survived to talk about them confounds the rules makers.
>
> REPLY:
>
> That wasn't my question. Please forgive me if I wasn't clear enough.
>
> My question was this: I understand why it is necessary to bond ground and
> neutral together at the service box, but I don't understand why it is
> forbidden
> to bond them together at the appliance.
>
> There must be a scenario which causes danger but I just can't imagine what
> it
> is.
>
> 73, Bill W6WRT
If they are both bonded at the appliance both will carry neutral currents.
That can raise the appliance case above ground due to voltage drop in the
cable. Should neutral and ground become open somewhere in their path that
would put full line voltage on the appliance case.
With neutral never connected to the appliance case any or all conductors can
become open and no voltage will appear on the case unless there is a short
between a hot line and case and the ground wire becomes open.
73
Gary K4FMX
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