----- Original Message -----
From: "Jim Brown" <jim@audiosystemsgroup.com>
To: <amps@contesting.com>
Sent: Sunday, April 03, 2011 1:39 PM
Subject: Re: [Amps] what is a 4 wire 240VAC service?
> On 4/3/2011 9:48 AM, Carl wrote:
>> Altho the 4 wire has been SOP in industrial sites for ages it is a result
>> of
>> nanny state busybodies
>
> NO! Those "busybodies" to which you refer were smart electrical
> engineers who understood God's laws of physics, understood them in the
> context of "the big picture" of how buildings are wired and power is
> used, and realized the negative implications of allowing the green wire
> to carry load current, both in terms of electrical safety and electrical
> NOISE. Their work was written into the National Electrical Code, a
> model code that has subsequently been adopted by most local governments
> in North America..
Of course you edited my post out of context to conform with your rant.
>
>> Before your dryer ran the 120V motor and SS LV transformers between the
>> hot
>> side and a neutral/ground and it worked fine for 60 or so years with a 3
>> wire feed.
>
> "Worked fine" means to you that the appliances worked and nothing burned
> down. To me, it means that any noise generated in the power system by
> the appliance gets radiated by the wiring to the appliance, because the
> return path for current is not the neutral that runs in parallel with
> the hot conductor, but rather the green wire AND ALL OTHER GROUNDS
> running in parallel with the green wire, like the plumbing system. This
> causes electrical noise to radiate from that wiring like any other
> antenna, and for a magnetic field to be created that couples into low
> voltage wiring to put hum into connections between our computers and our
> radios. I don't consider that "working fine."
>
> 73, Jim Brown K9YC
To me "working fine" means the millions of appliances of which maybe .01% or
less belong to hams of which most could care less how its wired.
Im probably far above average when it comes to eliminating noise sources in
the house and the dryer and stove are completely quiet without any attention
needed, thank you. They work fine whether Im digging for signals at LF to
UHF on ham gear, vintage boatanchors or consuber tube radios going back to
the 20's.
Carl
KM1H
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