{Collins} Re: 30S-1 230V wiring



I've dealt with residential appliances for several years now and the same
applies here to the older Collins equipment as well as others.  The
electrical code (NEC) changed some 4 or 5 years ago.  This change did
require that new construction and remodeled homes must meet the current
standards.  This included mobile homes.  The new standards require 4 wire
systems for electric clothes dryers and electric ranges.  Replacement
appliances going into older homes etc were still "legal" when used with 3
wire systems.  The same will apply to the older radio equipment.

The new wiring convention conveys that ground is ground and neutral is
neutral.  They are not the same.  In a 230 volt single phase service, the
neutral carries the differential current between the two legs.  If current
in L1 and L2 are equal then the neutral current is zero.  However, if L1 and
L2 are of different loads then the difference is handled by the neutral.
With the neutral having some value of R, using the neutral for equipment
ground will assure that the equipment is not at zero volts potential.  In
the new NEC rules, the safety ground is in place to assure that the
equipment cabinet is at zero potential.

73
Bob, K4TAX


----- Original Message ----- 
From: "kmarshall1" <kmarshall1@xxxxxxxxxxxxxx>
To: <scottjohnson1@xxxxxxx>; "Collins Reflector Posting"
<collins@xxxxxxxxxxxxx>
Sent: Thursday, July 08, 2004 7:47 AM
Subject: {Collins} Re: 30S-1 230V wiring


> Scott:
>
> The 30S-1 was correctly designed within the standards of that day.
>
> "Older 230V installations such as dryers and ranges often violated this
> rule, as they only used three conductors with no
> dedicated safety ground."
>
> True, there may not have been a "dedicated safety ground", but there was
no
> "rule" violated.  What was designed, and done, was according to the
National
> Electrical Code in force at the time.  The NEC is re-issued every three
> years, and, trust me, there ARE changes as time goes on.  The reason the
> Code is changed is because technology changes, but also because better
ideas
> come along.  Four-wire systems were one of those things that were better
> ideas.
>
>
> Kent W5TXV
>
>
> ----- Original Message ----- 
> From: "Scott Johnson" <scottjohnson1@xxxxxxx>
> To: <culpepper@xxxxxxxxxxxxx>; <roy.morgan@xxxxxxxx>; <w7ksg@xxxxxxxx>;
> "Collins Reflector Posting" <collins@xxxxxxxxxxxxx>
> Sent: Wednesday, July 07, 2004 8:35 PM
> Subject: {Collins} Re: 30S-1 230V wiring
>
>
> > First of all, it is improper to think of L1 and L2 as "phases", they are
> not
> > polyphase.  A 230V service is single phase, it is simply fed from a
230VCT
> > transformer, and the CT is grounded, this is the neutral, and the safety
> > ground at the panel.  From that point, though, the neutral should never
be
> > thought of as a safety ground, nor should the safety ground be called
upon
> > to carry neutral current.  Older 230V installations such as dryers and
> > ranges often violated this rule, as they only used three conductors with
> no
> > dedicated safety ground.  Dryers do indeed use a neutral,for the motor,
> > light and timer are usually 115V, only the element is 230V.  Bottom line
> is,
> > and I know this is blastphemy, the 30S-1 is poorly designed from a
safety
> > viewpoint, and should have had a conrol transformer for the 115V
cicuits,
> or
> > have had a four wire service.  Since four wire services were rare in the
> > days that it was designed, the former should have been included. I
rewired
> > my 30S-1 with a four wire service and isloated the neutral from ground.
> > 73,
> > Scott
> > ----- Original Message ----- 
> > From: "William Culpepper" <culpepper@xxxxxxxxxxxxx>
> > To: <roy.morgan@xxxxxxxx>; <w7ksg@xxxxxxxx>; "Collins Reflector Posting"
> > <collins@xxxxxxxxxxxxx>
> > Sent: Wednesday, July 07, 2004 4:56 PM
> > Subject: {Collins} Re: 30S-1 230V wiring
> >
> >
> > > I wrote this prior to seeing the message from Bob, WB4TGG, and he
> covered
> > > much of the 30S-1 230 volt thing, but since I have already written
this,
> I
> > > will send it anyway.
> > >
> > > A clothes dryer is a 230 volt device.  It does not use 115 volts, and
> the
> > > three wires consist of two wires that supply 230 volts and a
non-current
> > > carrying ground wire for a safety ground.
> > >
> > > The 30S-1 uses 230 volts for the plate transformer and 115 volts for
> > > filament transformers, bias transformers, blower motors, time delay
> > relays,
> > > etc.  Therefore it must have a current carrying neutral to supply the
> 115
> > > volts.
> > >
> > > To meet the current National Electrical Code, the 30S-1 must NOT have
> the
> > > neutral conductor connected to the chassis. (I do not have a 30S-1,
but
> I
> > do
> > > have a schematic of unknown date, and the neutral is not shown as
being
> > > connected to the chassis.)   The ground wire (the green wire) is
> connected
> > > to the chassis/cabinet, and it must be a separate conductor all the
way
> > back
> > > to the ground buss in the breaker panel.  And, the 30S-1 must have a
> four
> > > prong plug to meet the current code.  (It MIGHT meet some provision of
> the
> > > code if it has a separate ground wire from the "ground" connection on
> the
> > > amplifier to a "real" ground, and this is obviously what The Collins
> Radio
> > > Company intended, but I would prefer the four prong plug with green
wire
> > > back to the panel.)  The power cord meeting the current code will have
> > four
> > > wires - two wires carrying 230 volts, usually black and red; a white
> > neutral
> > > and a green ground wire.
> > >
> > > I might not have read all of this thread, and I apologize if I am
> > repeating
> > > someone before me, but I believe the National Electrical Code was
> changed
> > > between the time the first and last 30S-1 was manufactured.  If the
> > > amplifier was manufactured prior to the code change, it is probably
> > > "grandfathered" in, but that won't help you if you get electrocuted
with
> > it,
> > > which is not very likely, but the Code was changed to require a
separate
> > > ground for a good reason.  If you don't understand it, get competent
> help.
> > >
> > > I do not consider myself competent on the Code, and I solicit a
critique
> > of
> > > the above from anyone who disagrees with anything I have said.
> > >
> > > William
> > > W4BZ
> > >
> > >
> > > Sponsored by the Collins Collectors Association
> > http://www.collinsradio.org
> > > Nets: Tues: 3.805 Mc-2000 Central / Thur: 3.875 Mc-2000 Central
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> > >
> >
> > Sponsored by the Collins Collectors Association
> http://www.collinsradio.org
> > Nets: Tues: 3.805 Mc-2000 Central / Thur: 3.875 Mc-2000 Central
> > Fri: 3.895 Mc-2000 Pacific / Sun: 14.263 Mc-2000 UTC
> > 1st Wed (of the month) AM Net 3.880 Mc-2000 local (ET, CT, MT, PT)
> > Sun AM Net: 29.050 Mc-1200 Central
> >
> >
>
>
> Sponsored by the Collins Collectors Association
http://www.collinsradio.org
> Nets: Tues: 3.805 Mc-2000 Central / Thur: 3.875 Mc-2000 Central
> Fri: 3.895 Mc-2000 Pacific / Sun: 14.263 Mc-2000 UTC
> 1st Wed (of the month) AM Net 3.880 Mc-2000 local (ET, CT, MT, PT)
> Sun AM Net: 29.050 Mc-1200 Central
>
>


Sponsored by the Collins Collectors Association http://www.collinsradio.org
Nets: Tues: 3.805 Mc-2000 Central / Thur: 3.875 Mc-2000 Central
Fri: 3.895 Mc-2000 Pacific / Sun: 14.263 Mc-2000 UTC
1st Wed (of the month) AM Net 3.880 Mc-2000 local (ET, CT, MT, PT)
Sun AM Net: 29.050 Mc-1200 Central






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