Electrical Engineering - Octagonal Junction Boxes

Author

Octagonal Junction Boxes

ted@schaarcommunications.com

2007-11-09, 5:25 pm

I know this is a thin slice, but I am doing a research project that
involves octagonal electrical junction boxes. Does anyone know when
these boxes were first used in America? According to a Wikipedia
article, "knob and tube wiring (sometimes abbreviated K&T) was the
earliest standardized method of electrical wiring in buildings, in
common use from about 1880 to the 1930s." It appears to me that this
approach didn't use junction boxes much so they probably didn't come
on the scene until the thirties or so. Thanks in advance for any
help. Ted

Bill Shymanski

2007-11-10, 3:25 am

ted@schaarcommunications.com wrote:
> I know this is a thin slice, but I am doing a research project that
> involves octagonal electrical junction boxes. Does anyone know when
> these boxes were first used in America? According to a Wikipedia
> article, "knob and tube wiring (sometimes abbreviated K&T) was the
> earliest standardized method of electrical wiring in buildings, in
> common use from about 1880 to the 1930s." It appears to me that this
> approach didn't use junction boxes much so they probably didn't come
> on the scene until the thirties or so. Thanks in advance for any
> help. Ted
>

The Crouse-Hinds company had some stuff on their 100'th anniversary last
year - they started off making fittings with removable covers to allow
electrical wiring to be pulled into pipes. Regular plumbing elbows were
solid and didn't give access to allow wires to be pulled. So, I suspect
use of octagon boxes couldn't have started much before 1906 or so.

The Wikipedia article is talking about the North American version of
wiring. According to a book I read, a few inventors in the UK patented
various forms of metal-enclosed wiring for buildings back in the 1890's,
using either a lead sheath (just like a buried cable) or a brass rolled
sheath that was soldered closed. However, the description I read
doesn't show any junction boxes, octagon or other.

Perhaps Ideal or other manufacturer's sites would have some history.
Old-time ads in electrical trade publications would be a good place to
look as well. Since two-conductor cables (Loomex, Romex, etc.) started
in the late 1920's, I suspect octagon boxes would not have gotten
popular much before then.

I've seen K&T wiring into octagon boxes for lamps, but I haven't seen
any really old buildings (1900's) with original wiring.

Good luck with the research...somewhere there's a musty old pile of
trade magazines with the new product announcement in them that you're
looking for.

Bill

( The book I found is Robert M. Black, The History of Electric Wires
and Cable, Peter Pergrinus Ltd.London, 1983 ISBN 0 86341 001 4, and
talks about early building wiring on pages 155-158 )

Mike Lamond

2007-11-15, 3:25 am

"Bill Shymanski" <wtshyman@mts.net> wrote in message
news:ykaZi.14$kl7.9@newsfe21.lga...
> ted@schaarcommunications.com wrote:
>
> The Crouse-Hinds company had some stuff on their 100'th anniversary last
> year - they started off making fittings with removable covers to allow
> electrical wiring to be pulled into pipes. Regular plumbing elbows were
> solid and didn't give access to allow wires to be pulled. So, I suspect
> use of octagon boxes couldn't have started much before 1906 or so.
>
> The Wikipedia article is talking about the North American version of
> wiring. According to a book I read, a few inventors in the UK patented
> various forms of metal-enclosed wiring for buildings back in the 1890's,
> using either a lead sheath (just like a buried cable) or a brass rolled
> sheath that was soldered closed. However, the description I read doesn't
> show any junction boxes, octagon or other.
>
> Perhaps Ideal or other manufacturer's sites would have some history.
> Old-time ads in electrical trade publications would be a good place to
> look as well. Since two-conductor cables (Loomex, Romex, etc.) started in
> the late 1920's, I suspect octagon boxes would not have gotten popular
> much before then.
>
> I've seen K&T wiring into octagon boxes for lamps, but I haven't seen any
> really old buildings (1900's) with original wiring.
>
> Good luck with the research...somewhere there's a musty old pile of trade
> magazines with the new product announcement in them that you're looking
> for.
>
> Bill
>
> ( The book I found is Robert M. Black, The History of Electric Wires and
> Cable, Peter Pergrinus Ltd.London, 1983 ISBN 0 86341 001 4, and talks
> about early building wiring on pages 155-158 )

Don't forget period textbooks on electricity and electrical systems. I have
one from International Correspondence Schools titled "Electric Lighting and
Railways," copyright 1901 by International Textbook Company. It must be
part of a series, since it has several sections, covering Dynamo-Electric
Machinery (Section 11), Alternating Currents (Sections 12, 13) and Interior
Wiring (Sections 26 - 28).

It mentions several recent advances including the National Electric Code;
iron conduit; stamped steel outlet and junction boxes with knockout discs
and plaster rings; and flexible armored or Greenfield conduit "made of
steel ribbon wound spirally." The illustrations show a square steel box
along with the conduit check nut and insulation cap, along with round
and rectangular cast iron boxes but no octagonal boxes. The brass
rolled sheath Bill refers to is mentioned as part of one of the first
conduit
systems but already not allowed by the Underwriters. It consists of
paper wound to form a tube and coated with tar inside and out. The
paper tubes were brittle, and covering them with a thin shell of sheet
brass came along as an improvement. This was once "considered the
best possible kind of construction."

When I was an EE student in the early 1980's, one of the computer
graphics labs was in the building where Clarkson was founded in 1896.
One day I noticed that the ceiling was open around the light in the front
entrance and realized that we still had knob-and-tube wiring in the
same building as the VAX 11/780.

Mike

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