Queston On 240 Plugs and Receptacles
#1
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Queston On 240 Plugs and Receptacles
Mod note: Post separated from http://www.doityourself.com/forum/el...off-stove.html. First part copied back to that post..
Last edited by ray2047; 06-17-13 at 03:31 PM.
#2
Why would you want to use the cumbersome 14-30's on 20 amp circuits? I guess because they are there, huh? I'm using 3 pronged receptacles on all my power tools in the shop, but that's the way the motors are wired..
#3
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Sorry, mixed up from editing there.
Upgraded dryer outlets to newer 14-30 four wire plugs and outlets. (House and rentals).
The extra cords and outlets are old fashioned drier plugs, NEMA 10-30 three wire, three prong.
For 240v equipment, modern plug is 6-30, with two hots and ground. Old dryer plug is 10-30 with two hots and neutral.
Does code allow 10-30s to be reuse and rewired as 240v grounded connectors;
or does code require that millions of old cords and outlets get chucked into the landfill?
Upgraded dryer outlets to newer 14-30 four wire plugs and outlets. (House and rentals).
The extra cords and outlets are old fashioned drier plugs, NEMA 10-30 three wire, three prong.
For 240v equipment, modern plug is 6-30, with two hots and ground. Old dryer plug is 10-30 with two hots and neutral.
Does code allow 10-30s to be reuse and rewired as 240v grounded connectors;
or does code require that millions of old cords and outlets get chucked into the landfill?
Last edited by Hal_S; 06-18-13 at 05:42 AM.
#4
Grandfathered only as long as in use for original purpose. The original purpose was never for shop tools. The receptacle does not have a ground. Code says you must follow the manufacturer's recommendation. If the manufacturer says a grounded plug (or connection) then you must use a grounded plug (or connection). The plug isn't grounded and the receptacle isn't grounded. The use of this plug and receptacle was when allowed a very specific exception to the code. Shop tools were never part of that exception.
#5
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Grandfathered only as long as in use for original purpose.
"Original purpose" was a general purpose outlet, providing 240v with grounding through neutral, correct?
#7
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It was never designated for use as a 240 volt receptacle. It was designated as a 120/240 receptacle.
I'm asking about two things that are rather different,
(1) the code citation on original purpose
and
(2) the original purpose it was DESIGNED for.
The unsolved 120v/204v question from a prior discussion
Last edited by Hal_S; 06-18-13 at 06:27 AM.
#10
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Thread Starter
Originally Posted by Nashkat1
What is unsolved there ?
I figure that the earliest electric stoves would be pure 240v; the later additions of things like clock, timer and light bulb were overlooked.
But, as noted below, with a dryer there is always a fair sized motor, directly connected to the chassis...
#11
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Or I could be wrong. Old ovens with mixed 120/240, with chassis to live neutral.
Yikes.
The old ranges with seven or so pushbuttons per burner did some clever switching where the elements ran on 120 for low heat settings and 240 for high. IIRC, it was something like the small burner on 120 was low, the large burner on 120 was medium low, both on 120 was medium, and then the pattern repeats but on 240, ending with both on 240 as high.
Yikes.
The old ranges with seven or so pushbuttons per burner did some clever switching where the elements ran on 120 for low heat settings and 240 for high. IIRC, it was something like the small burner on 120 was low, the large burner on 120 was medium low, both on 120 was medium, and then the pattern repeats but on 240, ending with both on 240 as high.
#12
The 3-wire connection was permitted in WWII as an effort to save copper. Why they didn't stop permitting it after that, I don't know. Nowadays it just makes a PITA.