Well, cabinet trim went fine, range fits and is centered (probably
should have greased the sides a bit goilg in) currently wiring the new
range.
romex into the 50 Amp wall plug is three wire, which was code
acceptable then and now for reinstallation. However, old range was
wired with a four wire plug. Nuetral and ground are tied together in
the male end of the plug (which I am reusing).
four wire hookup calls for hooking up black, white (nuetral) and red
on the terminal block and *removing* a bonding strap from the ground
screw to the nuetral terminal on the ground, then attaching the ground
wire to the now chassis only ground screw.
Three wire hook up calls for black, white (nuetral) and red, no ground
wire and leaving the bonding strap in place.
I'm going to assume that the former is better despite the fact there
is no separate nuetral and ground returning to the box, they are at
least separate leaving the appliance.
Or maybe it doesn't matter?
Frank
This is still present in the 2005 NEC but notes show it has been
edited.
Mike M
250.140 Frames of Ranges and Clothes Dryers. Frames
of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction
boxes that are part of the circuit for these appliances
shall be grounded in the manner specified by 250.134 or
250.138.
Exception: For existing branch circuit installations only
where an equipment grounding conductor is not present in
the outlet or junction box, the frames of electric ranges,
wall-mounted ovens, counter-mounted cooking units, clothes
dryers, and outlet or junction boxes that are part of the
circuit for these appliances shall be permitted to be
grounded to the grounded circuit conductor if all the
following conditions are met.
(1) The supply circuit is 120/240-volt, single-phase, 3-wire;
or 208Y/120-volt derived from a 3-phase, 4-wire, wyeconnected
system.
(2) The grounded conductor is not smaller than 10 AWG
copper or 8 AWG aluminum.
(3) The grounded conductor is insulated, or the grounded
conductor is uninsulated and part of a Type SE serviceentrance
cable and the branch circuit originates at the
service equipment.
(4) Grounding contacts of receptacles furnished as part of
the equipment are bonded to the equipment.
On Tue, 13 Nov 2007 11:41:36 -0600, Frank Boettcher
<[email protected]> wrote:
>
>Well, cabinet trim went fine, range fits and is centered (probably
>should have greased the sides a bit goilg in) currently wiring the new
>range.
>
>romex into the 50 Amp wall plug is three wire, which was code
>acceptable then and now for reinstallation. However, old range was
>wired with a four wire plug. Nuetral and ground are tied together in
>the male end of the plug (which I am reusing).
>
>four wire hookup calls for hooking up black, white (nuetral) and red
>on the terminal block and *removing* a bonding strap from the ground
>screw to the nuetral terminal on the ground, then attaching the ground
>wire to the now chassis only ground screw.
>
>Three wire hook up calls for black, white (nuetral) and red, no ground
>wire and leaving the bonding strap in place.
>
>I'm going to assume that the former is better despite the fact there
>is no separate nuetral and ground returning to the box, they are at
>least separate leaving the appliance.
>
>Or maybe it doesn't matter?
>
>Frank
Mike Marlow wrote:
> The only time it's "better" to have a neutral is when the appliance relies
> on a 110V leg for such things as timers, etc. Returning back to the box
> separately is meaningless. You are equally safe, equally beneficial,
> equally proper by using the three wire configuration as depicted in the
> second example.
By the same reasoning one could argue that there is no reason to have a
ground pin on a 120V appliance.
The separation of neutral and ground gives additional protection against
a fault in the neutral wiring, given that it's not practical for a
metal-bodied stove to be double-insulated.
Chris
On Tue, 13 Nov 2007 17:13:41 -0600, Tom Veatch wrote:
>On Tue, 13 Nov 2007 11:41:36 -0600, Frank Boettcher
><[email protected]> wrote:
>
>>
>>Well, cabinet trim went fine, range fits and is centered (probably
>>should have greased the sides a bit goilg in) currently wiring the new
>>range.
>>
>>romex into the 50 Amp wall plug is three wire, which was code
>>acceptable then and now for reinstallation. However, old range was
>>wired with a four wire plug. Nuetral and ground are tied together in
>>the male end of the plug (which I am reusing).
>>
>>four wire hookup calls for hooking up black, white (nuetral) and red
>>on the terminal block and *removing* a bonding strap from the ground
>>screw to the nuetral terminal on the ground, then attaching the ground
>>wire to the now chassis only ground screw.
>>
>>Three wire hook up calls for black, white (nuetral) and red, no ground
>>wire and leaving the bonding strap in place.
>>
>>I'm going to assume that the former is better despite the fact there
>>is no separate nuetral and ground returning to the box, they are at
>>least separate leaving the appliance.
>>
>>Or maybe it doesn't matter?
>>
>>Frank
>
>
>Assuming the range requires a 110 leg, a neutral is required. Current
>code requires a ground wire separate from the neutral which means
>under today's rules, wiring the range would require a 4-wire (3
>conductor + ground) cable.
Yep, I'm aware of that. The installation instruction even refers to
it. But also refers to the reinstallation being allowable as a three
wire.
>
>The three wire hookup you describe, bonding neutral and ground at the
>plug, violates the code requirement that the grounding wire not carry
>current during normal operation since bonding causes the neutral and
>ground to become a common conductor.
>
>However, if, as you state, the 3-wire installation was per code at the
>time of the original installation and your local jurisdiction doesn't
>require that the installation be brought up to current code
>requirements on re-installation, you should be good to go. It does
>seem a little strange to me that a 4 wire receptacle would be
>permitted in a 3 wire installation. Could be very misleading to all
>who come later.
>
I may have confused with my terminology. The receptacle was three
wire, but the old unit was hooked up as four wire. And it was
confusing to me. I actually took the male plug (three wire
configuration but four wires going in) apart to determine what was
going on. Only thing I can think of is that the old unit did not
have a ground bond, chassis to terminal block.
As far as the 110 requirement, I always thought the lights, timers,
etc. were on a 110 leg. Is that not the case?
>
>Tom Veatch
>Wichita, KS
>USA
In article <[email protected]>, Frank Boettcher <[email protected]> wrote:
>I may have confused with my terminology. The receptacle was three
>wire, but the old unit was hooked up as four wire. And it was
>confusing to me. I actually took the male plug (three wire
>configuration but four wires going in) apart to determine what was
>going on. Only thing I can think of is that the old unit did not
>have a ground bond, chassis to terminal block.
>
>As far as the 110 requirement, I always thought the lights, timers,
>etc. were on a 110 leg. Is that not the case?
They are, which is why you have to have at least three wires for it to work.
The heating elements will run just fine with only two.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
"Frank Boettcher" <[email protected]> wrote in message
news:[email protected]...
>
> four wire hookup calls for hooking up black, white (nuetral) and red
> on the terminal block and *removing* a bonding strap from the ground
> screw to the nuetral terminal on the ground, then attaching the ground
> wire to the now chassis only ground screw.
>
> Three wire hook up calls for black, white (nuetral) and red, no ground
> wire and leaving the bonding strap in place.
>
> I'm going to assume that the former is better despite the fact there
> is no separate nuetral and ground returning to the box, they are at
> least separate leaving the appliance.
>
The only time it's "better" to have a neutral is when the appliance relies
on a 110V leg for such things as timers, etc. Returning back to the box
separately is meaningless. You are equally safe, equally beneficial,
equally proper by using the three wire configuration as depicted in the
second example.
--
-Mike-
[email protected]
On Wed, 14 Nov 2007 08:31:26 -0600, Frank Boettcher
<[email protected]> wrote:
...
>As far as the 110 requirement, I always thought the lights, timers,
>etc. were on a 110 leg. Is that not the case?
That is the typical case, and the reason that a neutral conductor is
required - or, I guess in your case, a combined neutral/ground
conductor.
Tom Veatch
Wichita, KS
USA
On Tue, 13 Nov 2007 11:41:36 -0600, Frank Boettcher
<[email protected]> wrote:
>
>Well, cabinet trim went fine, range fits and is centered (probably
>should have greased the sides a bit goilg in) currently wiring the new
>range.
>
>romex into the 50 Amp wall plug is three wire, which was code
>acceptable then and now for reinstallation. However, old range was
>wired with a four wire plug. Nuetral and ground are tied together in
>the male end of the plug (which I am reusing).
>
>four wire hookup calls for hooking up black, white (nuetral) and red
>on the terminal block and *removing* a bonding strap from the ground
>screw to the nuetral terminal on the ground, then attaching the ground
>wire to the now chassis only ground screw.
>
>Three wire hook up calls for black, white (nuetral) and red, no ground
>wire and leaving the bonding strap in place.
>
>I'm going to assume that the former is better despite the fact there
>is no separate nuetral and ground returning to the box, they are at
>least separate leaving the appliance.
>
>Or maybe it doesn't matter?
>
>Frank
Assuming the range requires a 110 leg, a neutral is required. Current
code requires a ground wire separate from the neutral which means
under today's rules, wiring the range would require a 4-wire (3
conductor + ground) cable.
The three wire hookup you describe, bonding neutral and ground at the
plug, violates the code requirement that the grounding wire not carry
current during normal operation since bonding causes the neutral and
ground to become a common conductor.
However, if, as you state, the 3-wire installation was per code at the
time of the original installation and your local jurisdiction doesn't
require that the installation be brought up to current code
requirements on re-installation, you should be good to go. It does
seem a little strange to me that a 4 wire receptacle would be
permitted in a 3 wire installation. Could be very misleading to all
who come later.
Tom Veatch
Wichita, KS
USA
Code doesn't allow the nuetral (grounded conductor) and the ground
(grounding conductor) to be tied together. However in past codes
there have been exceptions for ranges which allowed the grounded and
grounding conductor to be tied together on ranges and I think dryers.
Its been so long since I've done residentual I'm not sure if it still
exists. If I get a chance I'll check the code book.
Mike M
On Tue, 13 Nov 2007 11:41:36 -0600, Frank Boettcher
<[email protected]> wrote:
>
>Well, cabinet trim went fine, range fits and is centered (probably
>should have greased the sides a bit goilg in) currently wiring the new
>range.
>
>romex into the 50 Amp wall plug is three wire, which was code
>acceptable then and now for reinstallation. However, old range was
>wired with a four wire plug. Nuetral and ground are tied together in
>the male end of the plug (which I am reusing).
>
>four wire hookup calls for hooking up black, white (nuetral) and red
>on the terminal block and *removing* a bonding strap from the ground
>screw to the nuetral terminal on the ground, then attaching the ground
>wire to the now chassis only ground screw.
>
>Three wire hook up calls for black, white (nuetral) and red, no ground
>wire and leaving the bonding strap in place.
>
>I'm going to assume that the former is better despite the fact there
>is no separate nuetral and ground returning to the box, they are at
>least separate leaving the appliance.
>
>Or maybe it doesn't matter?
>
>Frank