On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "
wrote:

When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.
With switches, the BOX must be grounded - the switch grounds to the
box.

On Oct 5, 7:25*pm, wrote:
On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "

wrote:
When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.

*With switches, the BOX must be grounded - the switch grounds to the
box.

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box? And why would one be different
than the other?

On 10/8/2011 7:03 AM, wrote:
On Oct 5, 7:25 pm, wrote:
On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "

wrote:
When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.

With switches, the BOX must be grounded - the switch grounds to the
box.

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.

2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)

And why would one be different
than the other?

Grounding of switches is to ground any metal plates. It should be quite
difficult to get high ground currents.

Grounding of receptacles is to make a good contact for ground return
currents from devices attached to the receptacle through the receptacle
ground pin.

--
bud--

On Oct 10, 10:45*am, bud-- wrote:
On 10/8/2011 7:03 AM, wrote:





On Oct 5, 7:25 pm, wrote:
On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "

*wrote:
When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.

* With switches, the BOX must be grounded - the switch grounds to the
box.

OK, so now we have the switch grounding question
resolved. * But there was mention of a difference for
receptacles? *So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.


I just installed a Leviton receptacle and 2 Leviton switches, a STSP
and a STDP.

All three devices had a paper disc on 1 screw and a metal bracket that
was riveted to the strap for the other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self grounding" -
assuming the box is grounded, of course.

2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

* 3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)

And why would one be different
than the other?

Grounding of switches is to ground any metal plates. It should be quite
difficult to get high ground currents.

Grounding of receptacles is to make a good contact for ground return
currents from devices attached to the receptacle through the receptacle
ground pin.

--
bud--- Hide quoted text -

- Show quoted text -

On Oct 10, 10:45*am, bud-- wrote:
On 10/8/2011 7:03 AM, wrote:





On Oct 5, 7:25 pm, wrote:
On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "

*wrote:
When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.

* With switches, the BOX must be grounded - the switch grounds to the
box.

OK, so now we have the switch grounding question
resolved. * But there was mention of a difference for
receptacles? *So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.

2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

* 3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)

And why would one be different
than the other?

Grounding of switches is to ground any metal plates. It should be quite
difficult to get high ground currents.

Grounding of receptacles is to make a good contact for ground return
currents from devices attached to the receptacle through the receptacle
ground pin.

--
bud--- Hide quoted text -

- Show quoted text -

Thanks for the explanation Bud. But unless I'm missing
something, at the end of it, the rules for a switch or
a receptacle in a metal box seem the same. Meaning
the switch gets grounded to the metal box via the two
screws that hold it to the box or metal cover too right?

On 10/11/2011 9:47 AM, wrote:
On Oct 10, 10:45 am, wrote:
On 10/8/2011 7:03 AM, wrote:





On Oct 5, 7:25 pm, wrote:
On Wed, 5 Oct 2011 12:30:40 -0700 (PDT), "

wrote:
When using a metal junction box, eg handybox for a switch,
is it acceptable code to:

A - Just ground the metal box and rely on the switch getting
grounded by being fastened to the box

B - Just ground the switch and rely on the box getting
grounded by being fastened to the switch

C - Both must be grounded using wire?

Thanks all.

With switches, the BOX must be grounded - the switch grounds to the
box.

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.

2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)

And why would one be different
than the other?

Grounding of switches is to ground any metal plates. It should be quite
difficult to get high ground currents.

Grounding of receptacles is to make a good contact for ground return
currents from devices attached to the receptacle through the receptacle
ground pin.

--
bud--- Hide quoted text -

- Show quoted text -

Thanks for the explanation Bud. But unless I'm missing
something, at the end of it, the rules for a switch or
a receptacle in a metal box seem the same. Meaning
the switch gets grounded to the metal box via the two
screws that hold it to the box or metal cover too right?

Yes on the switch. The requirements are much tighter for a receptacle.

The requirement for a switch was added fairly recently because with
plastic boxes the switch (and metal plates) are not grounded.
Receptacles in plastic boxes were always required to have a ground wire.

--
bud--

On 10/10/2011 10:17 AM, DerbyDad03 wrote:
On Oct 10, 10:45 am, wrote:
On 10/8/2011 7:03 AM, wrote:

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.


I just installed a Leviton receptacle and 2 Leviton switches, a STSP
and a STDP.

All three devices had a paper disc on 1 screw and a metal bracket that
was riveted to the strap for the other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self grounding" -
assuming the box is grounded, of course.

That is #3 below. Many receptacles (particularly cheap ones) don't have
the metal clip from yoke to screw and you have to remove at least 1 of
the paper discs.


2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)

On Oct 14, 2:01*pm, bud-- wrote:
On 10/10/2011 10:17 AM, DerbyDad03 wrote:





On Oct 10, 10:45 am, *wrote:
On 10/8/2011 7:03 AM, wrote:

OK, so now we have the switch grounding question
resolved. * But there was mention of a difference for
receptacles? *So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws securing the
receptacle strap to the box. Often the screws have a paper or similar
disc on the screws to keep them attached to the loose receptacle - at
least one disc has to be removed.

I just installed a Leviton receptacle and 2 Leviton switches, a STSP
and a STDP.

All three devices had a paper disc on 1 screw and a metal bracket that
was riveted to the strap for the other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self grounding" *-
assuming the box is grounded, of course.

That is #3 below. Many receptacles (particularly cheap ones) don't have
the metal clip from yoke to screw and you have to remove at least 1 of
the paper discs.





2- Receptacle attaches to metal cover on metal box - all I can think of
are for 4" square boxes. Receptacle has to attach to the cover with 2
screws (a few other requirements). Old covers have the receptacle
attached to the cover with one screw.

* *3. "Self grounding" receptacles with a clip from the yoke to the
screws, metal box.

4. In almost all other cases, a ground wire to the receptacle.

(406.11, 250.146)- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

I'm not arguing, just curious...

Why do you need to remove the paper disc?

If the device is tightened securely then there is a grounding path
since the screw head contacts the device and the screw threads contact
the threads of the box. If the box is not tightened securely, then
even if the disc is removed, the connection would still be suspect.

Is removing the disc just so that there is a more contact than just
the screw head and threads?

In ,
DerbyDad03 typed:
On Oct 14, 2:01 pm, bud-- wrote:
On 10/10/2011 10:17 AM, DerbyDad03 wrote:





On Oct 10, 10:45 am,
wrote:
On 10/8/2011 7:03 AM, wrote:

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws
securing the receptacle strap to the box. Often the
screws have a paper or similar disc on the screws to
keep them attached to the loose receptacle - at least
one disc has to be removed.

I just installed a Leviton receptacle and 2 Leviton
switches, a STSP and a STDP.

All three devices had a paper disc on 1 screw and a
metal bracket that was riveted to the strap for the
other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self
grounding" - assuming the box is grounded, of course.

That is #3 below. Many receptacles (particularly cheap
ones) don't have the metal clip from yoke to screw and
you have to remove at least 1 of the paper discs.





2- Receptacle attaches to metal cover on metal box -
all I can think of are for 4" square boxes. Receptacle
has to attach to the cover with 2 screws (a few other
requirements). Old covers have the receptacle attached
to the cover with one screw.

3. "Self grounding" receptacles with a clip from
the yoke to the screws, metal box.

4. In almost all other cases, a ground wire to the
receptacle.

(406.11, 250.146)- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

I'm not arguing, just curious...

Why do you need to remove the paper disc?

If the device is tightened securely then there is a
grounding path since the screw head contacts the device
and the screw threads contact the threads of the box. If
the box is not tightened securely, then even if the disc
is removed, the connection would still be suspect.

Is removing the disc just so that there is a more contact
than just the screw head and threads?

No response from here caand be deemed correct as only your local code
enforcemant offce knows whether they have requiremenrs over & above the NEC
etc.. Check with them for the fnal word regardless of what anyone here tels
you.
--

HTH,

Twayne`

On 10/14/2011 5:00 PM, Twayne wrote:
In ,
typed:
On Oct 14, 2:01 pm, wrote:
On 10/10/2011 10:17 AM, DerbyDad03 wrote:





On Oct 10, 10:45 am,
wrote:
On 10/8/2011 7:03 AM, wrote:

OK, so now we have the switch grounding question
resolved. But there was mention of a difference for
receptacles? So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws
securing the receptacle strap to the box. Often the
screws have a paper or similar disc on the screws to
keep them attached to the loose receptacle - at least
one disc has to be removed.

I just installed a Leviton receptacle and 2 Leviton
switches, a STSP and a STDP.

All three devices had a paper disc on 1 screw and a
metal bracket that was riveted to the strap for the
other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self
grounding" - assuming the box is grounded, of course.

That is #3 below. Many receptacles (particularly cheap
ones) don't have the metal clip from yoke to screw and
you have to remove at least 1 of the paper discs.





2- Receptacle attaches to metal cover on metal box -
all I can think of are for 4" square boxes. Receptacle
has to attach to the cover with 2 screws (a few other
requirements). Old covers have the receptacle attached
to the cover with one screw.

3. "Self grounding" receptacles with a clip from
the yoke to the screws, metal box.

4. In almost all other cases, a ground wire to the
receptacle.

(406.11, 250.146)

I'm not arguing, just curious...

Why do you need to remove the paper disc?

If the device is tightened securely then there is a
grounding path since the screw head contacts the device
and the screw threads contact the threads of the box. If
the box is not tightened securely, then even if the disc
is removed, the connection would still be suspect.

Is removing the disc just so that there is a more contact
than just the screw head and threads?

That's what I think. Previously the code said "direct metal-to-metal
contact between the device yoke and the box". The change to remove at
least one washer clarifies that.

I am not a big fan of self grounding receptacles. Seems like the contact
area is not very large.


No response from here caand be deemed correct as only your local code
enforcemant offce knows whether they have requiremenrs over& above the NEC
etc.. Check with them for the fnal word regardless of what anyone here tels
you.

The usual useless information from Twayne. Congratulations on your
consistent record.

--
bud--

On Oct 17, 1:09*pm, bud-- wrote:
On 10/14/2011 5:00 PM, Twayne wrote:





,
*typed:
On Oct 14, 2:01 pm, *wrote:
On 10/10/2011 10:17 AM, DerbyDad03 wrote:

On Oct 10, 10:45 am,
wrote:
On 10/8/2011 7:03 AM, wrote:

OK, so now we have the switch grounding question
resolved. * But there was mention of a difference for
receptacles? *So, what is the rule for a receptacle
with a metal box?

1. Surface metal box (handybox, ...) with 2 screws
securing the receptacle strap to the box. Often the
screws have a paper or similar disc on the screws to
keep them attached to the loose receptacle - at least
one disc has to be removed.

I just installed a Leviton receptacle and 2 Leviton
switches, a STSP and a STDP.

All three devices had a paper disc on 1 screw and a
metal bracket that was riveted to the strap for the
other screw.

Here's a pic:

http://i.pgcdn.com/pi/75/87/77/758777524_260.jpg

No need to remove a disc as the devices are "self
grounding" *- assuming the box is grounded, of course.

That is #3 below. Many receptacles (particularly cheap
ones) don't have the metal clip from yoke to screw and
you have to remove at least 1 of the paper discs.

2- Receptacle attaches to metal cover on metal box -
all I can think of are for 4" square boxes. Receptacle
has to attach to the cover with 2 screws (a few other
requirements). Old covers have the receptacle attached
to the cover with one screw.

* * 3. "Self grounding" receptacles with a clip from
the yoke to the screws, metal box.

4. In almost all other cases, a ground wire to the
receptacle.

(406.11, 250.146)

I'm not arguing, just curious...

Why do you need to remove the paper disc?

If the device is tightened securely then there is a
grounding path since the screw head contacts the device
and the screw threads contact the threads of the box. If
the box is not tightened securely, then even if the disc
is removed, the connection would still be suspect.

Is removing the disc just so that there is a more contact
than just the screw head and threads?

That's what I think. Previously the code said "direct metal-to-metal
contact between the device yoke and the box". The change to remove at
least one washer clarifies that.

I am not a big fan of self grounding receptacles. Seems like the contact
area is not very large.



No response from here caand be deemed correct as only your local code
enforcemant offce knows whether they have requiremenrs over& *above the NEC
etc.. Check with them for the fnal word regardless of what anyone here tels
you.

The usual useless information from Twayne. Congratulations on your
consistent record.

--
bud--- Hide quoted text -

- Show quoted text -

But his presentation was so elegant that it must be correct.

caand
enforcemant
offce
requiremenrs
over&
fnal
tels

How could a paragraph with an 18% error rate *not* be considered
credible?