"bud--" wrote in message eb.com...
On 1/14/2014 12:51 AM, Guv Bob wrote:
wrote in message ...
On Mon, 13 Jan 2014 20:48:27 -0500,
wrote:

John Grabowski posted for all of us...

And I know how to SNIP


All the ceiling lights in the house started flickering intermittently, as if
there is a loose connection in the circuit. It's just the light - wall
receptacles are fine.

It is not happening all the time or at a particular time of day. My first
guess was a loose connection at the circuit breaker panel, but all the
connections there are good, and the breaker is fully on.

I know this is not much info, but all I have at this point. I don't think
we have rats, but I can picture a big fat rat chewing on a cable in the
attic.

For the electrical folks, how would you go about troubleshooting this?

Thanks in advance.

Bob

===
Photos of the panel:

View from Left:
http://imageshack.com/a/img560/852/xvkt.jpg
The 2 light circuits are on the same dual breaker module.

View from Right:
http://imageshack.com/a/img856/8070/c7xk.jpg


*The circuit breaker for ceiling lights 1 seems to have some discoloration
on the busbar above the wire terminal screw. There is also a slight
discoloration on the white wire in front of it indicating that it was
exposed to excessive heat. Siemens makes replacement Pushmatic circuit
breakers. You can get them at an electrical supply that is a Siemens
distributor.

Here is an example of the replacement, but I don't recommend buying a used
product: http://www.ebay.com/itm/like/220858664088?lpid=82

It may just my vision but are the wires inserted
under the screws on the proper side? Hard for me
to see...
There are multiple wires under several screws - which I believe is
against code.

I could be wrong, but I believe NEC allows for 2 wires per connection for panels.


The NEC allows more than 1 wire on a breaker only if the breaker was
tested that way. The manufacturer indicates if 2 wires can be used.
SquareD pu to 30A is the only one I am aware of that allows 2 wires.
Those breakers are made to apply pressure to both wires. I don't see a
similar feature on the breakers in the picture.

But I only see one wire per terminal.

Some panels were also tested for 2 wires on a ground connection - the
label will say if it is allowed.

Two wires are not allowed on neutral connections.

Shazam! Thanks Bud! I learned something new today... all that reading has made me HONGRY. Lunch break!

http://www.ecmag.com/section/systems...iring-and-more

http://www.structuretech1.com/2011/0...pped-neutrals/
This has been a requirement of UL 67 for a long time, but was spelled out in the NEC in 2002.

http://ecatalog.squared.com/pubs/Ele...0100DB0705.pdf

The new material in 2002 edition appears in 408.21 and reads like this: "Grounded Conductor Terminations: Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor." For the 2005 edition, the same words appear in 408.41. - See more at: http://www.ecmag.com/section/systems...Q1FQJb.dpufThe new material in 2002 edition appears in 408.21 and reads like this: "Grounded Conductor Terminations: Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor." For the 2005 edition, the same words appear in 408.41. - See more at: http://www.ecmag.com/section/systems...Q1FQJb.dpufThe new material in 2002 edition appears in 408.21 and reads like this: "Grounded Conductor Terminations: Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor." For the 2005 edition, the same words appear in 408.41. - See more at: http://www.ecmag.com/section/systems....ZbQ1FQJb.dpuf

On Tue, 14 Jan 2014 12:37:18 -0600, SteveF wrote:

On 1/13/2014 10:15 PM, wrote:

There are multiple wires under several screws - which I believe is
against code.


Using multiple wires on approved terminals is allowed. Ever seen a
back wired Spec grade Leviton receptacle or switch? Many terminals
allow for at least two wires. Some terminals allow for more.

Pretty much every relay base I ever installed allowed two wires per
terminal. Some barrel type terminals allow for more than two. This
is not common in residential applications, though. Two is always
a max for me. Wire gauge and cross sectional allowance of the
terminal are the main factor.
Code specifically prohibits 2 neutrals on the same screw on the
neutral bus of a power distribution panel.
On back-wired spec grade outlets the wires are clamped between 2
plates - which are compressed by a screw. In a distribution panel the
screw generally pushes directly on the wire, forcing it against the
side of the hole in the bus. Totally different animals.

All the ceiling lights in the house started flickering
intermittently, as if
there is a loose connection in the circuit. It's just the light -
wall
receptacles are fine.

It is not happening all the time or at a particular time of day. My
first
guess was a loose connection at the circuit breaker panel, but all
the
connections there are good, and the breaker is fully on.

I know this is not much info, but all I have at this point. I don't
think
we have rats, but I can picture a big fat rat chewing on a cable in
the
attic.

For the electrical folks, how would you go about troubleshooting
this?

Thanks in advance.

Bob

===
Photos of the panel:

View from Left:
http://imageshack.com/a/img560/852/xvkt.jpg
The 2 light circuits are on the same dual breaker module.

View from Right:
http://imageshack.com/a/img856/8070/c7xk.jpg


*The circuit breaker for ceiling lights 1 seems to have some
discoloration
on the busbar above the wire terminal screw. There is also a slight
discoloration on the white wire in front of it indicating that it was
exposed to excessive heat. Siemens makes replacement Pushmatic
circuit
breakers. You can get them at an electrical supply that is a Siemens
distributor.

Here is an example of the replacement, but I don't recommend buying a
used
product: http://www.ebay.com/itm/like/220858664088?lpid=82

It may just my vision but are the wires inserted
under the screws on the proper side? Hard for me
to see...
There are multiple wires under several screws - which I believe is
against code.

I could be wrong, but I believe NEC allows for 2 wires per connection
for panels.


The NEC allows more than 1 wire on a breaker only if the breaker was
tested that way. The manufacturer indicates if 2 wires can be used.
SquareD pu to 30A is the only one I am aware of that allows 2 wires.
Those breakers are made to apply pressure to both wires. I don't see a
similar feature on the breakers in the picture.

But I only see one wire per terminal.

Some panels were also tested for 2 wires on a ground connection - the
label will say if it is allowed.

Two wires are not allowed on neutral connections.

And the picture clearly shows several instances.


*This panel installation is prehistoric to todays code. At the time this
was originally installed it may have been permitted to have multiple wires
under one screw. Many of the older panels that I run into barely have
enough screw terminals in them for one wire per screw so I guess it was
allowed.

Currently it is one neutral wire per screw, but ground wires are according
to the label in the panel.

On Tue, 14 Jan 2014 18:12:28 -0500, "John Grabowski"
wrote:

All the ceiling lights in the house started flickering
intermittently, as if
there is a loose connection in the circuit. It's just the light -
wall
receptacles are fine.

It is not happening all the time or at a particular time of day. My
first
guess was a loose connection at the circuit breaker panel, but all
the
connections there are good, and the breaker is fully on.

I know this is not much info, but all I have at this point. I don't
think
we have rats, but I can picture a big fat rat chewing on a cable in
the
attic.

For the electrical folks, how would you go about troubleshooting
this?

Thanks in advance.

Bob

===
Photos of the panel:

View from Left:
http://imageshack.com/a/img560/852/xvkt.jpg
The 2 light circuits are on the same dual breaker module.

View from Right:
http://imageshack.com/a/img856/8070/c7xk.jpg


*The circuit breaker for ceiling lights 1 seems to have some
discoloration
on the busbar above the wire terminal screw. There is also a slight
discoloration on the white wire in front of it indicating that it was
exposed to excessive heat. Siemens makes replacement Pushmatic
circuit
breakers. You can get them at an electrical supply that is a Siemens
distributor.

Here is an example of the replacement, but I don't recommend buying a
used
product: http://www.ebay.com/itm/like/220858664088?lpid=82

It may just my vision but are the wires inserted
under the screws on the proper side? Hard for me
to see...
There are multiple wires under several screws - which I believe is
against code.

I could be wrong, but I believe NEC allows for 2 wires per connection
for panels.


The NEC allows more than 1 wire on a breaker only if the breaker was
tested that way. The manufacturer indicates if 2 wires can be used.
SquareD pu to 30A is the only one I am aware of that allows 2 wires.
Those breakers are made to apply pressure to both wires. I don't see a
similar feature on the breakers in the picture.

But I only see one wire per terminal.

Some panels were also tested for 2 wires on a ground connection - the
label will say if it is allowed.

Two wires are not allowed on neutral connections.

And the picture clearly shows several instances.


*This panel installation is prehistoric to todays code. At the time this
was originally installed it may have been permitted to have multiple wires
under one screw. Many of the older panels that I run into barely have
enough screw terminals in them for one wire per screw so I guess it was
allowed.

Currently it is one neutral wire per screw, but ground wires are according
to the label in the panel.
It has not been allowed since the early '60s for sure. Panels with
low numbers of neutral connections generally also had low number of
circuits.

As far as grounds, it was acceptable when grounds first came into
common use to twist them all together and fasten them to ONE lug.
Many panels at that time had no ground buss at all.

On 1/14/2014 5:12 PM, John Grabowski wrote:
All the ceiling lights in the house started flickering
intermittently, as if
there is a loose connection in the circuit. It's just the light -
wall
receptacles are fine.

It is not happening all the time or at a particular time of day.
My first
guess was a loose connection at the circuit breaker panel, but
all the
connections there are good, and the breaker is fully on.

I know this is not much info, but all I have at this point. I
don't think
we have rats, but I can picture a big fat rat chewing on a cable
in the
attic.

For the electrical folks, how would you go about troubleshooting
this?

Thanks in advance.

Bob

===
Photos of the panel:

View from Left:
http://imageshack.com/a/img560/852/xvkt.jpg
The 2 light circuits are on the same dual breaker module.

View from Right:
http://imageshack.com/a/img856/8070/c7xk.jpg


*The circuit breaker for ceiling lights 1 seems to have some
discoloration
on the busbar above the wire terminal screw. There is also a slight
discoloration on the white wire in front of it indicating that it
was
exposed to excessive heat. Siemens makes replacement Pushmatic
circuit
breakers. You can get them at an electrical supply that is a Siemens
distributor.

Here is an example of the replacement, but I don't recommend
buying a used
product: http://www.ebay.com/itm/like/220858664088?lpid=82

It may just my vision but are the wires inserted
under the screws on the proper side? Hard for me
to see...
There are multiple wires under several screws - which I believe is
against code.

I could be wrong, but I believe NEC allows for 2 wires per
connection for panels.


The NEC allows more than 1 wire on a breaker only if the breaker was
tested that way. The manufacturer indicates if 2 wires can be used.
SquareD pu to 30A is the only one I am aware of that allows 2 wires.
Those breakers are made to apply pressure to both wires. I don't see a
similar feature on the breakers in the picture.

But I only see one wire per terminal.

Some panels were also tested for 2 wires on a ground connection - the
label will say if it is allowed.

Two wires are not allowed on neutral connections.

And the picture clearly shows several instances.

Was in a post a lot further back than I looked.


*This panel installation is prehistoric to todays code.

I haven't seem a Pushamatic breaker for a real long time. I am really
not impressed by the bus sitting exposed right below where you stuff the
wire into the breaker.

At the time this
was originally installed it may have been permitted to have multiple
wires under one screw. Many of the older panels that I run into barely
have enough screw terminals in them for one wire per screw so I guess it
was allowed.

Currently it is one neutral wire per screw, but ground wires are
according to the label in the panel.

The oldest version of the NEC I have (1968) requires terminals to be
listed for more than one wire to be able to land more than one wire in a
terminal. Would be interesting if there was no such requirement when the
panel was installed, or if UL then allowed doubling up neutrals (as you
wrote), or if the requirement was just ignored. I have seen neutrals and
the ground for that circuit in the same panel terminal.

The same requirement is in the NEC now at 110.14-A. As in 1968, it does
not allow doubling up wires on breakers or the neutral/ground bar (or
elsewhere) unless the terminals are listed for multiple wires. Because
of the UL standard for panels, doubling up of neutral wires is never
allowed (also in the NEC).

Well, the lights started flickering again. In attached, CB 1 & 3 are a signal unit - tandem I think is the term. I removed them, cleaned all the contacts and checked all the wiring connections and all are fine. After that, no flickering for a few weeks. Now it started again this week. Connections are still tight.


Looks like you have to pay to post images at imageshack.us now. If anyone knows somewhere else, I can post an image for this there. Meanwhile, it's posted at alt.binaries.schematics.electronics and alt.binaries.schematics.electronic.

CB #9, receptacle near the door has a lamp plugged into it and it also flickers when the ceiling lights do. So that probably elimates CB 1&3 as the problem. Also, it might be good to say that no appliances or heavy power users are running at the time of the flickering. I have looked for a common activity, but they flicker night or day, and whether anything else is running or not.

No other devices are flickering. Wind doesn't make any difference,. The ceiling light/fan in slot #8 doesn't flicker, nor do any other lamps plugged into receptacles.

Any other ideas what might be the problem before I go out and buy a new CB?

Thanks fellers!

Bob