|
Home > Archive > Building and Construction > June 2006 > Need Help Urgently! Surface mount electric panel
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
Need Help Urgently! Surface mount electric panel
|
|
|
| Hi,
I have installed a surface mount 125 A combination meter main. I have
brought all my home runs, 14 of them, all except 2 are 14-2 NM cables
through two 1 1/2" knock outs from the back into the panel with a chase
nipple. Before entering the chase nipple all cables are stapled to the
stud where the panel is mounted. NOW, here is my problem, the inspector
now all of the sudden doesn't accept that (used to be accepted by him
and others just weeks ago) tells me to run them through a gutter and no
more than 2 NMs in a single connector and refers to article 312.5 in
NEC.
I am hoping for help here, there are only few knock outs at the bottom
of the panel, this a Murray 125 A surface mount panel (JA2442B1125SEC)
and of course being a surface mount all are outside. My only other
option is to have min. 7 knock outs in the back of the panel, that is
to punch them, which might be another problem. The inspector could
claim that I am not allowed to punch holes there. Siemens/Murray are of
absolutly of NO help. I will think twice before using their stuff
again.
How are you guys installing these panels with home runs or having NMs
coming into them, they got place for 24 full size breakers. Somebody
must have thought about this, it can't be that every of these panels
needs a gutter. Again your help is very mich apprerciated. By the way
the NEC referrence is the one on 2004.
Thanks
JJ
PS: someone else had this question before but I couldn't find any
answer to it.
"While pawing through the 1999 NEC (the one the county inspects to) I
found
that 373-5(c) no longer allows the arrangement in the current box, all
of
the NM cables coming in through a single opening with a bushing in the
back
of the box.
So two questions, please.
First, what is the preferred method for bringing NM loads into a box
like
this? 20 or so individual cable clamps seems bad, and I don't get how
the
exception for one or more 18" conduits into the top of the panel is
supposed to work."
| |
| Phil Scott 2006-06-13, 2:21 am |
|
"JJ" <jj98_99@yahoo.com> wrote in message
news:1150174660.695936.228070@h76g2000cwa.googlegroups.com...
> Hi,
>
> I have installed a surface mount 125 A combination meter
> main. I have
> brought all my home runs, 14 of them, all except 2 are 14-2
> NM cables
> through two 1 1/2" knock outs from the back into the panel
> with a chase
> nipple. Before entering the chase nipple all cables are
> stapled to the
> stud where the panel is mounted. NOW, here is my problem,
> the inspector
> now all of the sudden doesn't accept that (used to be
> accepted by him
> and others just weeks ago) tells me to run them through a
> gutter and no
> more than 2 NMs in a single connector and refers to article
> 312.5 in
> NEC.
>
> I am hoping for help here, there are only few knock outs at
> the bottom
> of the panel, this a Murray 125 A surface mount panel
> (JA2442B1125SEC)
> and of course being a surface mount all are outside. My only
> other
> option is to have min. 7 knock outs in the back of the
> panel, that is
> to punch them, which might be another problem. The inspector
> could
> claim that I am not allowed to punch holes there.
> Siemens/Murray are of
> absolutly of NO help. I will think twice before using their
> stuff
> again.
>
> How are you guys installing these panels with home runs or
> having NMs
> coming into them, they got place for 24 full size breakers.
> Somebody
> must have thought about this, it can't be that every of
> these panels
> needs a gutter. Again your help is very mich apprerciated.
> By the way
> the NEC referrence is the one on 2004.
>
> Thanks
>
> JJ
>
> PS: someone else had this question before but I couldn't
> find any
> answer to it.
>
> "While pawing through the 1999 NEC (the one the county
> inspects to) I
> found
> that 373-5(c) no longer allows the arrangement in the
> current box, all
> of
> the NM cables coming in through a single opening with a
> bushing in the
> back
> of the box.
>
> So two questions, please.
>
> First, what is the preferred method for bringing NM loads
> into a box
> like
> this? 20 or so individual cable clamps seems bad, and I
> don't get how
> the
> exception for one or more 18" conduits into the top of the
> panel is
> supposed to work."
too many conductors through your chase nipple. violates
code... so split them up as the inspector wants... thats how
its been done for years. I dont think as you had them it
was unsafe, for a chase nipple... but it violates code so just
change it...
or you can go into a gutter and make wire nut splices there if
you have to, then up to the bottom of the panel with 3/4"
nipples. none of that should be a problem. ask the inspector
to draw you a sketch of what he wants. He cant be too far
off.
you can punch holes in the back of the panel, but of course
not behind the buss bars or breaker areas etc. you must use
weather tight fittings at those locations if its outside.
Murray is not advising you because they dont need the
liability if you screw it up. its not their job... especially
for the modest profit they make on the equipment.
You have an obligation as the installer to self educate...no
need to whine about these things... life is too short for
that.
by the way, mostly these days we run 12/2 14/2 is not
common these days except on say a branch to a light fixture
etc...certainly not for recepticles etc. your 14 will work,
but those circuits will be tripping if you plug a vacuum
cleaner or power tool into them etc... and cant be used for
an electric space heater even if the wire is rated for 15
amps, thats peak load, continous load rating is more like 12
amps... thats light.
Phil Scott
Phil Scott
Mechanical/ electrical contractor.
>
| |
|
| Hi Phil,
thanks for your advice. I still have a question. Since this is a
surface mount panel, all of the box is outside and how am I have to go
into the box from the bottom? And I have only a few knock outs there,
not the 7 the inspector wants. He says you can not have more than 2 NM
per connector and I have 14 of them. He is just giving me a hard time
and I am looking to see if he is ligit. Everybody I know here in the SF
bay area brings their cables through chase nipples into the panel from
the back. And by the way, I have only 7 NMs in an 1 1/2" chase nipple,
that is less than 30% fill, is that still too much?
Thanks
Phil Scott wrote:[color=darkred]
> "JJ" <jj98_99@yahoo.com> wrote in message
> news:1150174660.695936.228070@h76g2000cwa.googlegroups.com...
>
>
> too many conductors through your chase nipple. violates
> code... so split them up as the inspector wants... thats how
> its been done for years. I dont think as you had them it
> was unsafe, for a chase nipple... but it violates code so just
> change it...
>
> or you can go into a gutter and make wire nut splices there if
> you have to, then up to the bottom of the panel with 3/4"
> nipples. none of that should be a problem. ask the inspector
> to draw you a sketch of what he wants. He cant be too far
> off.
>
> you can punch holes in the back of the panel, but of course
> not behind the buss bars or breaker areas etc. you must use
> weather tight fittings at those locations if its outside.
>
> Murray is not advising you because they dont need the
> liability if you screw it up. its not their job... especially
> for the modest profit they make on the equipment.
>
> You have an obligation as the installer to self educate...no
> need to whine about these things... life is too short for
> that.
>
> by the way, mostly these days we run 12/2 14/2 is not
> common these days except on say a branch to a light fixture
> etc...certainly not for recepticles etc. your 14 will work,
> but those circuits will be tripping if you plug a vacuum
> cleaner or power tool into them etc... and cant be used for
> an electric space heater even if the wire is rated for 15
> amps, thats peak load, continous load rating is more like 12
> amps... thats light.
>
>
>
>
>
>
> Phil Scott
>
>
>
>
>
>
>
>
>
> Phil Scott
> Mechanical/ electrical contractor.
>
>
| |
|
| Dumb question, but here it goes. What's a gutter?
--
remove one of the @'s unless you are a spammer.
"JJ" <jj98_99@yahoo.com> wrote in message
news:1150174660.695936.228070@h76g2000cwa.googlegroups.com...
> Hi,
>
> I have installed a surface mount 125 A combination meter main. I have
> brought all my home runs, 14 of them, all except 2 are 14-2 NM cables
> through two 1 1/2" knock outs from the back into the panel with a chase
> nipple. Before entering the chase nipple all cables are stapled to the
> stud where the panel is mounted. NOW, here is my problem, the inspector
> now all of the sudden doesn't accept that (used to be accepted by him
> and others just weeks ago) tells me to run them through a gutter and no
> more than 2 NMs in a single connector and refers to article 312.5 in
> NEC.
>
> I am hoping for help here, there are only few knock outs at the bottom
> of the panel, this a Murray 125 A surface mount panel (JA2442B1125SEC)
> and of course being a surface mount all are outside. My only other
> option is to have min. 7 knock outs in the back of the panel, that is
> to punch them, which might be another problem. The inspector could
> claim that I am not allowed to punch holes there. Siemens/Murray are of
> absolutly of NO help. I will think twice before using their stuff
> again.
>
> How are you guys installing these panels with home runs or having NMs
> coming into them, they got place for 24 full size breakers. Somebody
> must have thought about this, it can't be that every of these panels
> needs a gutter. Again your help is very mich apprerciated. By the way
> the NEC referrence is the one on 2004.
>
> Thanks
>
> JJ
>
> PS: someone else had this question before but I couldn't find any
> answer to it.
>
> "While pawing through the 1999 NEC (the one the county inspects to) I
> found
> that 373-5(c) no longer allows the arrangement in the current box, all
> of
> the NM cables coming in through a single opening with a bushing in the
> back
> of the box.
>
> So two questions, please.
>
> First, what is the preferred method for bringing NM loads into a box
> like
> this? 20 or so individual cable clamps seems bad, and I don't get how
> the
> exception for one or more 18" conduits into the top of the panel is
> supposed to work."
>
| |
| Phil Scott 2006-06-13, 10:21 pm |
|
"JJ" <jj98_99@yahoo.com> wrote in message
news:1150206815.731918.34560@i40g2000cwc.googlegroups.com...
> Hi Phil,
>
> thanks for your advice. I still have a question. Since this
> is a
> surface mount panel, all of the box is outside and how am I
> have to go
> into the box from the bottom? And I have only a few knock
> outs there,
> not the 7 the inspector wants.
You use a step drill to make the holes. You make sure your
panel is rated for outside use, that its rain tight etc and
installed per the mfgrs instructions.
He says you can not have more than 2 NM
> per connector and I have 14 of them. He is just giving me a
> hard time
He is trying to keep his job by enforcing the code. He is
not giving you a hard time... you are assuming that...if you
bug him though,, THEN he will give you a hard time.
> and I am looking to see if he is ligit. Everybody I know
> here in the SF
> bay area brings their cables through chase nipples into the
> panel from
> the back. And by the way, I have only 7 NMs in an 1 1/2"
> chase nipple,
> that is less than 30% fill, is that still too much?
30% fill is not too much... if you have secured the NM before
it enters the nipple you should not have to clamp it at the
chase nipple... it should be fine.... however the NEC is a
**MINIMUM*** standard... it is totally proper to build to a
higher standard or for the building inspector to demand a
higher standard according to his judgement for any particular
situation, it is his job to see to it that the installation is
safe...
to satisfy him you could go into a rain tight chase mounted
below the box... then make wire nut connections to wire fed
through a single conduit from the chase to the panel, say 1.5"
to the panel...you can come out of the end of the chase and
enter one side of the panel...or with the proper fittings go
from the top of the chase with a short rain tight coupling
directly into the bottom of the panel...whatever the inspector
will approve.
You use a knock out punch or step drill to make the
appropriate sized holes.
Perhaps when he saw all the 14/2 feeding all those receptical
circuits he decided to get picky... that is inherently loopy
especially if you put more than 2 duplex outlets on each 14/2
circuit.
What size wire did you run to any heavy demand electric
appliances, say a drier, electric range or HVAC for
example...did you size the wire for continuous load? Or size
to the wires peak / intermittent load rating?
Phil Scott
>
> Thanks
>
>
>
> Phil Scott wrote:
>
| |
|
| Used in: Many electrical systems, especially those incorporating several
components such as disconnects, inverters, and KWH meters.
AKA: Wireway
It is: A sheet-metal enclosure with removable cover, used for housing and
protecting electrical wiring.
Using gutters is a convenient way to protect electrical wiring from
abrasion, dirt, dust, and water, and route multiple wires from several
electrical components. If I had to pick one wiring enclosure that results in
superclean installation, a gutter would be it.
Gutters are sheet-metal troughs manufactured in 1- to 10-foot (0.3-3 m)
lengths. While 4- and 6-inch (10 and 15 cm)width/depth dimensions are most
common, the width anddepth of the gutter you choose will vary depending on
the size and number of wires being routed through it. Guttersfor both indoor
and outdoor use are available at most electrical supply stores. Outdoor
gutters have waterproofcovers; always use sealing washers on all conduit
fittings entering the gutter to ensure a weather-tight installation.
While gutters are made with regularly spaced knockout holes for
various-sized conduit, they may not accommodate your particular installation
needs. Many installations will require punching or drilling holes in custom
locations along the gutter. A slug-buster (also called a hole punch) is the
best tool for the job. Hole-saw bits manufactured to cut metal also can be
used.
Quoted from:
http://sfgov.org/site/uploadedfiles...ive/m041498.doc
--
Jonny
"Bill" <bargerw@@bellsouth.net> wrote in message
news:n%Ijg.13775$gv2.8473@bignews3.bellsouth.net...
> Dumb question, but here it goes. What's a gutter?
>
> --
> remove one of the @'s unless you are a spammer.
> "JJ" <jj98_99@yahoo.com> wrote in message
> news:1150174660.695936.228070@h76g2000cwa.googlegroups.com...
>
>
|
|
|
|
|