hotwire2006
Member
I have found that code 408-15 is not in the new 2011 code which stated the number of ciriuits in a panel. Is this code somewhere else
panels
- Thread starter hotwire2006
- Start date
- Status
- Location
- Massachusetts
No, the limits have been removed.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Not completely, I think.
408.36Exception No. 2: Individual protection shall not be required
for a panelboard protected on its supply side by two
main circuit breakers or two sets of fuses having a combined
rating not greater than that of the panelboard. A
panelboard constructed or wired under this exception shall
not contain more than 42 overcurrent devices. For the purposes
of determining the maximum of 42 overcurrent devices,
a 2-pole or a 3-pole circuit breaker shall be considered
as two or three overcurrent devices, respectively.
kwired
Electron manager
- Location
- NE Nebraska
Sounds like it is describing a split bus panel with a main for each section to me.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
jwelectric
Senior Member
- Location
- North Carolina
Ever seen a fuse panel with two sets of 60 amp fuses? Most were set up where one set controlled the plug fuses and the other controlled a range. Pull off the lights and still cook or the other way around.
Sometimes one set of pull outs would control one panel and the other another panel.
Sometimes one set of pull outs would control one panel and the other another panel.
Bill Annett
Senior Member
- Location
- Wheeling, WV
- Occupation
- Retired ( 2020 ) City Electrical inspector
Good Morning. To me it sounds like a Main Lug Only panel and it would be limited to 42 over current devices.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
If you are talking to me, nope.
But my background is maybe 20% resi and of that 80% was new construction of apartments and such.
I have only seen K&T twice in my life, never touched it, and have never seen small, #12-10, AL branch circuits.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
I do not believe that describes a MLO panel as a general rule.
kwired
Electron manager
- Location
- NE Nebraska
A main lug only panel would require individual overcurrent protection (unless it is acceptable for use as service equipment with 6 mains). There is no limit to 42 overcurrent devices (since the adoptioin of 2008 NEC) except for the mentioned exception. So far nobody can give an example of when/where/how this exception applies.
- Location
- Massachusetts
I know I cannot.
jwelectric
Senior Member
- Location
- North Carolina
I am sorry I was addressing the forum in general making a statement concerning the Exception where there would be two mains in one panel. Back in my first days it was a general installation in a single family dwelling.
A few days ago I was talking with a group of electricians and inspectors. The subject went in the direction of the type of systems they had seen. The one thing that I walked away from that discussion with was the knowledge that both electricians and inspectors have limits to the type of electrical installations that they are familiar with. Some of the highest license and certificate holders in the group had never had any experience with knob and tube installations. One of the electricians with more than 10 years of experience had done nothing but residential installations but had never seen knob and tube except in pictures. He also said he didn?t think he could bend a 90 in a piece of EMT.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Yeah, there are lots of things I have never seen or worked on that I only know of because of this forum. 5 years ago I would have freaked if I came across an ungrounded or corner grounded Delta.
I will easily admit that most of code knowledge and many installs/materials/methods/etc that I can talk about now I learned from the members here. I have always said how grateful I am to be here.
College was great for learning math and theory, but they do not teach a lot of the good stuff.
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resistance
Senior Member
- Location
- WA
In the case involving 408.36. It states you can protect a panel with an OCPD that is not rated over the panel. They allow it to be located inside the panel cabinet, or anywhere on the supply side of the panel---allowing us to supply a panel with a main inside the cabinet (Service rated), or overcurrent protection can be installed remotely to protect the panel feeders. Either way, the OCP can?t exceed the rating of the panel. Example would be a remote OCPD@ 100amps feeding a MLO panel rated for 200amps<<<This example meets the intent. Or a 200Amp service rated panel in general--obviously this meets the intent. But the exception says: If you decide to use a remote OCPD on the supply side of the panel, then you are limited to 42 OCPD?s. In a nut shell: A Main breaker panel has no limits, but if you decide to install OCP on the supply side of the panel, then you are limited to 42 OCPD?s.
Unless they're 70 some years old, how can they have experience with Knob and Tube?
There are still houses around that have it, and it works.
That's not what I said.
My comment was to the previous comment of few (or none) having experience with K&T.
Knob and tube haven't been used for least 50 years, so unless one is 70+ years old, how does one has experience with knob and tube?
gadfly56
Senior Member
- Location
- New Jersey
- Occupation
- Professional Engineer, Fire & Life Safety
Usually by ripping it out. Until I did a service upgrade on my last home, there was K&T running across the basement ceiling. My father-in-law is 6'7", and I had to remind him to be careful walking around the basement when we had a project down there.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
Depends on where you live.
While the last time i worked on K&T was back in 1978, I am still in my 50's.
- Status