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Russell Melville
11-07-2015, 05:30 PM
Pretty sure this aint legal. The lugs at the top are tapped with 12 gauge wire to the breaker at the right of the panel (could that be considered a remote panel) that is used for the water pump, which is 20 amp. Main service disconect is the 100 amp breaker at the top.

Thanks, Russ

Jerry Peck
11-07-2015, 05:40 PM
Pretty sure this aint legal.

Yep, you be right. :)

The only breaker protecting those #12 conductors is that 100 amp main - not good.

That would be in addition to the fact that those top main lugs are not likely listed for #12 size conductors. :(

Russell Melville
11-07-2015, 06:03 PM
Thanks for the quick reply. Just what are those lugs for, if not to tap off?

John Kogel
11-07-2015, 06:16 PM
Thanks for the quick reply. Just what are those lugs for, if not to tap off?Those lugs would be used if the panel was being fed by a disconnect, a main breaker upstream. From that main breaker panel they would run feeders to each of the bus bars.

In this case, they have installed a main breaker and run the feeders to it, so we say they are back-feeding the panel through that breaker.

Russell Melville
11-07-2015, 06:26 PM
So why didn't they use the main lugs instead of backfeeding? There is no main disconnect upstream from the panel.

Jim Port
11-07-2015, 07:24 PM
The backfed breaker is the disconnect.

Jerry Peck
11-07-2015, 07:27 PM
So why didn't they use the main lugs instead of backfeeding? There is no main disconnect upstream from the panel.

Because that panel is a MLO (Main Lug Only) panel and there is no place for a main other than to back feed a main.

A back fed main also requires additional securing so it cannot just be pulled out (the live service entrance ends of the breaker could be quite deadly if that was done. Usually, when a breaker is pulled out, it is dead as it is fed from the bus bar it was pulled from. With a back fed main, it is fed from the conductors, pulling it out exposes the live breaker contacts (potentially live as even if the breaker is turned off, the handle could get bumped back on, and even the terminals the service entrance conductor will be live ... even with the breaker off.

Russell Melville
11-07-2015, 07:51 PM
so what the heck do they have the lugs at the top for, just to tempt some hack as in this case?, If your saying you can't use them for the se wires.

- - - Updated - - -

ok, i just read johns post, it sounds like if it is used as a remote it is ok to use those lugs.

Jim Robinson
11-08-2015, 08:07 AM
For my own education, would that not be considered a feeder tap situation? No raceway present, but other than that it seems like it would.

Jerry Peck
11-08-2015, 04:25 PM
For my own education, would that not be considered a feeder tap situation? No raceway present, but other than that it seems like it would.

Jim,

That's not a feeder tap because it taps from the bus bar and not from a feeder. If the tap was made from a feeder, the feeder it was tapped from would be protected, then the feeder tap (meeting all the specified conditions) would only require the overcurrent protection at its load end.

I looked through all the taps and that does not fall under any of the tap descriptions I found.

Steve Koszuta
11-13-2015, 01:49 PM
Jim,

That's not a feeder tap because it taps from the bus bar and not from a feeder. If the tap was made from a feeder, the feeder it was tapped from would be protected, then the feeder tap (meeting all the specified conditions) would only require the overcurrent protection at its load end.

I looked through all the taps and that does not fall under any of the tap descriptions I found.

It IS considered a "feeder tap" because it is tapped from a feeder (buss bars) protected by the 100A main breaker.

the 10 foot tap rule applies because the load the #12's supply, is protected by a 20A breaker (the sidecar panel).

However the lugs are most likely not rated for #12's.

Jerry Peck
11-13-2015, 02:33 PM
It IS considered a "feeder tap" because it is tapped from a feeder (buss bars) protected by the 100A main breaker.

the 10 foot tap rule applies because the load the #12's supply, is protected by a 20A breaker (the sidecar panel).

However the lugs are most likely not rated for #12's.

The bus bars are 'part of' the service equipment and thus are not feeders.

Feeders are 'between the service equipment and the last branch circuit overcurrent device'.

Those are tapped off the service equipment, not tapped off a feeder.

I look forward to some of the electrical contractors here to definitively clear up the 'what is a feeder and what is not issue', with a code reference. The bus bars in the panel are not, from everything I have ever heard, 'feeders'.

Rollie Meyers
11-13-2015, 11:58 PM
Because that panel is a MLO (Main Lug Only) panel and there is no place for a main other than to back feed a main.

A back fed main also requires additional securing so it cannot just be pulled out (the live service entrance ends of the breaker could be quite deadly if that was done. Usually, when a breaker is pulled out, it is dead as it is fed from the bus bar it was pulled from. With a back fed main, it is fed from the conductors, pulling it out exposes the live breaker contacts (potentially live as even if the breaker is turned off, the handle could get bumped back on, and even the terminals the service entrance conductor will be live ... even with the breaker off.

That requirement came out in the 1990 NEC, and only applies to plug in style breakers, so if the panel was installed before the adoption of that edition, it complies with the code of the time, and if it's a old ITE Pushmatic panel with a back fed main it complies with current code.


http://i197.photobucket.com/albums/aa308/RFM959/IMG_0240_zps6a7c4f8e.jpg (http://s197.photobucket.com/user/RFM959/media/IMG_0240_zps6a7c4f8e.jpg.html)

The backfed main in that panel does not require a hold down either.... :p

Jerry Peck
11-14-2015, 07:26 AM
That requirement came out in the 1990 NEC, and only applies to plug in style breakers, so if the panel was installed before the adoption of that edition, it complies with the code of the time, and if it's a old ITE Pushmatic panel with a back fed main it complies with current code.
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The backfed main in that panel does not require a hold down either.... :p

For home inspectors, that likely falls in the same category as ... guardrails with 12 inch baluster spacing ... stair with 9 inch risers ... no GFCI protection on 2-wire K&T ...

... current nationally accepted safety standards NOW recognize those items as not being safe ... which is because, over time, they have proven themselves as not being safe ... :p

Just because you are standing next to a 150 year old fire-breathing dragon of a furnace which has never killed anyone does not mean it is 'safe' --- it's 'unsafeness' (is that a word?) has been shown.

david shapiro
11-14-2015, 11:09 AM
... current nationally accepted safety standards NOW recognize those items as not being safe ... which is because, over time, they have proven themselves as not being safe ... :p

Just because you are standing next to a 150 year old fire-breathing dragon of a furnace which has never killed anyone does not mean it is 'safe' --- it's 'unsafeness' (is that a word?) has been shown.


Equally important to my (not a home inspector) mind is the fact that the NM is highly unlikely to have been installed under a permit and inspected by the AHJ. While I realize that HIs focus on safety more than legality, indications that something was installed illegally and probably ignorantly suggest that the parts of the job you haven't seen may also have been installed ignorantly.

Any doubt about the lugs having been listed for use with 12AWG conductors probably can be resolved simply by looking at the panel label, so long as that hasn't been removed or destroyed. In ITE residential panels, I believe the schematic/instruction sheet is glued on the inside of the door, readily accessible.