Need some enlightenment

Old building so I have never seen this scenario.

First picture shows main panel. Second shows sub-panel. Why three hot feeds to main and sub-panel?

Just by looking at the wire size…Looks like they’re feeding the main SE with 200 amps and then feeding the LSE (sub-panel) with 100 amps.

Those are 3-phase panels, brother.

Why three phase, ya think? I don’t see any circuits running three phase.

Not sure John…I did notice the one on the upper left of the first image is a 3-pole breaker…could be running something 3 phase I recon…

Why…possibly it was a old commerical building that was reconditioned into a dwelling unit…and never got around to any service issues…

Hey ya Paul your right. I think the place was an old hotel made into condo’s at some point. Honestly, I don’t think that three pole breaker was used, well maybe two of the poles :oops:.


Do the neutral and ground buses need to be isolated in a three phase sub panel? How many conductors to feed a three phase sub-panel.

I’ll pretend I’m Paul for a minute, but I’ll resist the urge to put in LOL’s in weird places and … between thoughts. :mrgreen:

Yes, all sub-panels located in the same building as the service panel, 3 phase or otherwise, need the grounds and neutrals separated. Three-phase just has an extra “hot”, so you’d need 5 conductors to a sub-panel (three hots, neutral, ground), or maybe less the ground if it’s conductors in metallic conduit and the conduit’s being used as the ground. This might be what you have in your image. Hard to say. If it’s all in pipe at the sub-panel, feeder and branch circuits, and the conduit is being used as the ground, you’d really not have a ground bar. Just the metal of the panel can is the “ground bar”, so to speak.

Thanks Paul and Paul. :wink:

lol…thats just my style Marc…just my style…

I know; just teasing.

I remain troubled by the fact that a guy who’s doing what seems like a light commercial inspection seems to be fundamentally unfamiliar with 3-phase. Even if you don’t know how it works, shouldn’t the guy doing the inspection be able to visually recognize the interior of equipment as being 3-phase gear when he’s faced with it? What I mean to say is that it’s not really rare or special in a commercial occupancy. It’s fairly fundamental stuff. What do you think?


I think in this case the setting was ( or used to be an old commerical environment ) converted to dwelling units and was truly a residential inspection for the guy.

I have done quite a few seminars now and I always go into 3 -phase a little…BUT it is important in my mind that they understand that bonding and grounding and the basic principles do not change…just the ungrounded factors ( and they don’t get into balancing and so on )

I think many times if you are not used to 3 phase that just maybe they open a panel and get SPOOKED at what they see quite honestly so I try to break it down in the seminars to loose the MYSTIC of it…because they can inspect it just like any other panel…with regards to the basics.

SO in Johns defense…he was looking at condo’s and expected a normal 120/240 setup…Surprise…not what he got…:slight_smile:

Many inspectors that do light or standard commercial inspections sub out the electrical portion ( not sure why…really not a difficult thing to inspect ) but it happens alot so basically I think it " SHOCKED " him for a lack of a better term and was not expecting it to be 3 phase.

The GREAT part about this is…now JOHN knows Exactly what a 3-phase setup looks like and yet another home inspectors has been educated…

Don’t let it trouble you fella…I encourage the guys to ASK any question regardless of how basic it is or complex so we can break it down, educate from it and in this case…allow hundreds of others to read about it and learn what 3 phase is…if you notice NACHI stands for National Association of Certified Home Inspectors…lol…not Commerical inspectors, while many are doing more and more of them…they are learning as well and in this case JOHN was blind sided by an old commerical to condo renovation that left an old service in place…that simply threw him I am sure…

and I do hear ya…but not real basic for a home inspector who does not see it much or if at all…

DAMN I am long freakin winded…

Add also havering/equivocating, many times.

1 : to use equivocal language especially with intent to deceive
2.) Hem and Haw…I think thats Havering…lol

…I post what I think and stand behind it…:wink:

Again…visit and type in my zipcode…22802 and choose contractor business and tradesman individual and you will see my info…:slight_smile: No electricains in VA go back before 1995…thats when the DPOR was created…those of us licensed by the state back in 1988-89 tested in Richmond but got licenses from the city to which we worked but they were honored statewide…thats why the DPOR took over to simplify the records keeping for VA and well to collect the freakin renewal fee’s as well no doubt.

Actually it is an ART FORM…it’s called being TACTFUL …Understanding their are GREY areas to anything and working with people to work them out, not offend valued members but to educate them instead…I am very GUILTY of that…Sorry

Yep I am still long winded however…ask anyone who attends my seminars ( you know the ones being taught by someone with no workers comp insurance…;)…You will be happy to know I am now down to (1) other apprentice and if things go the way I want it…none by the end of the year…oh I am praying…praying hard but it does leave me doing all the work as I am pricing a blueprint as we speak…Conest Estimation Software is TOOOOO complicated otherwise I would be done…already.




I wasn’t saying anything bad. In this context, havering or equivocating would approximate to rambling or hemming and hawing. Calm down, brother. Go have a smoke, brew, or chocolate bar; whatever does the trick for you.

Thank you Paul for answering the question of “why”.

lol…I ain’t mad fella…just posting information on why I Hem and Haw and ramble and so on…

I am high strung all the time fella…I am never mad or upset…:slight_smile:

and LORD knows you don’t want me eating more chocolate bars…man I would be bouncing off the walls in my office, I already have 6 cups of coffee today.

Why I am high strung…tehehheeh…hell I dont know it is in the birth…I might have been slapped too hard at birth…heck if I know…OPPS…sorry wrong topic…lol