Bulldog Pushmatic panel main bus bar terminals

At least we agree on the “no” bit Jeff :wink:

BTW: I read Pauls opinion, then I took 2 advil and laid down for a while :mrgreen:

Regards

Gerry

lol…the key is…when you woke UP did you have a different opinion…:wink:

Maybe mate :wink:

You gotta read the tread (at least look at the pics) and give us your opinion.

Jeff and I seldom differ on these issues, but this is an odd set up

Gerry

I will accept Paul’s opinion as the Supreme Law of the Land :wink:

LOL, so will I mate, I mean who can argue with the Grand Master of Electrical Guruism :mrgreen:

Now if he’ll just get off the fence, put the splinters out from his arse and give us a nice clean definative answer (that proves I’m right) we can all move on :twisted:

Regards

Gerry

lol…I thought it was clear…the bussbar is not a feeder and it is not a feeder tap so the conductor feeding the 30A circuit would need an OCPD ahead of the conductors. Based on the letters and chats with the NFPA they are clear that feeder taps must tap a conductor and a feeder is a conductor between the service disconnection means and the final branch circuit overcurrent device…so conductors must be protected at their ampacity…so I dont like the application…lol

Hi Paul,

thanks for that, now I get it.

Good call Jeff :smiley:

Regards

Gerry

Don’t give in so FAST my floridian friend…lol

The main thing here is where reality arrives at functionality. In reality the load is limited by the 30A OCPD that is at the disconnect and is clearly the part that Gerry was ok with and in reality it is probably ok as again the load would be limited. The functionality of the code is that I dont ( and again my opinions are mine alone, not gospel) believe the tap rules can apply here because the NEC does not provide us with tapping rules other than the ones given in 210.19 and 240.21 and these do not meet the situation.

In some cases we (today) see panels with “feed-thru” type lugs which are part of the bussbar assembly and are designed to extend the bussbar to another enclosure many times because of a need for additional circuit spaces. This issue has also been made easier now since the 42 space limitation has been lifted for the 2008 NEC on panelboards ( except for Lighting & Applicance Panelboards which remains 42 spaces, so not much of a change just cleaned it up a bit ). Anyway, these feed-thru panels are rated as such and traditionally the feed-thru conductors are sized the same as the service conductors supplying the main panel.

My personal feelings ( yes, they are mine alone ) is that approved lugs or taps on the buss of a panelboard ( manufacturer installed ) should be considered a TAP location and the rules of 240.21 should apply where applicable and give more open acceptance of this application. Why do I care if we tap a “feeder” or the “bus” in this application? Personally, I would prefer to use proper lugs and follow the tap rule versus trying to actually tap a conductor in the panelboard but thats appears to be just me with that opinion…or at least it is something I have not attempted to submit to the NFPA CMP before so who knows and I am sure brighter people than me have tried. Does the panelboard have any information about the lugs on the panel listings?

So in reality I would give POINTS to both Gerry and Jeff on this debate because I can make compelling arguements for both…BUT I have to fall on the side of “CODE” but you can be sure I will look into this more as with anything the NEC is a thick book and I might be able to pull something out of it to contradict itself. If not, what the HECK are the lugs their for…right!

Here is where it gets MUDDY…when looking at the feeder taps rules, what if we use the lugs to extend to another panel and the main panel is rated for feed-thru lugs then the tap rules would apply because the panel is designed for this application ( I dont know if the Pushamtic are to be honest with you…could be ) and as long as you had disconnection means in compliance with the tap rules it could possibly apply. Just figured I would muddy it up for you even more…lol

WAIT…WAIT…I may just flip flop on you all now that I actually went and looked at the picture…lol…lets see if 240.21 may apply.

**(1) Taps Not over 3 m (10 ft) Long. **
Where the length of

the tap conductors does not exceed 3 m (10 ft) and the tap
conductors comply with all of the following:

(1) The ampacity of the tap conductors is
a. Not less than the combined calculated loads on the
circuits supplied by the tap conductors, and
b. Not less than the rating of the device supplied by
the tap conductors or not less than the rating of the
overcurrent protective device at the termination of
the tap conductors.
A:) Lets assume it’s 10 AWG since I really can’t tell. It appears (1)is met.
(2) The tap conductors do not extend beyond the switchboard,
panelboard, disconnecting means, or control devices
they supply.
A:) It appears (2) is met.
(3) Except at the point of connection to the feeder, the tap
conductors are enclosed in a raceway, which shall extend
from the tap to the enclosure of an enclosed
switchboard, panelboard, or control devices, or to the
back of an open switchboard.
A:) Hmmm…is that off-set nipple the raceway…?..maybe so…lookout JEFF…
(4) For field installations where the tap conductors leave
the enclosure or vault in which the tap is made, the
rating of the overcurrent device on the line side of the
tap conductors shall not exceed 10 times the ampacity
of the tap conductor.
A:) 200/10= 20A, We are ok on this one.

I can see I’m going to need more Advil :(:wink:

Gerry

lol…I intentionally posted a few long winded posts here to bring Mr. pope and you around this issue because I kinda like this one. And I happen to be in a camp that believes that 240.21 needs to be re-written much clearer. If the “TAP” took place ahead of the service disconnection means then Article 240 would not even apply but from what I can gather from the image it is after the 200A main disconnect so 240 rules do apply.

The argument made to the NFPA a few times was is the “bussbar” a feeder in the purest of the sense. Let me see if I have the e-mail they send me…

So if we examine what they are saying is at the lugs the it would be a “feeder” and not a feeder tap and and tapping another conductor which is a feeder would be a “feeder tap”. Personally, I believe 240.21 rules should apply to the load side of the lugs as well if they are available but thats just me. The debate goes to is the bussbar a “feeder”, it is conductive in all cases ( obvioulsy ) and many panels are designed with Feed-Thru lugs that make it UL Listed for feed-thru connections ( which I dont think this case is mind you )…

SO what are the LUGS their for…my personal feelings is as long as the rules of 240.21(B)(1) are met I would not loose any sleep over it, it appears in THIS case the rules are met. I don’t know what the panel schedule says about those lugs and their intent so it has been a GREAT debate…I can tell you this post this on Mike Holts site and they will have no problem at all with the installation and applying 240.21(B)(1) to this application. All I am saying is I have been fighting this one for a long time and once I got an “informal” opinion from a senior electrical engineer at the NFPA I started to question the way it was written.

Is it likely to cause a fire…I dont think so.

hi Mate

that was part of my rationale, I couldn’t see any obvious dangers to either personel or equipment, normaly when we see these odd looking taps they leave down stream panels energized even when the main is thrown, that isn’t the case here.

So long as the feeder IS of the correct gauge for 30amp, thats the bit that would concern me.

It’s an interesting issue.

Regards

Gerry

Yep…see this is what forums are for…bringing out issues.

When we see a feed-thru panel, traditionally this panels additional lugs are designed to actually extend the panel to another panel and not really for applications of the “Tap” rules the way the code is written right now. Many will TWIST the code to say the bussbar is a conductor, the lugs are a conductor and then try to bring in “websters dictionary” logic into the term of conductor. The fact is the NFPA to the BEST of my knowledge consider a conductor as what it is…a conductor. IN some areas of the code we have busway applications that are being considered as conductors and they define that in their own article and sections as such and are specific to their application but unless we change the wording of the definitions of “feeders” and “feeder taps” we are bound by their application.

The principle concept of protection is that all conductors shall be protected at their ampacity ( nope, thats no cut and paste…I wrote that…) and so we so need the applications of 240.21 (A-H) in order to actually apply taps so it’s a good thing but probably way to deep for HI’s to venture into, heck it is starting to seem way to deep for ME to venture into. I am always learning and as I said I fall into the camp that believes the tap rules should apply to the lugs since the busbar is in my mind a conductor of sorts and it is on the load side of the disconnection means so if the tap rule mathmatics apply I don’t really loose sleep over it but as we see some engineers disagree and say taps must tap feeders to be feeder taps and thus feeder tap rules can only apply to feeders. How was that for a toungue twister.

Here is exactly what the NEC says and you be the judge:

**Tap Conductors. **
As used in this article, a tap conductor is

defined as a conductor, other than a service conductor, that

has overcurrent protection ahead of its point of supply that
exceeds the value permitted for similar conductors that are
protected as described elsewhere in 240.4.

**[FONT=Times New Roman][size=2]Feeder. **[/FONT][/size]

[FONT=Times New Roman][size=2]All circuit conductors between the service equipment,
the source of a separately derived system, or other

power supply source and the final branch-circuit overcurrent
device.

The I posted earlier what an “informal” Senior Electrical Engineer stated in regards to defining feeders and feeder taps…so you be the judge. What I can tell you is that many, many and many electricians and engineers differ on this one and if someone tells you that you are wrong or right…I can point you to many well known guys who disagree on this issue.

This is a GREAT subject and has spawned a few proposals of my own for the next code cycle.

Here is what the NEC gives us -
Conductor, Bare. A conductor having no covering or electrical
insulation whatsoever.

Conductor, Covered. A conductor encased within material
of composition or thickness that is not recognized by this
Code as electrical insulation.

Conductor, Insulated. A conductor encased within material
of composition and thickness that is recognized by this
Code as electrical insulation.

BUT it never actually tells us what a conductor IS in itself. Can it be a bussbar in a panelboard?. Does it mean lugs are conductors?
You tell me what YOU think it means… :slight_smile:

Here is what websters says about it…( Yes, I Cut and Pasted this from Websters Online to KEEP people happy )

Main Entry: con·duc·tor Pronunciation: \kən-ˈdək-tər\ Function: nounDate: 15th century**:** one that conducts: as a**:** guide](http://www.merriam-webster.com/dictionary/guide) b**:** a collector of fares in a public conveyance c**:** the leader of a musical ensemble d (1): a material or object that permits an electric current to flow easily — compare insulator](http://www.merriam-webster.com/dictionary/insulator), semiconductor](http://www.merriam-webster.com/dictionary/semiconductor) (2): a material capable of transmitting another form of energy (as heat or sound)

So since the NEC style manual says websters can be used…and since the NEC uses the term alot I would think it would define it within it’s own scope and maybe propose this new definition to the NEC.

Conductor.Bare,Covered or Insulated-a material or object that permits an electric current to flow easily as it applies to the application of an electrical installation.
[/FONT][/size]

What do ya think…should I submit it or do ya think it is needed?

UNCLE - I give!

Do you have anything stronger than Advil Gerry?

Ask him if he has any Diprivan, an anesthetic widely used in operating rooms to induce unconsciousness and I hear it is quite powerful. But it is only advised to be used in the presence of a famous doctor.

I switched to Scotch hours ago Jeff :wink:

Hic

Gerry