HVAC breaker terminals

I'm not going to put wire nuts in a new service install (since I have a humongous J box 23" underneath it that is) but what would be the acceptable length to transition from a lug requiring a larger gauge to a smaller, yet current acceptable, gauge? Because, like Eddie702 said, now that I know I'm going to be looking for it everywher$.
 
You only need the minimum length required to make your splice and fit into the terminal.
Not wanting to be the source of discussion at the bar, I would probably say to leave at least a couple of inches but less than 1 foot, when everything is in one box. Just don't put it in front of the neutral or ground bars.
 
The majority of condensing units that I have installed are close to the home service. I have never reduced the wire size, only increased the wire size for longer runs. The increased cost is pennies on the dollar.
 
Went back today, spliced in panel 😔 so that I'm not misleading anyone in the future (passed inspection last week), and was surprised at how easy the terminals were to loosen. Previously torqued to 45 in. lb. so it should have put up a tiny bit more resistance, maybe that's saying something(?) but 45 in.lb. shouldn't care if wire is inserted or not.
Below are photos of a brand new HOM 50's terminals. You can kinda see how some 10 stranded might not benefit from full compression as it spreads out - but the terminal on the right is only snugged.

HOM 50 lugs.jpg
 
TwistLock said:
Homeline
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Not surprised this is why I never use Homeline panels, they have weird quirks, they are not really interchangeable like Murry / ITE-Siemens / Eaton BR. The busbar seems flimsy always aluminum I think.
Now QO thats a great panel, I have cleaned up QO panels that are over 50 years old, solid copper busbars.
 
pipe_bender said:
Not surprised this is why I never use Homeline panels, they have weird quirks, they are not really interchangeable like Murry / ITE-Siemens / Eaton BR. The busbar seems flimsy always aluminum I think.
Now QO thats a great panel, I have cleaned up QO panels that are over 50 years old, solid copper busbars.
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Can confirm HOM busbars flimsy. When I first opened box, third from bottom tandem stab was bent to 45º (from factory). Covered it in cardboard and bent it back to perpendicular... it was as soft as butter to bend back & surprised me. (no cracks etc visible)
 
jim dungar said:
For those who really want to know. A data sheet from 1967, shows 30 & 40A QO had lugs for #8-#4 AWG Cu.
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I went out to shop and looked at some breakers I have. Had a 40 amp that probably from sometime in 1990's based on some minor details on how logo was applied and/or whether amp rating was molded or printed on it. It says #8 - #2. I can't believe I never noticed this until this thread brought it to my attention.

Now the thing that really makes a lot of sense, I had a 125 amp breaker maybe between 10 and 15 years old and the lug rating is 12 AWG to 2/0 AWG. :unsure:
 
pipe_bender said:
Not surprised this is why I never use Homeline panels, they have weird quirks, they are not really interchangeable like Murry / ITE-Siemens / Eaton BR. The busbar seems flimsy always aluminum I think.
Now QO thats a great panel, I have cleaned up QO panels that are over 50 years old, solid copper busbars.
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The Homline bus is tin plated aluminum. AFAIK has always been on every Homeline product. But this was originally made to be a competitive product to use instead of Murray/ITE/Siemens, BR, GE in particular. Homeline breakers are fully interchangeable (other than the listing) with Murray ITE Siemens BR GE and most others of similar bus connect design. Homeline panel bus however has a little extra bump on the bus that prevents those other breakers from plugging all the way on. In my experiences they will plug on and will function but it does give you more trouble putting the cover on than if it were an actual Homeline breaker.

QO bus back in late 60's/ early 70's was aluminum bus in many 125 amp or less versions and those were known to fail at breaker connections. Most popular one of those was the ones with the 100 amp main breaker that took up the full width of the breaker mounting space.

Otherwise they are tin plated copper with the exception of those 6 and 8 space versions with the horizontal bus. They have tin plated in both copper and aluminum for those. Aluminum is most commonly found version though, and likely all you will find at a big box store.
 
TwistLock said:
Can confirm HOM busbars flimsy. When I first opened box, third from bottom tandem stab was bent to 45º (from factory). Covered it in cardboard and bent it back to perpendicular... it was as soft as butter to bend back & surprised me. (no cracks etc visible)
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I mixed my reply to you into what I said in post 29. was intending to quote you in there as well.
 
I wouldn't have given Homline a second thought, associating it with a box store, but a local quality distributor stocks it and also priced it $60 less than the box store so I bit thinking 'give it a shot'. Well I learned a lot (as well as from your info). I'm sure it will perform fine, 225 rated buss, and I liked the layout & space, but there's a lot of gotcha's.
The only reason I noticed the lug rating myself was the printing. Normally it's raised/embossed text that blends. Later when I examined some 40's / 50's they were embossed too and though all were purchased from same supplier they couldn't find any more printed ones.

printed vs embossed.jpg
 
TwistLock said:
I wouldn't have given Homline a second thought, associating it with a box store, but a local quality distributor stocks it and also priced it $60 less than the box store so I bit thinking 'give it a shot'. Well I learned a lot (as well as from your info). I'm sure it will perform fine, 225 rated buss, and I liked the layout & space, but there's a lot of gotcha's.
The only reason I noticed the lug rating myself was the printing. Normally it's raised/embossed text that blends. Later when I examined some 40's / 50's they were embossed too and though all were purchased from same supplier they couldn't find any more printed ones.

View attachment 2579467
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Result of value engineering. The printing requires an extra step in the manufacturing process.
 
retirede said:
Result of value engineering. The printing requires an extra step in the manufacturing process.
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But the molding requires more part numbers (different breaker sides for each lug size) and more inventory control. Printing requires only 1 blank breaker side, regardless of lug size.
 
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retirede said:
IMO, eliminations of an entire process step is still a net cost savings.
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It is a process to manufacture and store blanks with different embossments, it is less of a process to manufacturer a blank side and imprint as necessary. The simplicity of printing is also one reason it is used by counterfeiters.
 
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