timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
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YesThing is, can you still get split bus panels?
They continue to be available. But now for this purpose, instead of saving money on the main breaker costs.
YesThing is, can you still get split bus panels?
No, it's not.Another question is whether splitting the bus is considered a valid field modification.
Do not do that.
You don't want to remove the N/G bond.This is presuming that there are no convertible split panels (IE either come as subpanel or have removable N-G bond). If there are, then maybe doing funky stuff with split subpanels is going to be the new DIY solar meme.
Actually, most interlocks are between the main and a backfeed breaker.You have the interlock on a forward feeding breaker on the top bus and a backfeed breaker on the bottom, which is confusing (and makes it harder to understand IMO) because usually interlocks are on two backfeed breakers.
Do you mean NQ or from other manufacturers?Plenty of options outside of Homeline style though.
QO should be available split-bus, NQ for sure. Equivalents with other manufacturers as well. Homeline is pared back AFAIK.Do you mean NQ or from other manufacturers?
Oh ok. All my panels at home have backfed mains.Actually, most interlocks are between the main and a backfeed breaker.
I was presuming use in the most likely situation for me.You don't want to remove the N/G bond.
This is still the enclosure with the first means of disconnect.
Secondary sources should be unbonded, up to this point.
A typical common neutral setup.
It’s not clear that the first one was unmodified either. You would need to specifically find a split bus that skips two positions on the jumper to the second bus. Look at the home line split bus listed above, it doesn’t skip. Now assuming that split bus has a breaker feeding second bus, and there is a left to right interlock, then the inverter backfeed can be put to the left. With no modificationDo not do that.
It leaves the sub bus feeders unprotected.
And the modification breaks the UL listing.
Not sure what you mean by skip.You would need to specifically find a split bus that skips two positions on the jumper to the second bus. Look at the home line split bus listed above, it doesn’t skip.
Not left to right.and there is a left to right interlock,
There shouldn't be any modifications done.The modification seems to be in an ambiguous area since the connection between buses is done with standard components from factory anyway / whether the individual buses inside are listed appropriately.
The Homeline picture hasNot sure what you mean by skip.
It is a split-phase bus, being fed by a 2 pole breaker.
In the OP it is up to down interlockNot left to right.
Up and down.
The homeline panel posted above would also be up and down interlock.In the OP it is up to down interlock
That will not work with the homeline panel as OP drew it.
It is probably possible to do either left right or top bottom interlock but not how OP drew it. Because OP inserts a inverter backfeed in between the jumper between top and bottom buses
It’s way clearer if I draw it but I will only put the time into drawing if someone makes a strong case the time I put in is worth it to them.
I don’t think trying to reach consensus via text is efficient but I also don’t know that anyone really cares or benefits. (I’m satisfied with my learning and understanding of the situation)
Yes this is what I had in mind.The homeline panel posted above would also be up and down interlock.
The backfeed breaker would be installed below the lower section existing feeding breaker.
How does the 3 phase panel work? 120V critical loads panel? Does it end up being confusing or space inefficient to work around the stab arrangement?I actually got as far a disassembling a QO panel and marking the busbar where I would cut it.
I also thought about 3-phase panel, with one branch for backed up loads.
I'm using multiple breaker panels for heavy loads on grid, critical loads + AC coupled PV, important backed up loads. And I use a main breaker only panel for load-side tap (no 120% rule.
You can get PV ready panels with line side tap and second main breaker.