Missing High-Leg???

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davedottcom

davedottcom

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Can someone tell me if this panel was built this way by the manufacturer or if it was altered? I've never seen this before.

1970's? G.E. 300 Amp 3-Phase Panel 240/120 w/ a 208 high leg

The first 3 rows of bolt-on style phase bars are normal Phase-A Phase-B Phase-C, but then it changes for the rest of the spaces. The 208V B-Phase is missing! It goes ACACACAC for the rest of the spaces.
 
I'm not sure if they made them out of the box that way, but there were (and I think still are) some that you could rearrange the bus fingers to do that if you wanted to. I was in a GE panel not too long ago that still had a manila envelope in the bottom full of various fingers and instructions printed on the envelope.
 
Marc, I never knew that was possible or exceptable.

My real concern is this: I'm back feeding this panel with a 26,000 Solar PV system and I'm not sure what effect , if any, this "Unbalanced load" will have on the system. The panel is full of 240V Ac Units, and no 120V circuits... which makes me wonder why they even did this in the first place.
Since any unused power from the PV is backfed to the utility, I picture almost 1/3 of the PV power going back to the utility on just the B-Phase instead of being utilized by equipment.

Any thoughts?
 
I have seen a lot of stock panels similar to that. Sometimes they only have one space for the high leg for an AC. They considered it a better use of space in the panel
 
Some manufacturers "factory assemble" their 240/120 3PH 4W panels this way when you order 1-pole spaces instead of 3-pole spaces.
 
I wonder if the parts "fingers" are still available to convert it back to a regular 3-phase pattern?

Now that I know the panel is legit, I'm just concerned with the PV system. I landed the back feed beaker on the available A,B&C but I'm really curious if the load on A&C will effect the effeciency of the PV system.

Thanks for the replys guys!
 
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