Hi. As part of my ongoing effort to rough out the electrical system at our space, I have recreated a panel schedule spreadsheet I saw in an older post.
Seems to work fine for 240 volt 1ph (2p) and 3ph (3p) loads.
Now I'm trying to figure out how to calculate a combination of 120v 1ph (L-N) loads and 208 3ph loads (L-L-L) and 208 1ph loads (L-L) and make the spreadsheet work.
What is throwing me a bit is with the 2 & 3 phase loads, I have divided the total load (circuit amps * voltage) by the number of poles to help balance the load on the panel.
example: 60A 3ph load = 60*208 = 12,480 VA divided by 3ph = 4160 per phase
Later, I add up all VA on each phase, and divide by 208x1.73 to get the total ampere load. (ignoring continuous calcs and reductions)
Now, when I start to add 120v loads, do I just put the entire load on the single phase for that circuit?
example: 15a 1ph load at 120v = 1800va = load on that phase?
If so, can I go ahead and just add up all the loads on each phase of my chart and divide by 208x1.73, or do I have to keep track of 208v and 120v loads separately, then divide by the 120v or 208x1.73 value?
I have attached a pdf file of what my panel schedule chart looks like, with some sample loads. I think the 208 1ph and 3ph loads calculate correctly.
I am not sure about the 120v loads... If they need to be tabulated separately, I have to figure out a way to automate that in the spreadsheet...
I'd be happy to share this spreadsheet with anyone that wants a copy once we get it to work correctly!
Thanks,
Bryan
Seems to work fine for 240 volt 1ph (2p) and 3ph (3p) loads.
Now I'm trying to figure out how to calculate a combination of 120v 1ph (L-N) loads and 208 3ph loads (L-L-L) and 208 1ph loads (L-L) and make the spreadsheet work.
What is throwing me a bit is with the 2 & 3 phase loads, I have divided the total load (circuit amps * voltage) by the number of poles to help balance the load on the panel.
example: 60A 3ph load = 60*208 = 12,480 VA divided by 3ph = 4160 per phase
Later, I add up all VA on each phase, and divide by 208x1.73 to get the total ampere load. (ignoring continuous calcs and reductions)
Now, when I start to add 120v loads, do I just put the entire load on the single phase for that circuit?
example: 15a 1ph load at 120v = 1800va = load on that phase?
If so, can I go ahead and just add up all the loads on each phase of my chart and divide by 208x1.73, or do I have to keep track of 208v and 120v loads separately, then divide by the 120v or 208x1.73 value?
I have attached a pdf file of what my panel schedule chart looks like, with some sample loads. I think the 208 1ph and 3ph loads calculate correctly.
I am not sure about the 120v loads... If they need to be tabulated separately, I have to figure out a way to automate that in the spreadsheet...
I'd be happy to share this spreadsheet with anyone that wants a copy once we get it to work correctly!
Thanks,
Bryan