Need help w/ figuring Existing load calculation based off of 220.87

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CustomElectricLLC

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Midlothian Texas
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Electrical Contractor
Installed a 200A breaker into an existing 800A service but now city is having me prove to them that there’s enough headroom available in the service for that load. So I’m trying to figure out how to get my max demand so I can install addition loads into existing service by using 220.87. Is the attached info from utility enough for me to run the calculation? I know that I’m missing the pF and I’ve read through some other threads on here about this. I think that it shows peak demand in a day so that’s what I’d be going off of correct? I’m having trouble figuring out how to convert the numbers to figure out max demand etc. I know that kwh/ pf = kw but I don’t have power factor. Even if assume .80 I think it looks like there is enough room... please advise.
32cfa26515093f8ac1fc8c290732051f.jpg



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Strathead said:
Unless I am mistaken the KW column IS the peak demand for the given month. So line 7 is the highest recorded month and should be fully capable of being used to run the calculations.
Click to expand...

So I would divide that by the days in the month of that line then do the calc with that number? I’ve been trying to wrap my head around this but hasn’t been easy!


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What I don't understand is the difference between the "KW" column and the "KW Usage" column. The number you are seeking is the single highest KW reading for any month within a one year time span.

By the way, what is the supply voltage?
 
Strathead said:
So line 7 is the highest recorded month and should be fully capable of being used to run the calculations.
Click to expand...
I don't follow you here. The 7th row in the table (which also applies to July - the 7th month) does not have the highest KW value or the highest KW Usage value.

 
dvpvic said:
So I would divide that by the days in the month of that line then do the calc with that number? I’ve been trying to wrap my head around this but hasn’t been easy!


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Click to expand...

9/26 is the highest, I looked wrong. The amount is 1240 KW and that is peak, so you divide 1240 by 240 volts and you have your peak load amperage.
 
dvpvic said:
So I would divide that by the days in the month of that line then do the calc with that number? I’ve been trying to wrap my head around this but hasn’t been easy!


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Click to expand...
Demand is essentially an instantaneous number so you would never divide by a unit of time to arrive at the demand number. I say essentially because utilities normally show the peak demand over a short time period, often 15 minutes.
 
Strathead said:
9/26 is the highest, I looked wrong. The amount is 1240 KW and that is peak, so you divide 1240 by 240 volts and you have your peak load amperage.
Click to expand...

1240KW / 240V = 5,166 A
1240KW / 360V = 3,444 A
1240KW / 831 = 1,492 A

So, I don't think that column (the one with 1240KW) means what I think you are looking for.

What does that column mean? It can't be maximum demand because it's only an 800A service (BTW, what is the phase/voltage?).
 
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