Panel Scheduleing/Load Calculations

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Deadfrog

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Ontario Canada
Hi guys. I was hoping for a bit of help and direction if someone is so kind. A little background of my situation and what I am trying to do.

I am working as an Engineer in Training for a small engineering firm. I have an been asked to do a load calculation for an industrial building. The problem is that I have never done one before. I am very new out of school with an electrical background however my employer is mechanical and school didn't teach me much of anything besides calculus... well nothing really practical at least. Once I have completed the calculations I am to meet with his partner out of town and he is going to show how to do the rest of the project. But for this part I am sorta on my own (unless maybe some forum help :) )

I have searched the web for some examples that would help me in my situation but I have found little to help.

So far I have drafted up the location of receptacles, pumps, etc and read over the code for Circuit Loading and Demand Factors several times. But it leaves me with so many voids on what I should do or even how I should approach this.

Any advice for a noob? Anyone got examples or templates they wouldn't mind sharing? :grin:

All my work will be checked over eventually and normally I can find enough information on google to figure anything out.. but I have spent all day searching and I am having no luck. Very very frusterated at this point


The building is roughly 65000 sq ft floor space. Im going to list some equipment if you want more of an idea of what I am putting in.

Item Quantity
External receptacles (wp gfci) 18
general receptacles - shop 74
general receptacles - office 119
general receptacles - 2nd floor 88
Block heater receptacles 20
Refrigerator 2
Microwave 2
Range 1

Nederman exaust fans 3
Alt. Bench 1
Parts Washer 1
Hose Crimp 1
Battery Charger 1
Pressure Washer 1
Jockey Pump 1
Sprinkler Pump 1
RTU 1
Compressor 1
Welding Receptacles 7
OH (door controls) 120v 12
Large OH (240v) 1
Sign 1

Should I treat singe phase and 3 phase seperately?


I would be more then happy to provide more information if needed. Any and all help is appreciated. Sorry for the long read.
 
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Dont worry about anything and this forum can help you in any part of electrical.
I have uploaded for you some excel sheet and calculation method and also panel schedule design. It will help you in your work and if you have any farther question please let us to know.
Please click below link

Load calculation
 
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Don't know if this will help. Sometimes when I want to see how others would format a design, or show a code compliance, I look to see how others do it, not being a real Engineer. This is a link to Ridgeways Reprographics in Houston open plan room. You should be able to find something similar and figure it out, if noone else comes up with a short cut to learning.

https://order.e-arc.com/arcEOC/PWELL_PublicList.asp
 
Should I treat singe phase and 3 phase seperately?
No. At the load calculation phase of a project, everything is done in terms of three phase loads. For example, single phase, 120 volt, receptacle loads will be powered from three phase panels.


Please note that all loads should be expressed in terms of VA, and not in terms of current. You cannot add amps to amps, and expect to get amps as a result. That is because the amps on Phase A are 120 degrees out of phase from the amps on Phase B, and the actual "addition" (per Kirchhoff's Current Law) would have to be done with phasors, or worse with trigonometry. But you can add VA to VA and get VA, because it is a directionless (scalor) quantity.

Welcome to the forum.
 
What what is the voltage and number of wires from the source or supply? Does this building contain an office space?
 
Thanks for the help guys,

xformer, Yes the building does have office space, 36400 sq ft, the shop is the other 33600 sq ft. Not sure yet what the supply will be, but it will all be 600v, 240v, or 120v.


Ham, the file you uploaded for me has already exceeded it's max downloads. I appreciate the effort though. Re upload?

Thanks for the info Charlie, and I do feel welcomed :)

shamsdebout, thanks I saw that page too, wasn't too clear on what to actually do though for the load calculations.
 
... I have an been asked to do a load calculation for an industrial building. The problem is that I have never done one before. ...

...

... But it leaves me with so many voids on what I should do or even how I should approach this.

...
Have you looked over (studied) the load calculation examples in Annex D of the Code?
 
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