As a follow up to the Duct calculations post a couple weeks ago, we are now asking for some feedback on some of the electrical calculations that we do in Revit MEP.
Attached is a draft PDF version of some information on how we do these calculations. We would appreciate any information that you can provide on what information in the attached document is helpful as well as any information that you think might be missing.
You can download the file at: Download Revit_MEP_electrical_calculations
thanks!
jason
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There seem to be two typos on page 2. In paragraph 2, "300MCM" should be "#8". In paragraph 6, "#3" should be "#4" and the area should be changed to match. I havent had time to make it through more of the document.
Posted by: David Rushforth | August 19, 2009 at 10:31 AM
Yea, there is quite a difference in #8 and 300MCM. Nice catch in paragraph 6 as well. I'll be sure and let the team know about these.
Thanks David!
jason
Posted by: jason | August 19, 2009 at 02:45 PM
Alright, I made it through the next page and there seems to be a typo in paragraph 8. The wrong area is used in the calc giving the wrong result of a #4 neutral (it should be much larger). This error shows in the final wire size at the bottom of the example as well.
Posted by: David Rushforth | August 20, 2009 at 07:22 PM
I have sent this to my electrical engineers for review.
Posted by: John Cook | August 21, 2009 at 11:14 AM
If you did not upsize your conductors for voltage drop the conductors would be undersized. You only use the 90c value for derating.You must size based on the lowest terminal rating, which for now is 75c or less.
Posted by: Jeff H. | September 19, 2009 at 03:27 AM