ECN Electrical Forum
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HI . I NEED TO MAKE SOME LOAD CALCULATIONS FOR A NEW DENTAL OFFICE WITH A THREE PHASES MAIN PANEL, 100 AMPS AND I HAVE EQUIPMENT OF 120 VOLTS; 208 AND 208 THREE PHASES, BUT WHEN I TRY TO DO THE CALCULATION I JUST CHECK DIFFERENT BOOKS AND ALL OF THEM HAD DIFFERENT WAYS TO DO AND I GOT CRAZY, I JUST MADE MY OWN SYSTEM AND LOOKS FINE BUT I DONT KNOW IF IT IS CORRECT, I JUST SUM THE WHOLE POWERS AND AFTER 10000 VA I JUST PUT THE REST WITH 0.5 OF FACTOR TO LOWER MY AMPS.
CAN SOMEBODY TELL ME WHERE I CAN FIND REALLY EASY TO UNDERSTAND EXAMPLES BOOK OR CASES BUT REALLY CLEAR TO FOLLOW???
THE BOOKS I HAVE THEY REALLY SAY DIFFERENT METHODS ESPECIALLY WITH THE NEUTRAL WIRE SIZE AND AMPS OF THE SYSTEM .
THANKS
LUIS

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[This message has been edited by Webmaster (edited 09-20-2004).]

Article 220, 2002 NEC.

Annex D examples in the back of NEC.

Irsilvas,
Stallcups Master Electrician's Study Guide, and Stallcups Electrical Design book has good examples to guide & practice with. I have used it myself to prepare for my Master's exam and in my EE Practice. You also need to refer to the appropriate NEC articles for health care facilites.