Range calculation: N.E.C 220.55?? - Electrician Talk - Professional Electrical Contractors Forum
 Electrician Talk - Professional Electrical Contractors Forum Range calculation: N.E.C 220.55??
 Register Articles Rewards Search Today's Posts Mark Forums Read

 09-04-2012, 11:15 PM #1 Member     Join Date: Jul 2012 Location: Florida Posts: 60 Rewards Points: 75 Range calculation: N.E.C 220.55?? I'm studying to get my license and need help with one of my test questions/answers . One cooktop and two ovens are connected to one branch circuit in a kitchen of a one family dwelling. The cooktop has a nameplate rating of 4kw at 240v, while each oven has a nameplate rating of 5.5kw at 240v. The minimum load calculation for this branch circuit is ______ watts. I don't understand how they made this equation. I appreciate the help. Chas3x
 Join the #1 Electrician Forum Today - It's Totally Free! ElectricianTalk.com - Are you a Professional Electrical Contractor? If so we invite you to join our community and see what it has to offer. Our site is specifically designed for you and it's the leading place for electricians to meet online. No homeowners asking DIY questions. Just fellow tradesmen who enjoy talking about their business, their trade, and anything else that comes up. No matter what your specialty is you'll find that ElectricianTalk.com is a great community to join. Best of all it's totally free!

 Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ElectricianTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

09-05-2012, 12:29 AM   #2
Senior Member

Join Date: Nov 2010
Location: US
Posts: 3,720
Rewards Points: 132

Quote:
 Originally Posted by Chas3x I'm studying to get my license and need help with one of my test questions/answers . One cooktop and two ovens are connected to one branch circuit in a kitchen of a one family dwelling. The cooktop has a nameplate rating of 4kw at 240v, while each oven has a nameplate rating of 5.5kw at 240v. The minimum load calculation for this branch circuit is ______ watts. Attachment 16469 I don't understand how they made this equation. I appreciate the help. Chas3x

Look at note 4 of Table 220.55. That is for branch circuit load.

Edit: I just saw the answer sheet said to reference note 4. Do you understand how to use the table, and how to apply note 4?

Last edited by A Little Short; 09-05-2012 at 12:31 AM.

 The Following User Says Thank You to A Little Short For This Useful Post: Chas3x (09-05-2012)
 09-05-2012, 01:48 AM #3 NJ-IEC     Join Date: Jan 2007 Location: New Jersey Posts: 14,376 Rewards Points: 424 Haven't done one of these in awhile... 3 appliances become (1) appliance. Column C (1) appliance is 8,000 watts. 4kw + 5.5kw + 5.5 kw is 15kw. 15kw-8kw = 7kw Add 5% for each additional kw over 8kw. 8kw x 35% = 10,800 watts 10.8 kw/ 240 = 45 amps. That's off the top of my ahead I could be wrong. __________________ Replies based on NEC 2014
 The Following User Says Thank You to Magnettica For This Useful Post: Chas3x (09-05-2012)
 09-05-2012, 06:31 AM #4 felonious smile.     Join Date: Mar 2010 Location: Long Island,NY & Poconos Posts: 15,891 Rewards Points: 572 When is it legal to run a full size range on #10s ? My last full time gig pulling wires at a Marriot residence inn had me doing that. __________________ Clean this mess up before we all end up in jail, the test tubes and the scale. Just get it all out of here. Is there gas in the car?
09-05-2012, 08:36 AM   #5
Senior Member

Join Date: Nov 2010
Location: US
Posts: 3,720
Rewards Points: 132

Quote:
 Originally Posted by Magnettica Haven't done one of these in awhile... 3 appliances become (1) appliance. Column C (1) appliance is 8,000 watts. 4kw + 5.5kw + 5.5 kw is 15kw. 15kw-8kw = 7kw Add 5% for each additional kw over 8kw. 8kw x 35% = 10,800 watts 10.8 kw/ 240 = 45 amps. That's off the top of my ahead I could be wrong.
Wrong!
15kw-12kw= 3k
5% for each kw over 12kw
5% x 3kw=15%
8kw x 15%=1.2kw or 1200 w
8kw + 1.2kw = 9.2kw
or as the test wanted =9200W

 The Following 4 Users Say Thank You to A Little Short For This Useful Post: Chas3x (09-05-2012), I_get_shocked (09-05-2012), Magnettica (09-05-2012), mrxman (09-06-2012)
 09-05-2012, 02:13 PM #6 Member     Join Date: Jul 2012 Location: Florida Posts: 60 Rewards Points: 75 So you reduce the 15kw by the highest kw (12) in column C?
 09-05-2012, 02:21 PM #7 Member     Join Date: Jul 2012 Location: Florida Posts: 60 Rewards Points: 75 I just figured it out! I appreciate your help.
09-05-2012, 07:24 PM   #8
NJ-IEC

Join Date: Jan 2007
Location: New Jersey
Posts: 14,376
Rewards Points: 424

Quote:
 Originally Posted by Little-Lectric Wrong! 15kw-12kw= 3k 5% for each kw over 12kw 5% x 3kw=15% 8kw x 15%=1.2kw or 1200 w 8kw + 1.2kw = 9.2kw or as the test wanted =9200W
It's been awhile. I knew this like the back of my hand for the exam, but now not so much. I would have to check my Tom Henry books if I ever ran into this in the real world.

Thank you for correcting me.
__________________
Replies based on NEC 2014

09-05-2012, 07:28 PM   #9
NJ-IEC

Join Date: Jan 2007
Location: New Jersey
Posts: 14,376
Rewards Points: 424

I don't like to make excuses for anything, but it was late and I had woken up from sleeping. I see now where I went wrong.

Quote:
 Notes: 1. Over 12 kW through 27 kW ranges all of same rating. For ranges individually rated more than 12 kW but not more than 27 kW, the maximum demand in Column C shall be increased 5 percent for each additional kilowatt of rating or major fraction thereof by which the rating of individual ranges exceeds 12 kW.
__________________
Replies based on NEC 2014

 The Following User Says Thank You to Magnettica For This Useful Post: Celtic (09-05-2012)
09-05-2012, 11:10 PM   #10
Senior Member

Join Date: Nov 2010
Location: US
Posts: 3,720
Rewards Points: 132

Quote:
 Originally Posted by Magnettica It's been awhile. I knew this like the back of my hand for the exam, but now not so much. I would have to check my Tom Henry books if I ever ran into this in the real world. Thank you for correcting me.
No problem, it was fun! I'm usually the one getting corrected!

 The Following User Says Thank You to A Little Short For This Useful Post: Magnettica (09-06-2012)
09-06-2012, 12:49 AM   #11
Junior Member

Join Date: Sep 2012
Location: MN
Posts: 1
Rewards Points: 10

Quote:
 Originally Posted by Little-Lectric Wrong! 15kw-12kw= 3k 5% for each kw over 12kw 5% x 3kw=15% 8kw x 15%=1.2kw or 1200 w 8kw + 1.2kw = 9.2kw or as the test wanted =9200W
Thanks for the info.

 09-07-2012, 08:42 AM #12 Member   Join Date: Mar 2011 Location: ny Posts: 55 Rewards Points: 25 [quote=Little-Lectric;801021 15kw-12kw= 3k 5% for each kw over 12kw 5% x 3kw=15% 8kw x 15%=1.2kw or 1200 w 8kw + 1.2kw = 9.2kw or as the test wanted =9200W[/quote] haha thats the way i learned it !!!!

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are Off Pingbacks are Off Refbacks are Off Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post BIGRED General Electrical Discussion 30 07-11-2010 01:15 AM Conduit Phil General Electrical Discussion 24 06-20-2010 09:18 AM charlie Bob General Electrical Discussion 67 03-20-2010 10:43 PM azsparky General Electrical Discussion 2 12-05-2008 09:40 PM jelectric NEC Code Forum 3 03-09-2007 10:54 PM

All times are GMT -4. The time now is 12:42 PM.