apartment wiring loads

Reply

  #1  
Old 11-27-07, 05:43 PM
N
Member
Thread Starter
Join Date: Nov 2007
Posts: 13
Received 0 Votes on 0 Posts
apartment wiring loads

so i'm going to wire my basement for a guest unit... do these calculations make sense while i'm trying to figure out how big a subpanel needs to be?

lighting: 3A (14 23W CFL lighting fixtures)
Heat: 16A (3800W of 240V electric baseboard)
Kitchenette: 45.5A (10A micro, 12.5A toaster, 15A burner, 8A fridge)
misc: 4A (computer, clock, tv)

so i figure if someone's down there with their computer on, listening to the TV, with all the lights on, and is cooking up a storm with all their appliances, they'll be using 70A. so how big should the feeder breaker be going to the basement subpanel?

thanks
 
Sponsored Links
  #2  
Old 11-27-07, 05:52 PM
R
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,970
Received 0 Votes on 0 Posts
Well, your calculation is off. You cannot add amps at 240 volts to amps at 120 volts. You need to convert them all to the same voltage.

The breaker should be sized for the panel and the wire. You most certainly want a 100 amp panel, so that means you can use any size breaker up to and including 100 amps at the main panel, as long as the wire is sized large enough. I would probably go with a 60 amp breaker.
 
  #3  
Old 11-27-07, 06:08 PM
N
Member
Thread Starter
Join Date: Nov 2007
Posts: 13
Received 0 Votes on 0 Posts
So if I convert my 240v heating system to a 120v amp rating I'd add another 16A to my load so I'd have 85A or something. Why would a 60A breaker be sufficient?
 
  #4  
Old 11-27-07, 06:50 PM
R
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,970
Received 0 Votes on 0 Posts
First, nobody runs everything at the same time.

Second, the feeder to the sub panel will be a 240 volt breaker.
 
  #5  
Old 11-27-07, 08:21 PM
J
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
Received 0 Votes on 0 Posts
Third, you want to stay with 240-volt heat.

60 amps is plenty (even if everything is running at the same time).
 
Reply
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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: