Microwave on overhead lights (15A) circuit?

Reply

  #1  
Old 05-11-04, 07:13 PM
Zathrus
Visiting Guest
Posts: n/a
Question Microwave on overhead lights (15A) circuit?

About to begin a kitchen remodel, part of which is installing an over-the-range microwave in place of the existing vent hood. Currently the microwave shares a 20A circuit with the refrigerator and nothing else. The current vent fan is on a 15A circuit that is shared with some overhead lights (2 in kitchen, 1 in dining area, 2 outdoor).

Is it ok to rewire the vent fan area so the microwave can be plugged into this existing circuit, or do I need to run an extension from the existing 20A circuit (which would then have 3 outlets on it -- the refrigerator, the former microwave location, and the new OTR location)? FWIW, the microwave is 1100W plus the fan (?W) and lights (60W total).
 
Sponsored Links
  #2  
Old 05-11-04, 08:25 PM
jillofalltrades
Visiting Guest
Posts: n/a
I am dealing with similar circumstances myself, and just learned today that our local codes require the microwave to run on its own circuit. It may be different where you are, of course, but that's code out here..
 
  #3  
Old 05-12-04, 08:04 PM
ampz's Avatar
Member
Join Date: Feb 2004
Location: Philadelphia
Posts: 536
As Jill stated the micro should be on a dedicated circuit {15a is fine}.The NEC requires large appliances {fridge,micro,dishwasher,etc} to be on seaparate circuits.You have the potential to overload both the 15a or the 20a circuit if the micro is connected to either of them.I would run a dedicated line.
 
  #4  
Old 05-12-04, 10:48 PM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
Although an excellent idea to do so, the NEC does not require any of those things (fridge, micro, dishwasher, etc.) to be on a separate circuit.
 
  #5  
Old 05-13-04, 11:40 AM
Member
Join Date: Apr 2003
Location: Eastern PA
Posts: 354
code

The NEC does have some pretty stringent requirments for Kitchen electrical so make sure you review them. Now is the time to make sure you are up to code.
You'll want to have it all inspected as well. If for no other reason than you home owners insurance. They tend to frown on fires caused by homeowner work.
1100 watts is a pretty good draw. I definately would NOT put this on any lighting ciruit. There is too much probability that at some point you will be standing in the kitchen in the dark with no way to find your popcorn. Personally I would run a single 15 amp circuit for it. In my own house I ran a 14/2 for the fridge but I've got it on a 10 amp breaker. I did this for a few circuits in the house. If there is no way the circuit is going to need more than 10 amps in normal use you may save the equipment from more damage if the breaker kicks that much sooner, or save yourself a fire.
 
  #6  
Old 05-13-04, 12:26 PM
hornetd's Avatar
Member
Join Date: Aug 2001
Location: Maryland
Posts: 695
Exclamation Equipment Fastened in place

Originally Posted by John Nelson
Although an excellent idea to do so, the NEC does not require any of those things (fridge, micro, dishwasher, etc.) to be on a separate circuit.
John
This particular microwave would be "equipment fastened in place." For that reason section 210.23 Permissible Loads would apply.
210.23 Permissible Loads.
In no case shall the load exceed the branch-circuit ampere rating. An individual branch circuit shall be permitted to supply any load for which it is rated. A branch circuit supplying two or more outlets or receptacles shall supply only the loads specified according to its size as specified in 210.23(A) through (D) and as summarized in 210.24 and Table 210.24.
(A) 15- and 20-Ampere Branch Circuits. A 15- or 20-ampere branch circuit shall be permitted to supply lighting units or other utilization equipment, or a combination of both, and shall comply with 210.23(A)(1) and (A)(2).
Exception: The small appliance branch circuits, laundry branch circuits, and bathroom branch circuits required in a dwelling unit(s) by 210.11(C)(1), (2), and (3) shall supply only the receptacle outlets specified in that section.
(2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires (lighting fixtures), shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord-and-plug-connected utilization equipment not fastened in place, or both, are also supplied.
The way I read that section you cannot put the microwave on the fifteen ampere lighting circuit unless it draws less than 7.5 amperes. Since the microwave in question is rated at 1100 watts it would draw about 9.2 amperes. That doesn't mean that the code requires a dedicated circuit for the microwave but in this case it is a difference that makes no difference.
--
Tom Horne
 

Last edited by hornetd; 05-13-04 at 12:31 PM. Reason: Edited for clarity
  #7  
Old 05-14-04, 11:38 AM
Zathrus
Visiting Guest
Posts: n/a
Originally Posted by speedy72
The NEC does have some pretty stringent requirments for Kitchen electrical so make sure you review them. Now is the time to make sure you are up to code.
For reference, my city is under 1996 NEC. The house was built in 1982. I know I don't have to bring the entire kitchen up to current code, which is good since that would be pretty much impossible. I've brought the house as a whole much closer to current code than it was when I bought it 5 years ago though. This will just be another step I guess.

That said, I'll just run a 20A circuit to the location. It'll actually be easier than attempting to add a branch from the current 20A circuit. I know I'll have to find and remove the current branch from the overhead lighting circuit (yay! A trip to the attic in May in Georgia!).

Thanks for the advice everyone.
 
  #8  
Old 05-14-04, 12:40 PM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
Tom, thanks for the clarification. But what if it were a 20-amp circuit?
 
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
Display Modes