ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Anybody Remember this?
by Bill Addiss - 08/17/19 09:07 PM
Fuse blower plug?
by Bill Addiss - 08/17/19 09:01 PM
100 year old Light Bulb
by Bill Addiss - 08/17/19 11:44 AM
1897 paper on 110-220 incandescent lamps
by ghost307 - 08/15/19 10:31 AM
Forum Updates Coming Soon.
by Admin - 08/08/19 11:50 PM
New in the Gallery:
What is this for?
Plug terminals
Who's Online Now
0 registered members (), 10 guests, and 12 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
disposer/dish circuit #154392 07/06/05 01:41 AM
Joined: Mar 2005
Posts: 233
watersparkfalls Offline OP
Member
i want to know if anybody can help me calculate if i can put a 1/2 HP disposer motor and a dishwasher that draws a nameplate or 9.1 amps on a 20 amp circuit.

Building Codes & Related References
Re: disposer/dish circuit #154393 07/06/05 12:39 PM
Joined: Jul 2004
Posts: 9,381
G
gfretwell Offline
Member
Nominal FLA on a 1/2 HP motor is 9.8a (plus 25%) added to 9.1a seems to be too much for a multiple motor load.
If you are cord and plug connected they each do represent less than 50% of circuit ampacity so it might be "hold your nose" legal. I have seen this go both ways but the preferable solution is a multiwire circuit with 2 phases feeding the duplex.


Greg Fretwell
Re: disposer/dish circuit #154394 07/07/05 02:12 AM
Joined: Mar 2005
Posts: 233
watersparkfalls Offline OP
Member
thanks gf i just wondered if possible...
could you elaborate on the 50% since cord connected dishwashers are feasible and do provide disconnecting means for motor.

h2o

Re: disposer/dish circuit #154395 07/07/05 12:39 PM
Joined: Jul 2004
Posts: 9,381
G
gfretwell Offline
Member
It all gets down to how you read
210.23(A)(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.

Most inspectors would say all fixed in place equipment must be less than 50% but I have seen this stretched to say any one piece can't exceed 50%, particularly on an intermittant load like a disposal.
Vote me for "all".


Greg Fretwell
Re: disposer/dish circuit #154396 07/07/05 10:03 PM
Joined: Jan 2005
Posts: 5,316
renosteinke Offline
Cat Servant
Member
One caution here....look at the FLA on the disposal, and not the "horsepower" rating. I have seen a lot of inflated "horsepower ratings" over the years.

Re: disposer/dish circuit #154397 07/12/05 09:46 PM
Joined: Feb 2005
Posts: 693
L
Larry Fine Offline
Member
"...lighting units (or) cord-and-plug-connected utilization equipment not fastened in place..."

Neither describe either a dishwasher or a disposer, so 210.23(A)(2) doesn't apply.

I routinely place both of these on a 20-amp circuit. A disposer is probably the epitome of an intermittent load.


Larry Fine
Fine Electric Co.
fineelectricco.com
Re: disposer/dish circuit #154398 07/12/05 09:55 PM
Joined: Feb 2005
Posts: 693
L
Larry Fine Offline
Member
According to Insinkerator specs, the 1/2HP Badger 5 has an average current draw of 6.9A.
http://www.insinkerator.com/pdf/badger5.PDF


Larry Fine
Fine Electric Co.
fineelectricco.com
Re: disposer/dish circuit #154399 08/10/05 09:27 AM
Joined: Apr 2005
Posts: 73
D
dlhoule Offline
Member
Good subject. I have been told that they make a 3 way switch that can be used in these applications. One position for dishwasher and other for disposal. Now having said that I personally have not seen one. Do they make them?

Re: disposer/dish circuit #154400 08/10/05 10:23 AM
Joined: Oct 2004
Posts: 135
B
BobH Offline
Member
Any 3-way rated for the load would work.

Re: disposer/dish circuit #154401 08/10/05 05:43 PM
Joined: Aug 2003
Posts: 1,374
R
Ryan_J Offline
Moderator
I am moving this to the NEC section.


Ryan Jackson,
Salt Lake City

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
richard
richard
L.I. New York
Posts: 99
Joined: August 2003
Show All Member Profiles 
Top Posters(30 Days)
Admin 16
GeneSF 8
Popular Topics(Views)
257,828 Are you busy
193,565 Re: Forum
183,204 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3