ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
VDE 0100 to introduce AFCIs
by LongRunner. 01/17/18 10:32 AM
Fujifilm Recalls Power Adapter Wall Plugs
by Admin. 01/16/18 07:04 PM
Air Compressor feeder conductor sizing
by Potseal. 01/15/18 09:08 PM
Under carpet cable?
by HotLine1. 01/15/18 09:57 AM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 30 guests, and 13 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Wiring size for a long run #22983
03/09/03 06:15 PM
03/09/03 06:15 PM
K
ksan  Offline OP
Junior Member
Joined: Feb 2003
Posts: 3
Gulf Breeze, Florida
I need to run 115 to a motor rated at 10.6 amps that is about 250 ft from the main service. The motor is the only thing on the circuit. Is 12 guage wire sufficient or should a smaller guage be used?

Work Gear for Electricians and the Trades
Re: Wiring size for a long run #22984
03/09/03 06:51 PM
03/09/03 06:51 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
Using a voltage drop calculator I got on the Web and the info you gave you will have voltage drop of 10.5 volts or 9.2% if you use #12

#10s would be 5.5% drop or 6.3 volts
#8s would be 3.5% drop or 4.0 volts
#6s would be 2.2% drop or 2.2 volts


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Wiring size for a long run #22985
03/09/03 10:26 PM
03/09/03 10:26 PM
B
Bjarney  Offline
Moderator
Joined: Apr 2002
Posts: 2,527
West-Southern Inner-Northeast ...
Not wanting to throw a wrench in the gears, remember that for motors, one needs to also consider starting voltage drop. A rule of thumb for starting is 15% maximum. This is why 230 and 460V motors become attractive.

{Note that starting voltage drop is not a Code requirement, or even an FPN. Overlooking it can cause problems, and is commonly part of the commercial and industrial design process.}




[This message has been edited by Bjarney (edited 03-09-2003).]

Re: Wiring size for a long run #22986
03/09/03 10:34 PM
03/09/03 10:34 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
Bjarney, not a wrench in the gears but do you apply the 15% to the FLC, so 10.6 x 1.15 = 12.19 amps and then apply the voltage drop calcs. And does 15% work for all voltages.

Bob


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Wiring size for a long run #22987
03/09/03 10:54 PM
03/09/03 10:54 PM
E
Edward  Offline
Member
Joined: Dec 2002
Posts: 308
California
Check to see if you can wire it to 240 Volt
If you can then use 240 Volt connections and use 8 AWG wires.

Edward


Thanks
Edward
Re: Wiring size for a long run #22988
03/10/03 11:56 PM
03/10/03 11:56 PM
F
frenchelectrican  Offline
Member
Joined: Feb 2003
Posts: 939
Wi/ Paris France { France for ...
ok i look at my electican calculator and for 115 volts appactions for that kind of distance i recomoned #10 is minumin wire size other wise if the moter can change to 230 volts. if so all by the mean go for 230 volts and i got one note from power company say any electric moter over 1 1/2 hp will like to keep on high side (voltage) due less stress at the transformer and line effcts and btw most motors dont like to start when voltage get too low ( i have alot of sevrvice call with waterwell pumps and came with way too small a wire size )


merci marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Re: Wiring size for a long run #22989
03/11/03 06:38 PM
03/11/03 06:38 PM
B
Bjarney  Offline
Moderator
Joined: Apr 2002
Posts: 2,527
West-Southern Inner-Northeast ...
iwire — Sorry for the slow follow-up. Motor starting current is usually something like 6xFLC.


Featured:

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

 

Member Spotlight
renosteinke
renosteinke
Blue Collar Country
Posts: 5,316
Joined: January 2005
Show All Member Profiles 
Top Posters(30 Days)
sparky 23
Admin 20
Potseal 13
Popular Topics(Views)
243,527 Are you busy
180,329 Re: Forum
170,821 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.035s Queries: 14 (0.014s) Memory: 0.9834 MB (Peak: 1.1368 MB) Zlib enabled. Server Time: 2018-01-17 21:46:17 UTC