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trader_4 trader_4 is offline
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Default Generator Cord Sizing 100' Run: Stay With 10-Gauge?

On Sunday, July 27, 2014 3:17:32 PM UTC-4, wrote:
On Sun, 27 Jul 2014 12:06:56 -0400, "(PeteCresswell)"

wrote:



Been using a 10-gauge cord to connect my little 2kw gennie in the garden


shed to the transfer switch in the garage.




No problems in maybe 20 hours total usage and the numbers look right per


http://tinyurl.com/nvkyq32, which says the voltage drop will be 2.5% at


full load.




My understanding being that the voltage drop should be less than 5% at


full load.




Now I am going to add a second 2kw and run them in parallel. (Honda


EU2000i + EU2000i Companion). viz: http://tinyurl.com/pjwqxbp




In outage mode, the house cruises on 800-1200 watts so 95% of the second


gennie's function will be redundant backup in case there's a problem


with one unit during an outage.




But since I will have two.... why not? Then we could fire up both


during mealtimes and accommodate a toaster or a coffee maker... or the


kitchen's big microwave.




With the two units connected in parallel, the power cord interface


changes from a regular 3-prong plug to a 30-amp L5-30 twist-lock plug.




Running the numbers (Copper wire, 10 AWG, 120v, AC single phase, single


set of conductors, 100' distance, load current 30 Amps) into


http://tinyurl.com/nvkyq32, I get a voltage drop of 5.99 (4.99 percent).




Less than the 5% limit - and, real-world, not just .1% less because the


two gennies will never be putting out a full 30 amps.




I'm thinking I can keep using the current 10-gauge cord by making up an


adapter with a female 3-prong receptacle on one end and an L5-30 male


plug on the other end.




That way, one cord does it whether I use one gennie or two; cord


winding/storage remains merely inconvenient instead of becoming


difficult; and I avoid shelling out $250-$300.




Anybody see a flaw in this reasoning?


As long as you are never drwing 30 amps from the generator the cord

will be "adequate". If I was setting up fresh I would buy a heavier

cord - but what you have will continue to do the job.


Again, I don't see how you could ever draw 30 amps from a 4KW generator
on any one conductor. AFAIK, you can only do half of that.