3000W Chinese Gensets Info.
professor95 wrote: EDIT ADDED 45/5/2013- When this thread started in March of 2005, I never expected to see it survive this long or amass the quantity of information that has been shared here. In...
Forum Discussion
BORoarke wrote:
We will be using the champ to run our 13,500 A/C unit and the microwave. We plan on buying a 30amp extension cord. Could someone please help me understand what kind of power loss we can expect by connecting a 50 ft 30amp extension cord to our RV cord that came with the RV (I think its probably 15 to 20 ft)? Will we drop a lot of power from the length? What is the rule of thumb for loss/length.
#10 copper has a resistance of 1.02 ohms per 1,000 feet. You are considering a length of 70 feet. The resistance for 70 feet will be .0714 ohms.
Using "Ohm's Law" (voltage = current in amperes x resistance in ohms) we will assume 30 ampres x .0714 ohms. The voltage drop will be slightly over 2 volts (2.142). The resistance actually converts the electrical energy to heat in the cable.
The maximum recommended length of #10 cable at a 30 amp load (120 volts) is 38 feet.
Keep in mind you WILL NOT be consistently pulling 30 amps. IMPO, you will be OK with 70 feet total. Just don't exceed that length to be safe.
Also, keep in mind that at 7,000 feet you will not be able to pull full current from the generator. Their ratings are at sea level. Your engine will not produce full power at that elevation. You should have enough Horse Power to run the AC, but I would be surprised if you could power both the AC and microwave at the same time.
As far as my numbers are concerned, I suggest you try to pick up "The Pocket Reference" by Thomas J. Glover, Sequoia Publishing, http://www.sequoiapublishing.com
The cost is about $10 and it will give you more information on electrical, lumber, plumbing, etc. than you will ever need. You might find one at Lowe's or Home Depot. It is a little black book.
