As a user of an electric chainsaw and splitter, I've read with interest the many opinions expressed here and elsewhere about the virtual necessity to use 10 guage extension cord for anything 50 feet and longer, in order to mimimize power losses. So I decided to do a test to see if it really does make a difference.
For the past two years I've used a 75 foot 14 guage extension cord that I built using better components than the store-bought stuff, and it's worked fine. I didn't really want to go plunk down over a hundred bucks just to do this experiment (10/3 goes for over $1.50 a foot here). Luckily, last week I found four pieces, 70 feet total, of neoprene-jacketed 10/3 in amongst the mounds of electronic surplus in my warehouse. This morning I spliced them together with tinned copper wire splices, crimped and soldered all the joints to minimize contact resistance loss, and double heatshrinked the unions for durability.
From the charts, 75 feet of #14 has a resistance of 0.180 ohms, and 70 feet of #10 has a resistance of 0.071 ohms, a factor of about 2.5 difference. On the face of it, those numbers don't sound high enough to be significant. But the total AC loop resistance is actually 0.360 and 0.142 ohms respectively. And those numbers are getting high enough where their difference might be influential in a 15-amp draw situation. The question is - is it noticeable in use?
By the way, I'm not concerned about voltage drop across the wire, it's the current loss through the resistance that would be the bigger power loss.
I'll be testing it this weekend with a 15 amp splitter (Task Force) and 13 amp saw (Makita UC4000). Stay tuned for results.
For the past two years I've used a 75 foot 14 guage extension cord that I built using better components than the store-bought stuff, and it's worked fine. I didn't really want to go plunk down over a hundred bucks just to do this experiment (10/3 goes for over $1.50 a foot here). Luckily, last week I found four pieces, 70 feet total, of neoprene-jacketed 10/3 in amongst the mounds of electronic surplus in my warehouse. This morning I spliced them together with tinned copper wire splices, crimped and soldered all the joints to minimize contact resistance loss, and double heatshrinked the unions for durability.
From the charts, 75 feet of #14 has a resistance of 0.180 ohms, and 70 feet of #10 has a resistance of 0.071 ohms, a factor of about 2.5 difference. On the face of it, those numbers don't sound high enough to be significant. But the total AC loop resistance is actually 0.360 and 0.142 ohms respectively. And those numbers are getting high enough where their difference might be influential in a 15-amp draw situation. The question is - is it noticeable in use?
By the way, I'm not concerned about voltage drop across the wire, it's the current loss through the resistance that would be the bigger power loss.
I'll be testing it this weekend with a 15 amp splitter (Task Force) and 13 amp saw (Makita UC4000). Stay tuned for results.
