Although I haven't purchased the air compressor yet, I think I'm sold on the 240V vertical variety. In typical fashion I over-design everything for the just-in-case factor. So I've run #10 Romex to the compressor location but I want to be doubly sure that's big enough.
Only problem is: I can't find the current draw for any of the systems out there. I spent an hour of fruitless online search last night and the only info with current draw posted online that I found was for Porter Cable. Nothing for Ingersoll Rand, Campbell Hausfeld, Husky, Kobalt, Craftsman, etc.!!!! Porter Cable's largest 80 gallon dual stage (which is probably bigger than I need or want even if I will paint the plane myself) is rated at 30 amps. But is this continous or startup?
So will you check my math for me?
According to the calculator on http://www.southwire.com (makers of Romex) #10 wire at 240V will have 3% voltage drop (recommended max) at 30 amps over 114 ft.
But my run is only 50 feet so according to Method #1 I should be good for 30 amps.
Method 2: Again using the southwire calculator for minimum conductor size: #10 wire at 240V at 30 amps over 50 feet will sustain a 1.32% voltage drop. So I'm good there.
Method #3: Good ol' Electricity 101: 240V x 30amps = 7200 Watts = 9.6 electric horsepower according to http://www.onlineconversion.com
What I don't know about method #3 is that most of the larger compressors will state 7 hp continuous. But do they have a higher power requirement (translated higher current draw) during startup? For the life of me, I can't find this information out online.
So for now, it looks like my #10 wire should be good for 30 amps at 240V at my 50 ft. But the question still remains: What is the maximum current draw during startup on these 80 gallon dual stage (worst case) compressors????
Or do I need to pull out my #10 wire and use #8 instead?
Only problem is: I can't find the current draw for any of the systems out there. I spent an hour of fruitless online search last night and the only info with current draw posted online that I found was for Porter Cable. Nothing for Ingersoll Rand, Campbell Hausfeld, Husky, Kobalt, Craftsman, etc.!!!! Porter Cable's largest 80 gallon dual stage (which is probably bigger than I need or want even if I will paint the plane myself) is rated at 30 amps. But is this continous or startup?
So will you check my math for me?
According to the calculator on http://www.southwire.com (makers of Romex) #10 wire at 240V will have 3% voltage drop (recommended max) at 30 amps over 114 ft.
But my run is only 50 feet so according to Method #1 I should be good for 30 amps.
Method 2: Again using the southwire calculator for minimum conductor size: #10 wire at 240V at 30 amps over 50 feet will sustain a 1.32% voltage drop. So I'm good there.
Method #3: Good ol' Electricity 101: 240V x 30amps = 7200 Watts = 9.6 electric horsepower according to http://www.onlineconversion.com
What I don't know about method #3 is that most of the larger compressors will state 7 hp continuous. But do they have a higher power requirement (translated higher current draw) during startup? For the life of me, I can't find this information out online.
So for now, it looks like my #10 wire should be good for 30 amps at 240V at my 50 ft. But the question still remains: What is the maximum current draw during startup on these 80 gallon dual stage (worst case) compressors????
Or do I need to pull out my #10 wire and use #8 instead?
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