Evening from Canada…
I was curious to know how I power my 150psi pancake compressor from Walmart…I have 8 guage wire from the battery, to a 60 amp fuse, then through a 2000watt inverter, and the compressor starts up…went to 45psi…then blew the 60 amp fuse?
Any advice how to get this going for my train horns?
Thank you in advance!!
Amperage draw will increase with resistance (i.e. pressure) acting on the motor. Restarts are particularly prone to high peaks. Make sure you’re running a check valve on the output of the compressor so that the tank pressure is not acting against the piston.
What model compressor you trying to run… does it have anything on the motor in terms of ratings?
I think 8 gauge wiring is rated at 40 amp sustained load but I doubt it’s the cause of your troubles. Just keep an eye on it to ensure you don’t get the wiring running too hot.
Last but not least would be a critical look at the inverter. How many amps (peak load) is it rated for? If nothing else is running on the inverter it should be good for about 18A load or thereabouts, which might not be enough.
The other thing is to check your fuse type. Make sure you use a “slow burn” type which can tolerate some peak loads. Otherwise go for a circuit breaker.
Although I’m not trying to persuade you one way or the other, but you should probably look at running a car air compressor rather than something designed to run from mains power. Car units are better suited by design (e.g. using a short piston stroke and small air cylinder) in order to reduce the startup and torque loads.
Did the inverter come with instructions?
Here is some rough math:
2000watts / 13volts = 150amps
Thanks for the input so far…this is the compressor I am using, http://www.homehardware.ca/en/rec/index.htm/Tools/Power-Tools/Pneumatic/Compressors/Portable/6G-1-HP-Air-Compressor/_/N-ntm4z/No-48/R-I1635759?Num=1
and I was told to run a 200amp fuse and 4 guage wire to help carry the current.
Welcome to the forum.
That is definately 1/0 wire territory unless it’s a very short run.
I would NOT put a 200amp fuse on 4ga.
How long is the wire - and what brand of wire are you going to use?
No offence, but whoever told you that is crazy! Nothing in your compressor or inverter circuit should have to cater for 200 amps and putting that type of fuse in would be about as good as no fuse at all.
I had a look at the specs of your compressor and it runs 120V, with a 10A average. As I suspected, this doesn’t fare well for your inverter, which only has 2000W rating.
Although the compressor is rated at 10A, that doesn’t tell you the full picture. It will most likely draw close to double that during startup or under load. At 120V your inverter will only handle 16A (which doesn’t include the overhead of the inverter itself). Combine that with what I assume is a fast blowing fuse you’re using, and you’re not going to have much luck.
If you’re keen to experiment, go buy a circuit breaker (40A should suffice). They will only trip if there is sustained load (e.g. a short circuit) rather than blowing the instant you encounter a spike.
If you have a multi-meter you can also measure the peak loads on your circuit. Just as a tip, I’d do that on the power wire leading into your inverter rather than on the output side (less chance of zapping yourself ;)).
I doubt you need 4 AWG unless it’s over 20 feet long or you have an Oasis Compressor. Ours come with 10 feet of 4 AWG, fine strand, because that’s just right for 200 amps and it barely gets warm.
I shouldn’t have said I would not put a 200amp fuse on 4ga. Never say never, right?
I refer to a couple charts for wire sizing that are pretty conservative to the safe side. 5-10’ of 4ga is about THE longest run I would use for a 200 amp fuse. That’s good, full AWG spec OFC. Not CCA. Cheap wire that is undersized or CCA is a whole different story.
Size the fuse so it doesn’t blow from the load. Then use a wire with a higher rating for the length to be used.
It’s not always about whether the wire gets warm during use (although it’s a good indicator). The point is that - in the event of a direct short, the wire can carry enough current to blow the fuse. If not, the current will continue to flow & the wire continue to heat up, possibly melt insulation, etc…
The problem with all the charts on the internet, is you don’t know what specs they used for voltage drop, temp, etc. That’s why I use a conservative chart from a place I trust (KnuKonceptz) and 200amps does not fall in 4ga territory. But there are charts out there that say otherwise.
I looked at the chart you were referring to and it indicates that a 0-20 amp load should have #10 wire. Why then did Hornblasters ship their compressor with #12 wire? I was actually considering going back under my car and replacing the stock with that shipped with the compressor to #10 just to make sure there were no problems with overheating the wire. Before I do that I’ll try to get an amp reading with the compressor running.
Keep in mind that chart is on the conservative side. It’s on a website for a company that sells wire…and I don’t believe they even sell 12ga primary wire. The chart is geared towards higher amperage draw amplifiers & whatnot.
Didn’t you get the 540 air kit with 400C?
It says it comes with 18ft of 10ga wire.
Here is another chart: http://www.electronicsdynamite.com/graphics/wiringdiagram.jpg
Heck, here’s Viair’s chart: http://viaircorp.com/VIAIR_wiregauge_chart.pdf
You know, I’m not sure what I was thinking last night, I just looked and it appears that the wire might indeed be 10awg. I don’t know why I thought it was 12. I can only attribute it to a really long day at work. Either way I love my shockers and use them whenever I can even if no one is around. I only wish I didn’t live in the city!
I don’t mean to hijack this thread with a bunch of questions but I have one more about the Viair wire sizing chart. As we stated earlier, my kit came with 18 feet of #10awg wire. The nameplate of the compressor is 30A max. I took an amp reading and it draws about 28.5A. According to the Viair wire sizing chart the compressor should be fed with a #6awg wire to ensure that there isn’t too much voltage drop. Why is the wire that shipped with my Viair compressor undersized and should I repull a larger wire so I don’t burn up the compressor prematurely? I’m sorry if I’m worrying over little stuff but I want to make sure I don’t burn up the compressor.
Thanks for your help.
That would be a question for HB & the Viair chart does seem a little excessive.
As long as the compressor is seeing 12v while running it’ll be fine. That would be a good check to put your mind at ease.
Ok, will do. Thanks for your help. I’ll inquire with HB.
I just read this and have to comment for the OP.
First and foremost, stop what the honk you are doing with your setup right now. It’s downright unsafe, and rather obviously beyond honking retarded. Why on earth would you think that is reasonably the way to go, and safe? GOD DAMN
Can you be more specific. BTW - Welcome.
And just to be sarcastic so please don’t take this wrong but your forum name and the last statement are contradictory - do you believe in God 
Can I be more specific? How about taking the unsafe dangerous jalopy of a setup out? Power inverter, 120v pancake compressor, lengths of wire. LOL
How’s that for specific fuc king answer?
Herp derp
…and a nice warm fuzzy welcome to the forums darwinman3
