First time poster..i have a 4/hp 20 gallon air compressor..i tested the compressor.turned it on ran it made sure the cutoff and on switch worked..had no problem. .repeted this 5 times worked ok adj the pressure to 150.psi for cut off..then i pluged in in the garage with a 50 foot eextension cord cold start ok reached 150 cutoff as before..then i used some air..when it went to turn on again it ran very slow?? Is this because of the extension cord?or is there a problem with the compressor? Thanks for any help!!!
Air compressor and extension cord?
- Thread starter tomstr
- Start date
Charles (in GA)
Well-known member
150 is way too high for a single stage compressor. Should be about 135. While the head pressure relieves giving the compressor a chance to make a couple of revolutions, it sounds like it is loading up from the high pressure. The extension cord does not help the situation.
What gauge cord is it?
I'm assuming this is a 120v compressor, probably only about 1 to 1½ hp in reality. What does the motor list for amps on the data plate?
Charles
What gauge cord is it?
I'm assuming this is a 120v compressor, probably only about 1 to 1½ hp in reality. What does the motor list for amps on the data plate?
Charles
here is a photo
Attachments
Charles (in GA)
Well-known member
I see it says 150 psi max. The compressor will hold up better at slightly lower pressures. 150 is rather high for a single stage compressor.
When it shuts off, does it hiss and bleed off some air from the pressure switch? If it does not, it is keeping pressure on the head, making starting difficult. It should shut off and hiss loudly for a few seconds. Tank check valve could also be leaking allowing tank pressure to leak back up to the head, after the head pressure was relieved. Same effect, unable to start properly.
Charles
When it shuts off, does it hiss and bleed off some air from the pressure switch? If it does not, it is keeping pressure on the head, making starting difficult. It should shut off and hiss loudly for a few seconds. Tank check valve could also be leaking allowing tank pressure to leak back up to the head, after the head pressure was relieved. Same effect, unable to start properly.
Charles
fitz11
Well-known member
What size is the extension cord?
ditch the extension cord. your motor wants 14 amps according to the plate. your cord is probably a 16 gauge?
fitz11
Well-known member
There is no such thing as a regular cord. What gauge is it? 18, 16, 14, 12, 10? If you are using too small of a gauge you are losing voltage over the cord length potentially not providing enough to your compressor. You want at least a 14 gauge cord, I would play it safe and use a 12g
Last edited:
kams1973
ALLIANCE MEMBER
A long extention cord will cause what your are describing without a doubt.
alwaysFlOoReD
Well-known member
Yes, lose the extension cord. Voltage drop is hard on motors. If you need extensions, get extra air lines. You will lose pressure through the air lines but that is better than losing a motor.
Richard
Richard
kenburkholz
Well-known member
- Joined
- Sep 27, 2013
- Messages
- 241
Air compressor general rule; longer hose,not longer extension cord. Ken.
sberry
Banned
The size of the cord is on the jacket.
wildbill23c
Well-known member
Buy a longer hose, and don't use an extension cord. Extension cords on high-amp draw equipment is a bad thing. If you must use an extension cord buy a very heavy duty cord you'll need one with at least a 12AWG wire. The smaller the number the thicker the wire. The higher the number the thinner the wire, so when the compressor kicks on it pulls a lot of amps, and creates a lot of heat in that thin wire cord, keep doing that and you'll have an electrical fire. Best to drop the extension cord completely. I have several hoses that I can hook together if needed for longer runs. Its better not to mention quieter having the compressor sitting outside while you work inside LOL.
Zeke
Well-known member
That might be a good idea but it has nothing to do with the slow start on the cord. When you first started it it had no air therefore no load on the pump on start up when the electrical draw is the most.
If the switch was set to come back on at 100 lbs the pump had that much load to overcome and demanded even more current which wasn't there in sufficient voltage to get the motor off the start circuit. You can easily burn up a motor that way.
If you get a 50 ext cord that is 12 ga. it might work. Most don't buy those because they are 3x the money.
bcradio
Well-known member
If you're using a 'standard' extension cord on a 'standard' air compressor, then you should be fine once you switch to a 'standard' outlet.
wildbill23c
Well-known member
The heavier duty the cord the more $$ it will cost. Most people won't buy them you are exactly right, but they'll spend $1000 on an air compressor or other high amp draw device and keep burning them up
. I did finish carpentry for a while, most of the guys had junk HF direct drive oil-free air compressors. Every few months they were having to buy another one. Not just because of the junk HF compressor actually they weren't too bad, it was they would burn the motors up because they were using 18-16 gauge extension cords plugged into triple tap extension cords that were already overloaded at the jobsite. My 30+ year old Montgomery Wards 1hp/10 gal air compressor is still 100% original, I do need to replace its power cord here pretty soon as the sheathing I noticed is starting to come apart. However, I've hardly used it with an extension cord, and if it is I have a 12 gauge extension cord that I plug it into on that rare occasion. I usually just hook up another length of hose which is what I did when I was installing the new base boards in the house last week. Just 2 50' hoses got the job done, and the compressor stayed outside. If you are doing a lot of air tool use using tools that require lots of CFM, you'll want that compressor tied to an outlet, or a very expensive heavy duty extension cord or you'll be tripping breakers, and/or starting electrical fires. Possibly even burn the motor up in the air compressor as well due to the under-voltage/amp problem using a cord that's too small. My compressor will kick a 15amp breaker when the temps are really cold, once it runs a cycle though it would be fine, but I try and keep it on its own circuit whenever I can as well. That can cause issues if you try and run that compressor on a shared circuit, that may cause slow startup, where the motor doesn't come to full speed, which means it never switches from the starting circuit to the running circuit, it quickly overheats the windings and burns up the motor.
sberry
Banned
They aint putting them on an 18 cord.
never enuf time
Well-known member
I refuse to buy any extension cord that is orange. Am I alone in this ?
Op put away the electrical cord, buy a longer hose.
Op put away the electrical cord, buy a longer hose.
sberry
Banned
Why would the color matter? This is about the only place anyone really needs this kind of 12 cord and there is nothing wrong with 50 ft of it, its a trade off with the hose which is an ok idea as another section of 3/8 probably wont insult any tool a guy would run from a unit like this.
I got a couple of heavy cords, havnt used one in years except for welder, I have a Maxstar.
I love light 16 cords, I use something like that wherever I can.
I got a couple of heavy cords, havnt used one in years except for welder, I have a Maxstar.
I love light 16 cords, I use something like that wherever I can.
wildbill23c
Well-known member
LOL, pretty sure it wasn't anything more than 16AWG. Standard cheap *** electric cords is all they used. They wondered why stuff would burn up. Needless to say I was gone as soon as a better job opportunity came up. They would buy the cheapest cords they could get at HF. Yep, pretty darn sure they weren't heavy duty by any means given they were $10-20 cords.
Zeke
Well-known member
I have nothing but orange 12 ga cords. I buy them 25 feet long and chain them if I need to. I keep 4 of them in a bag and can go 100' or use up to all four for different tools off a 4-way box I carry.
I wouldn't run a 13 amp circular saw on anything but a 12 ga.
I wouldn't run a 13 amp circular saw on anything but a 12 ga.
PelicanPines
ALLIANCE MEMBER
My orange 12 is yellow... Its the only one I would use with my compressor or dewalt chop saw or table saw on a remote site.
sberry
Banned
They are ran by the 1000's daily from less without issue; Mine has a 14 on it about once when I was cutting a pallet of stock, probably never been used on a 12 and even comes with a 16 whip.
Last edited:
Zeke
Well-known member
Well, I use a Skill model 77 and it sure doesn't come with a spaghetti cord. When I pull the trigger it kicks over about an inch unless it's firmly planted. On a skinny set cord it winds up like a helicopter.
CompressorPros.com
Well-known member
Most manufacturers have an out if the air compressor motor fails and it has been running on an extension cord. Go with longer air hose and plug directly into the outlet.
DWise
Well-known member
My go to extension cord is a yellow 10 gauge. Regardless of gauge I always uncoil the cord completely.
Zeke
Well-known member
That's unnecessary. Right angles restrict, sweep bends do not. And I'm not even referring to electricity. The common thought regarding bending wire is no tighter radius than five times the gauge diameter. On 12 ga that would be a bend a little less than an inch diameter. Even if the bend radius is debatable I've never seen more that 12x the diameter. That's still pretty damn small.
Do spring coiled air lines not work? Are curly-q extension cords unsafe?
theoldwizard1
Well-known member
Big difference between a circular saw motor and a compressor motor.
Circular saws have basically "no load" at start. Compressors have some load (the crank/rod/piston) even if the head unloader is working correctly.
Also circular saws tend to have a very low duty cycle (less than 1 minute on under load and then several minutes off) where as compressors duty cycle is higher.
The load on a compressor increases at the end of it "on" period.
!4 gauge is more than adequate for a circular saw.
sberry
Banned
Yes,its the point I was making, also applied load makes some difference. So would number of cycles from a wear perspective, using a 100 of 16 on occasion to zing a 2x4 off doesn't hurt much.
I like the fact the number 13 was brought up. Its the real applied load, So many circuits are calculated using 20A, real load is less.
homemade1487
Member
- Joined
- Jul 30, 2014
- Messages
- 23
Seeing how you know how to adjust the "cutout pressure setting". The psi at which the motor turns off. I would think you could adjust the "cut in" pressure independently. For example. Have the motor shut off at 150 but when it starts back up, have it do it at 90. Most air tools are rated for only 90psi anyways. I did that to my compressor so I have less intervals inbetween filling (more cubic feet of air). But I also run a 24 cfm 2 stage pump with a 5 horse 3phase motor.