Need help with an air compressor

[wendlwacker]

So this air compressor came from my dads processing plant. It was replaced with a 3 phase quincy compressor. It has been sitting in the back of the warehouse for several years. Well I finally got my first house with a 30'x30' insulated shop and I convinced my dad that I could give it a great new home. I know nothing about this air compressor and my dad had nothing to do with the purchasing of it the first time. So i need some help! I would like to find a manual for it or at least someone that can tell me how to operate this thing. It is my first air compressor and yes I know it is WAY oversized but you can't complain for free.99 can you?

My thinking for this compressor is that you can see a 220 50 amp outlet hanging in the back ground. I have yet to get it permanently mounted as I am working on where exactly I want it to go. My plan is that I only have the ability to have one 220 50 amp breaker in the garage and I also have a welder that I hook up to the outlet. So I want to hook the compressor up with a plug so I can swap back and forth between the welder and the compressor. This will also keep me from overloading the electrical in the garage since I could only use one or the other at a time. And let's be honest I could let the tank fill, switch to the welder and still have enough air for air tools for a brief while!

So who can give me info! I am also looking for suggestions for a good halfway inexpensive set of airtools remember I just bought a house but I am not scared to purchase quality.

 

[wendlwacker]

No one has any idea what this is? or if I can wire it to a plug?

 

[zkling]

So after a bit of googling. I was able to turn up this spec sheet. Looks like a pretty decent compressor.

http://www.c-aireinc.com/Fact Sheet PDF/CK410822-30V5.pdf

I'm personally not familiar with that manufacture of compressor. Looks like it has a 5hp motor on it. Yes the 50 amp breaker you have for your welder will be just fine. You could just slap a proper (nema 6-50P) plug on the compressor and you will be should be fine. HOWEVER, technically the 6-50P plug/recptical has max HP rating of 3hp, which is less than the motor on your compressor. The proper way would be to direct wire the compressor to a 50 amp breaker with a motor and amperage rated disconnect between.

I will let you decide which route to take. But whatever you do, PLEASE properly mount that 50 amp receptical, instead of just letting it dangle there by it's CORD to the box.

As for the air tools. What kind of air tools are you looking for? Almost all of my air tools are cheap china , except for a 1/4 mac ratchet that I lucked into a few years back. There is always the used route. For the money new, the HF earthquake impact guns and their HVLP spray guns are good.

 

[kams1973]

That unit looks like a rebranded Rol-Air compressor

 

[bsaint]

That unit looks like a rebranded Rol-Air compressor

Yea a K17 or K18 pump.

 

[CNGsaves]

Is . . Bob's Tools . . . still in business??

Appears that's the local shop who sold the compressor??

 

[scw1991]

if it's only a 5HP motor, that means it will pull about 22 amps per leg which is far less than what the 50 amp breaker is rated for (50 amps per leg). 8 gauge wire would be ample and you could use a 30 amp dryer outlet cord for that matter wired into the magnetic motor starter.

http://www.sears.com/sears-3-wire-6...1x000001&kpid=02649787000&kispla=02649787000P

 

[zkling]

if it's only a 5HP motor, that means it will pull about 22 amps per leg which is far less than what the 50 amp breaker is rated for (50 amps per leg). 8 gauge wire would be ample and you could use a 30 amp dryer outlet cord for that matter wired into the magnetic motor starter.

http://www.sears.com/sears-3-wire-6...1x000001&kpid=02649787000&kispla=02649787000P

True, but since the OP wants to put it on a plug and be able to switch between the welder and air compressor. As I mentioned above, technically a 50amp plug is (nema 6-50) is only rated to 3hp and a 30 amp dryer plug (10-30) is only rated to 2hp. Due to the start up amps the motors can pull. Both of which are less than the 5hp motor on that compressor.

 

[scw1991]

True, but since the OP wants to put it on a plug and be able to switch between the welder and air compressor. As I mentioned above, technically a 50amp plug is (nema 6-50) is only rated to 3hp and a 30 amp dryer plug (10-30) is only rated to 2hp. Due to the start up amps the motors can pull. Both of which are less than the 5hp motor on that compressor.

Please advise where you are getting specs on a 6-50 amp plug. Is it not rated for 50 amps? That is equal to 50 amps per leg and there are 2 legs on a 230v/1ph circuit. You could run a 10HP 230v/1ph/60 motor as it will only draw about 43 amps. Start up amperage draw has nothing to do with sizing the circuit. An electric motor can easily pull 6x the motor nameplate amperage at start-up, but it is only momentary.

If he wants to run a welder that pulls in excess of 30 amps per leg, then he should install a 50 amp receptacle. Both compressor and welder would have a 50 amp plug.

 

[zkling]

Please advise where you are getting specs on a 6-50 amp plug.

First one I could find, quickly.

http://www.afielektrik.com/PDF/urunler/HUBBELL-WIRING/X.pdf

 

[scw1991]

Well.......I'll.......be.......damned!

I owe you one large apology there Mr. zkling!

Ok then....why is it de-rated then to run a motor? Is it assuming there would be arcing when motor is plugged/unplugged from circuit? This is interesting and I embrace education on these types of subject matters.

 

[Charles (in GA)]

Motors have very high start draw. For a few miliseconds, the amp draw is outta sight. My 7.5 hp which draws 30ish amps running, draws a peak of 190 amps for a split second. The plug and receptacle could handle it a few times, but eventually there would be problems. Since the ratings are designed for permanent, continuous use, the manufacturer derates it for motor use.

OP could do something temporary, but I know from personal experience, temporary usually becomes permanent, so he needs to bite the bullet and get the right hook up.

Charles

 

[firebox40dash5]

Unless you're planning on moving it around lol why not hard-wire it right, to the box that appears to be right next to where it's gonna be? For about as much as you're gonna spend on the right plug you could have a dedicated breaker and the wire to hook it up, and turn it off that way if you feel the need.

 

[wendlwacker]

So could I just hardware the compressor with the same wire I have coming out of the box and then put a junction box with plug one way and hard wired cord the other to the compressor? This wouldn't keep someone from using both at the same time but would that be more kosher?

 

[firebox40dash5]

So could I just hardware the compressor with the same wire I have coming out of the box and then put a junction box with plug one way and hard wired cord the other to the compressor? This wouldn't keep someone from using both at the same time but would that be more kosher?

Question the first... do you have (or can easily make) 2 adjacent breaker spots in there? How much load in it already, and what's the limit? Adding a breaker is too easy if you've got room. And if not you can probably either move breakers or use tandems... if you've got more capacity than physical space.

Failing that, I'd junction what you've got in a larger enclosure, and run new wire in a larger enclosure... nailed to the wall this time.

 

[R.Anderson]

You should consider upgrading to a larger service panel if you can.

 

[wendlwacker]

1) no more room in the panel....

2) If I knew I was going to be here for a long time i would have no problem fixing it right. BUT i have no idea how long I could be here. It was supposed to be for several years and my boss called me today about a new position. So I am fixing things in the house right but not necessarily in the best way.

3) you guys are making me feel terrible for not mounting the plug yet! lol the breaker is off on the plug fyi