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ligito
06-18-2009, 09:56 PM
I bought a Quincy 2V41C60VC.
Single phase-2 stage-220 volt.

I think it needs a 30 amp breaker.
I only need to run about 35 feet of wire in 3/4 conduit.
Should I use 10 Ga, or 8 Ga (as someone else suggested in another post)?
The specs for compressors, motors etc., are very well hidden from the public, it seems.

I don't see very much voltage drop, so which is preferable?

knedvecki
06-18-2009, 10:55 PM
Wiring Simplified by Richter/ Schwan / Hartwell (available at your local Home Depot for about $5.50 US) says 10 ga is good for 2 % voltage drop at 240 volts single phase for up to 75 feet. Ugly's Electrical References ( also at Home Depot) says up to nine conductors of 10 ga size in Rigid Metal Conduit. Best to just get these books.
Regards, Keith

ligito
06-18-2009, 11:23 PM
I have the book but between ambiguity and differing opinions, I always ask questions, anyway.

Quincy says to use isolation pads to bolt to the concrete.
Do most people also do that, to cut down on noise and vibration?

Jim Shaper
06-18-2009, 11:57 PM
Mine was loosely bolted to a pair of 4x4 skids and has never moved in the 2 years I've been running it like that. From the looks of the timbers, they've been there since it was new in 1983.

I too have a 5hp single phase motor, and ran 10ga with no problem. Unless your duty cycle is high (probably not the case), you wouldn't even gain peace of mind going with the 8ga.

radkins
06-18-2009, 11:58 PM
Quincy says to use isolation pads to bolt to the concrete.
Do most people also do that, to cut down on noise and vibration?



It will cut down on tank cracking! If you mount the tank solid to a concrete floor you risk cracking it where the mounting feet weld to it, this is due to the vibration. It will not happen quickly but it is very possible after a while and that Quincy is very likely to be running for a LONG while! :)

Boucher
06-19-2009, 01:29 AM
First let me say that #10 is adequate and over the years I have created a lot of problems for myself trying to terminate large wire in small pressure switches etc. ---- I would run the #8 and take it to a magnetic contactor rated for 50 amps. Then run a #14 from the contactor coil to the pressure switch and / or to a switch inside the shop for deactivating the compressor. The electrical contact points are the weak link in the chain. Contactors are not that expensive from Grainger. I like to mount the contactor in a larger old water pump control box. This can be sealed to keep out ants spiders and wasps. The whole top comes off with one screw to allow better access if needed.

Boucher
06-19-2009, 01:44 AM
These don't have to be fancy. Enco sells some rubber sheet material with ribs running perpendicular to one another on opposite sides. That is what I used . Simple wooden blocks of fairly soft wood would work. I would bolt it down but just snug the bolts.

doctor demo
06-19-2009, 02:25 AM
I have the book but between ambiguity and differing opinions, I always ask questions, anyway.

Quincy says to use isolation pads to bolt to the concrete.
Do most people also do that, to cut down on noise and vibration?
Just throw a mud flap under it and forgetaboutit:D unless ya think it is going to fall over:eek:

Steve

Jim Shaper
06-19-2009, 02:45 AM
Byron makes a good point about the contacts in the pressure switch. I did exactly the same thing and wired a magnetic contactor (motor starter) between the line and the switch. This takes the motor load off the pressure switches small contacts and moves it to the mongo pads in the contactor.

Dragons_fire
06-19-2009, 10:46 AM
i left my 60gal upright on the pallet it came on, and just screwed a few hockey pucks under it. makes it a lot quieter and when i move to a bigger shop, its still on the pallet aand ready to go!!

ligito
06-19-2009, 12:50 PM
I have a 60 gallon tank sans compressor, that I cut the pallet down to a smaller width and bolted it on.
The tank alone doesn't vibrate though.:D

Quincy says to bolt it to the floor on isolators, leave the nut a little loose and double nut it. Does this also sound like good advice, or should I just bolt it to the pallet in the same manner and maybe strap it to a wall?

radkins
06-19-2009, 12:53 PM
Most outfits don't recommend leaving them on the wooden pallet but I can't understand why not. I know one that has been sitting on the pallet it came on for nearly 18 years now and it has not been a problem at all. I have seen several more left on the pallets and although they have not been running for 18 years yet they still seem to be working out just fine. I suppose it would be a matter of just how well the pallet is built but that should just be simply a matter of inspecting the thing to determine if it is flimsy or substantially built.

radkins
06-19-2009, 01:01 PM
Quincy says to bolt it to the floor on isolators, leave the nut a little loose and double nut it.


That sounds like an excellent way of doing it and for a good reason, that's what is generally recommended. Actually bolting it to the floor may be a bit of over-kill unless it tries to "walk-around" when running or is in danger of being knocked over but neither of these situations is likely. If the pallet is heavily constructed of hardwood then just leaving it on the pallet would most likely be just fine but it is easy to see why a manufacturer would hesitate to recommend this, a good alternative to the pallet would be the rubber pad. If you decide to leave it on the pallet then it will be up to you to determine if it is heavy enough but if you want to do this RIGHT then follow the manufacturer's directions and you can't go wrong!

Lu47Dan
06-19-2009, 02:18 PM
All the air compressors that I have installed while working as a pipefitter have been bolted down to the pad they are setting on . A horizontal compressor is unlikely to tip over , but for worker safety and insurance purposes they are required to be mounted so they can not move . If you live in an area that has earthquakes then it would be best not to leave them on the skid especially if it is a vertical model as they are top heavy and more likely to tip over .
Vibration isolation pads help prevent stress build up in the legs of the tank but also reduce the annoying vibrations transmitted into your floor when the compressor is running .
One thing no one has mentioned here is leveling the compressor , since the majority of "home" sized compressors are splash lubricated then an out of level condition can effect the life span of the pump by reducing the available oil to the rod bearings . I know this sounds picky but I have seen good compressors ruined because of shoddy installation . You don't need to put a machinists level on it but getting it within the level lines is a good preventive measure when you set it up .
Now putting a magnetic starter on it will save your pressure switch and give you larger contact area while running . As to wire size I would go with the 8ga instead of the 10ga , if you expect long running times . But that is just me .:D
Dan

JeffKranz
06-19-2009, 02:54 PM
About 10 years ago, I installed a 60 Gallon Vertical Tank compressor and it has been on the pallet it came on and that sits on top of a car tire (rim removed). Actually the tire was in great shape and free from the local tire shop with a hole in the sidewall.

Jeff

radkins
06-19-2009, 03:01 PM
Another killer of compressors that rarely gets mentioned is freezing weather. If a compressor is left in a freezing area and moisture has accumulated in the lines to the unloader valve then motor damage can occur. What happens is when the compressor shuts down it is supposed to bleed off the pressure from the pump and the supply line to the tank (there is a back-flow valve in the tank to prevent air from flowing back into the pump), that is the hiss you hear when it shuts down after reaching pressure. If this line gets plugged with ice, and I have seen this happen more than once, it will not bleed off the pressure so when the compressor kicks back on the pump will be under a load. It takes a great deal more torque to start the pump turning under a load than it does with no pressure on it and this puts undue stress on the motor, sometimes even to the point of stalling it out. Even if it does not stall it can be damaged from a starting load it is not designed to handle.

ligito
06-19-2009, 07:33 PM
Then what do you do in an unheated, unattached garage, leave a light on by the unloader?

radkins
06-19-2009, 10:24 PM
Then what do you do in an unheated, unattached garage, leave a light on by the unloader?



Just watch it through the first charge cycle and make sure the unloader works if the conditions are such that it could freeze. This rarely happens but unfortunately it DOES happen sometimes so it should be considered if the compressor is left for idle for several hours in freezing conditions. Usually what happens is it will simply trip the breaker but if it does not the motor will usually exhibit some signs of an overload on start-up.

ligito
06-20-2009, 12:09 AM
First let me say that #10 is adequate and over the years I have created a lot of problems for myself trying to terminate large wire in small pressure switches etc. ---- I would run the #8 and take it to a magnetic contactor rated for 50 amps. Then run a #14 from the contactor coil to the pressure switch and / or to a switch inside the shop for deactivating the compressor. The electrical contact points are the weak link in the chain. Contactors are not that expensive from Grainger. I like to mount the contactor in a larger old water pump control box. This can be sealed to keep out ants spiders and wasps. The whole top comes off with one screw to allow better access if needed.

My compressor doesn't use a magnetic starter because it has capacitor start but would I benefit from running #8 from the breaker to the magnetic starter and then #14, Or #10 to the pressure switch?

Wouldn't this also provide me with a means to shut it off that I coul place near my entry door?

Lu47Dan
06-20-2009, 10:35 AM
My compressor doesn't use a magnetic starter because it has capacitor start but would I benefit from running #8 from the breaker to the magnetic starter and then #14, Or #10 to the pressure switch?

Wouldn't this also provide me with a means to shut it off that I coul place near my entry door?
First , the starter can be used with a capacitor start motor , the starter uses a electromagnetic switch to make or break the connection , basically a heavy duty relay . The wiring currently run to the pressure switch would be run through the starter and a separate circuit would replace them . This circuit could be of a lower voltage , it would be the control circuit . The pressure switch would only control the coil in the magnetic switch , and the load of the motor would be handled by the contacts in the magnetic switch which are larger then the contacts in the pressure switch .
Second , 8 ga if it will handle the load would be better than a 10 ga for power to the compressor .
Third , if you need a way to start/stop the compressor a simple switch that would break the control circuit could be installed at the door but a way to disconnect the main power would have to be installed at the equipment if the equipment is out of sight of the main panel .
Dan

ligito
06-20-2009, 04:11 PM
My compressor is less than 20 feet from my service panel.
I just bought 25 feet of 10 Ga Red , Green, Black THHN, for $.38 foot at Home Depot, then went to a local electrical supply that is quitting business and got about 250 ft of 10 Ga Green ground for $.09 foot ($21.00).
I'll use it eventually.

I think I will get a switch (commercial equipment on/off switch) and wire it, while I'm looking for a magnetic switch.

ligito
06-20-2009, 08:30 PM
First let me say that #10 is adequate and over the years I have created a lot of problems for myself trying to terminate large wire in small pressure switches etc. ---- I would run the #8 and take it to a magnetic contactor rated for 50 amps. Then run a #14 from the contactor coil to the pressure switch and / or to a switch inside the shop for deactivating the compressor. The electrical contact points are the weak link in the chain. Contactors are not that expensive from Grainger. I like to mount the contactor in a larger old water pump control box. This can be sealed to keep out ants spiders and wasps. The whole top comes off with one screw to allow better access if needed.

Any idea of a Grainger part number?

Boucher
06-24-2009, 05:08 PM
The Grainger part # that I have in stock is 5B111 this shows to be 40FLA 50A Res. This is what I have in stock now. I may have used slightly heavier. I have been retired since 2003. My 2005 catalog shows $37 cost. I sure didn't remember it costing that much. One local source that I found was the local Air Cond Electrical Supply house. Their contactors were a lot cheaper but use 24 volt coils. 24 volt transformers are cheap at The Surplus Center. They may also have contactors that would work also.

Sorry to be slow responding. I got sidetracked to the hospital and got a new switch installed (Pacemaker)

ligito
06-24-2009, 05:57 PM
Thanks Byron

This must be it: http://www.grainger.com/Grainger/items/5B111?time=Wed+Jun+24+16%3A01%3A38+CDT+2009

Would the 1V608 30A be a closer match? It's on the bottom right of the Grainger web page.

Do you just wire the hot leads from the starter to the compressor and wire the ground separately?
What can I use for an on/off switch?
I can probably get it from Grainger also but don't know how to find the right one?
I seem to remember Cutler Hammer making a lot of those switches for equipment.