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#16 skoughi

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Posted 25 May 2013 - 08:28 AM

Was wondering about having two small compressors, say a couple of 2hp's and plumb them together ie an outlet airline from each into a t piece then into a regulator and wire them into one preasure switch so when the tank preasure drops enough to switch on power then they both start at the same time and switch off at the same time. So in theory you could increase the cfm by buying a smaller and cheaper second compressor to help with one you already have thats not quite up to it.

#17 Tomm

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Posted 25 May 2013 - 12:10 PM

If you have a separate garage and shed I would advise keeping the compressor in a separate shed.

 

When I first started painting I kept mine under my work bench, when I would paint it would start up when I was nearly finished and when it did started up it would shake all of the dust and grime off it, up into the air and all over what I just painted.

 

Lesson leant and it went in the container outside.



#18 Daz1968

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Posted 25 May 2013 - 02:03 PM

Connecting 2 compressors is best way to get more output, just set pressure switches so they don't start at same time to reduce load on electrics. I am planning on running my 3hp and a 2hp to increase capacity.

#19 skoughi

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Posted 25 May 2013 - 05:26 PM

Surely if the preasure switches were set at different settings then the one that is set at the highest setting would be the only one that would start as that would be the lowest preasure that both tanks would get to. If both tanks are connected then they would always be at the same preasure. Would it not be better to have some sort of electrical delayed timer on one of the compressor motors? Power would go to both of them at the same time when both tanks hit the low preasure setting then one would start followed by x amount of seconds then the second one kick in. I'm presuming you can get an electrical delayed timer switchthingamejig! 



#20 AVV IT

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Posted 25 May 2013 - 06:49 PM

 

 

I just bought one of these for the garage to power guns, die grinder and small HVLP for spraying blocks etc...  More than up to the job, very portable, small foot print and very keenly priced....

 

https://www.facebook...&type=1

 

 

 

That looks like a really good idea. I've often thought about upgrading to a bigger compressor, but with a small single domestic garage, I really don't want to loose all the extra space that a bigger one will inevitably take up. This upright version could well be the answer though!!  :thumbsup:

 

How does it cope with air tools? :unsure:



#21 sonikk4

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Posted 25 May 2013 - 07:06 PM

 

 

 

I just bought one of these for the garage to power guns, die grinder and small HVLP for spraying blocks etc...  More than up to the job, very portable, small foot print and very keenly priced....

 

https://www.facebook...&type=1

 

 

 

That looks like a really good idea. I've often thought about upgrading to a bigger compressor, but with a small single domestic garage, I really don't want to loose all the extra space that a bigger one will inevitably take up. This upright version could well be the answer though!!  :thumbsup:

 

How does it cope with air tools? :unsure:

 

 

This is what concerns me, i like the idea of it taking up less space than my current monster but 10 CFM won't run my high speed grinder properly along with some of my drills. Still its a nice compact size. The Americans run some very nice vertical compressors at very reasonable prices as well. Shame they are not usable here.



#22 firstforward

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Posted 25 May 2013 - 07:11 PM

Surely if the preasure switches were set at different settings then the one that is set at the highest setting would be the only one that would start as that would be the lowest preasure that both tanks would get to. If both tanks are connected then they would always be at the same preasure. Would it not be better to have some sort of electrical delayed timer on one of the compressor motors? Power would go to both of them at the same time when both tanks hit the low preasure setting then one would start followed by x amount of seconds then the second one kick in. I'm presuming you can get an electrical delayed timer switchthingamejig! 

Don't know what you are on about? you connect the two up together on the air side of things, them make sure the pressure switches are slightly different so they come on at different stages.



#23 Daz1968

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Posted 25 May 2013 - 09:08 PM

The idea of different settings on pressure switch is to avoid high current surge being same on both, no problem with them set at different pressure, if not much air being used then the one compressor keeps the tank full, if it can't keep up with demand then pressure drops slightly more and the second one kicks in to keep up with demand. It's a proven method that works. Just make sure both compressors are rated to same pressure.

#24 Guess-Works.com

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Posted 25 May 2013 - 09:10 PM

 

Surely if the preasure switches were set at different settings then the one that is set at the highest setting would be the only one that would start as that would be the lowest preasure that both tanks would get to. If both tanks are connected then they would always be at the same preasure. Would it not be better to have some sort of electrical delayed timer on one of the compressor motors? Power would go to both of them at the same time when both tanks hit the low preasure setting then one would start followed by x amount of seconds then the second one kick in. I'm presuming you can get an electrical delayed timer switchthingamejig! 

Don't know what you are on about? you connect the two up together on the air side of things, them make sure the pressure switches are slightly different so they come on at different stages.

 

 

He's right, if you connect to compressors, the one which is set to come on at the highest pressure will take all the load, so you essentially have one pump with two tanks... the second one will never start because the pressure will never get low enough for the switch to start.



#25 Guess-Works.com

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Posted 25 May 2013 - 09:12 PM

The idea of different settings on pressure switch is to avoid high current surge being same on both, no problem with them set at different pressure, if not much air being used then the one compressor keeps the tank full, if it can't keep up with demand then pressure drops slightly more and the second one kicks in to keep up with demand. It's a proven method that works. Just make sure both compressors are rated to same pressure.

 

Also true, but not really applicable to a domestic situation.



#26 Guess-Works.com

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Posted 25 May 2013 - 09:15 PM



 



 



 


 

I just bought one of these for the garage to power guns, die grinder and small HVLP for spraying blocks etc...  More than up to the job, very portable, small foot print and very keenly priced....

 

https://www.facebook...&type=1

 

 

 

That looks like a really good idea. I've often thought about upgrading to a bigger compressor, but with a small single domestic garage, I really don't want to loose all the extra space that a bigger one will inevitably take up. This upright version could well be the answer though!!  :thumbsup:

 

How does it cope with air tools? :unsure:

 

 

This is what concerns me, i like the idea of it taking up less space than my current monster but 10 CFM won't run my high speed grinder properly along with some of my drills. Still its a nice compact size. The Americans run some very nice vertical compressors at very reasonable prices as well. Shame they are not usable here.

 

 

10cfm is ok for domestic applications, any more than that and you need a 16amp supply which most domestic installations don't, other than for a power shower or cooker.

 

For serious air power I have this in the unit... 15kw / 60cfm

 

Attached File  19112010198_s.jpg   72.8K   9 downloads



#27 sonikk4

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Posted 25 May 2013 - 09:27 PM

 

 

 

 

 

I just bought one of these for the garage to power guns, die grinder and small HVLP for spraying blocks etc...  More than up to the job, very portable, small foot print and very keenly priced....

 

https://www.facebook...&type=1

 

 

 

That looks like a really good idea. I've often thought about upgrading to a bigger compressor, but with a small single domestic garage, I really don't want to loose all the extra space that a bigger one will inevitably take up. This upright version could well be the answer though!!  :thumbsup:

 

How does it cope with air tools? :unsure:

 

 

This is what concerns me, i like the idea of it taking up less space than my current monster but 10 CFM won't run my high speed grinder properly along with some of my drills. Still its a nice compact size. The Americans run some very nice vertical compressors at very reasonable prices as well. Shame they are not usable here.

 

 

10cfm is ok for domestic applications, any more than that and you need a 16amp supply which most domestic installations don't, other than for a power shower or cooker.

 

For serious air power I have this in the unit... 15kw / 60cfm

 

attachicon.gif19112010198_s.jpg

 

 

I have installed a split consumer unit in my garage and will be doing the same in the workshop i share. This is to take into consideration the high start up loading my compressor generates.

 

Its connected via a 16 Amp plug to a 20 Amp mcb type C rated breaker.

 

My next compressor will be much heavier duty to run all of my air tools at their maximum rated speed.



#28 sixtyeight

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Posted 26 May 2013 - 12:04 AM

If you only have a standard consumer rated power point (not sure what that is in the UK? 10A, 13A?) I'd just go for a twin piston 3hp 50-100l 13CFM. Will be fine for spraying. Struggles a little with the die grinder though but patience helps. 

 

One thing to note, all those direct drive compressors shown are so-so. They will be very noisy, and have a relatively short motor life as they are designed to run at high RPM, low displacement as opposed to low RPM high displacement of a belt driven compressor.

 

My mate has a little 30l direct drive compressor and my 3hp twin cylinder is so much quieter!



#29 firstforward

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Posted 26 May 2013 - 05:41 AM

 

 

Surely if the preasure switches were set at different settings then the one that is set at the highest setting would be the only one that would start as that would be the lowest preasure that both tanks would get to. If both tanks are connected then they would always be at the same preasure. Would it not be better to have some sort of electrical delayed timer on one of the compressor motors? Power would go to both of them at the same time when both tanks hit the low preasure setting then one would start followed by x amount of seconds then the second one kick in. I'm presuming you can get an electrical delayed timer switchthingamejig! 

Don't know what you are on about? you connect the two up together on the air side of things, them make sure the pressure switches are slightly different so they come on at different stages.

 

 

He's right, if you connect to compressors, the one which is set to come on at the highest pressure will take all the load, so you essentially have one pump with two tanks... the second one will never start because the pressure will never get low enough for the switch to start.

 

 

Ummmm so why do we need two compressors at all? The reason is because one compressor is unable to supply the quantity of air that is drawn from the equipment used.

 

If you need a supply of say 16CFM and one compressor is rated at 10CMF you are going to run out of air pressure, you could set one compressor to cut in at 110psi and cut out at 140psi as I have, when the first cuts in at 110psi and continues to drop the second can be set to cut in at 105psi to assist the first. As the second cut in later, it shall cut out first ( because you have an over supply of 4CFM ) leaving the first to run until the pressure drops enough for the second to cut in again.

 

I used to own a body repair workshop and the second one only ever kicked in just before the tools became unusable at 70psi, which was on a rear occasion if somebody was trying to fill a tractor tyre with air on the forecourt.

 

The further apart the pressures are set the more work the first compressor shall do in relation to the second.



#30 firstforward

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Posted 26 May 2013 - 05:45 AM

 

 

 

 

 

I just bought one of these for the garage to power guns, die grinder and small HVLP for spraying blocks etc...  More than up to the job, very portable, small foot print and very keenly priced....

 

https://www.facebook...&type=1

 

 

 

That looks like a really good idea. I've often thought about upgrading to a bigger compressor, but with a small single domestic garage, I really don't want to loose all the extra space that a bigger one will inevitably take up. This upright version could well be the answer though!!  :thumbsup:

 

How does it cope with air tools? :unsure:

 

 

This is what concerns me, i like the idea of it taking up less space than my current monster but 10 CFM won't run my high speed grinder properly along with some of my drills. Still its a nice compact size. The Americans run some very nice vertical compressors at very reasonable prices as well. Shame they are not usable here.

 

 

10cfm is ok for domestic applications, any more than that and you need a 16amp supply which most domestic installations don't, other than for a power shower or cooker.

 

For serious air power I have this in the unit... 15kw / 60cfm

 

attachicon.gif19112010198_s.jpg

 

 

I have a 14CFM on a 3hp, no additional wiring needed, but it is at the limit, the size is sold by virtually all manufacturers without any instructions to upgrade your electrical supply.







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