
I've got two compressors, i'd like to run them in parrallel to give me a 3.5hp, 100l, compressor (ok, i accept it will have losses so it
will be more like 3hp).
One compressor has just one output and the other has a restricted output and a "what ever pressure its got, you get" output.
A mate in the office says that if i just link the first compressor into the unrestricted connection on the second compressor i'll end up with two
bust compressors. His argument is that the safety valve / on/off switch can't take pressure greater than whats in the compressor.
Does anyone know if this is true and therefore i need a check valve or if he's talking rubbish.
Sounds like rubbish to me, they will both pump to their limits so the one with a cut off will stop when the pressure is reached.
The safety switch will take loads more pressure, before this goes, the emergency vent will be puffing out air long before this can happen.
The only problem I can see is if the unrestricted one cannot pump as high compressor with a cut off and the overload of pressure will cause it to
stall burning out the motor.
[Edited on 28/10/08 by mark chandler]
quote:
His argument is that the safety valve / on/off switch can't take pressure greater than whats in the compressor.
But they're supposed to switch from the tank going to the switch, not from the outside world pushing from the other direction - this is what he
thought would brake them.
(Well at least thats how i remember it).
They're both rated to about the same psi so they should both stop about the same time.
Edit- also if i do need them, where is the cheapest place to get them?
[Edited on 28/10/08 by MikeR]
should be ok as long as both air receivers are rated at the same pressure .m.
why not come out of both with a line and connect the two lines with a y piece then ideally run on line throuater seperator and adjustable gauge thats what i do.
How long have you been doing this for?
Have you had any problems?
What compressors do you use? (please say ones from Aldi)
Was I pixxed when i wrote that or all thumbs, note to self check spelling. Shouls have said run the one line through a water seperator and gauge
If you connect them after their respective pressure switches it should not be a problem, if you set one switch a few psi above the other you may find that the system need only run the one compressor until it can't cope with the demand then the other should cut in. Two compressor will not increase pressure just supply volume.
Can't you run them though a common cutoff switch?
ATB
Simon
I run 2 of the cheaper screwfix ones in parallel. They both got two outlets exactly as you describe. I've just got a short length of hose
coupled between the two unrestricted outlets. I've had it like that for over a year now with no problems.
As mentioned though you do need to check that they're both rated for the same pressure or you could in theory blow one up - but the safety valve
would have to be broken to let this happen as well! In my experience it works really well. I can run die-grinders almost continually and paint
spray/impact gun/socket driver + drill etc readily with no problems....Oli.
well as i only have one un-restricted outlet, i'll try running the smaller 1.5hp compressor into that and hope nothing goes pop.
You can get a compressor that runs two single phase motors & pumps as individal units on the one tank, it's to allow a capacity beyond what
is possible with a single pump on a single phase supply. I dont know how they're switched, it'd seem logical to have them starting slighly
staggered to avoid the high starting load which is the reason for running two smaller ones rather than one large in the first place.
What you're planning is a DIY version, if they can do it then it's surely possible for you?
i used an aldi one and a clark one, linked both through a Y on the output, no valves or owt. Worked fine.
Numpty question - but how do you tell the difference between the restricted and unrestricted outlets?j
Like mentioned above, you can do this either way: connect the tanks via the outlet, or connect the hoses. As long as the ratings are more or less the
same (say around 8 bar).
Be careful not to blow out the fuse of your garage power supply. 3,5HP = 2610W @ 230V = 11,3 A, with peak current during startup.
the cunning plan for the fuse is to do what i do when welding full power - take a feed from the cooker socket in the house
Did you know that you can draw more than 13 amps through a 13amp socket and cable?
I won't tell you how much you can draw so you're responsible for your own demise but i occasionally push the envelop or what ever other
phrase you want to use 
quote:
Originally posted by austin man
why not come out of both with a line and connect the two lines with a y piece then
quote:
Originally posted by MikeR
the cunning plan for the fuse is to do what i do when welding full power - take a feed from the cooker socket in the house![]()
Did you know that you can draw more than 13 amps through a 13amp socket and cable?
I won't tell you how much you can draw so you're responsible for your own demise but i occasionally push the envelop or what ever other phrase you want to use![]()