Re: Is there any reason not to charge a compressor upto 8bar?



On 7 Feb 2006 09:02:32 -0800, jon.p.weaver@xxxxxxxxxxxxx wrote:

I have just got my new 100 Litre (3hp) upright compressor and notice
that its only charging to 7bar.

I wondered if the gauge was inaccurate, but its got 2 and both read
almost exactly the same.. As I final test, I have a engine compression
tester which I connect and indeed its at around 7 bar.

Is there any reason why I should not adjust the 'cut off' so that it
fills to 8bar? If it has 8 bar in the tank as opposed to 7, then I
assume am going to get more air out (100 litres more), but its
obviously going to take longer to charge and will put extra pressure on
the tank and fittings.

Has it been set to 7 intentionally, or is it normal to 'fine tune' it
during its first few used?

If this is a single-stage one cylinder compressor, 7 BAR / ~100 PSI
is a reasonable setting and will run most any tool you have. You can
go slightly higher IF the pump and motor combination can handle the
extra load, and the tank and plumbing are rated for it.

The manufacturer deliberately sets the pressure switch in the
factory at a "safe" level slightly lower than the maximum the pump and
motor assembly can attain, so they don't have to deal with failures
brought on by excessive running time (as it labors to get that last
pound) or motors overheating.

All pumps have a maximum pressure where you don't get any useful
output, and for a small single stage, that's about it. If the motor
doesn't overload and stall, the pump output drops off to nothing.

And they set the switch with a reasonable differential point of
between 15 - 30 PSI (1 - 2 BAR) so it isn't starting and stopping
constantly - you can damage the motor by starting it more than 6 to 10
times an hour, the start capacitor or winding can overheat.

If you need higher pressures on a regular basis, you have to go to a
two-stage pump. They are good for 150 - 175 PSI.

--<< Bruce >>--
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.
.



Relevant Pages

  • Re: water supply problem
    ... drilled well, the pump is ... more instances of losing water pressure. ... Take a look at your pressure tank. ...
    (misc.rural)
  • Re: 2005 Honda Civic LX gas mileage
    ... >> thus reducing the absolute air pressure in the tank. ... Thus the pressure at the pump inlet will ...
    (rec.autos.makers.honda)
  • Re: Water Storage Tank - Plumbing the Pump & Pressure Tank
    ... If I always have the 2500 gallons in it ... So I think that should be sufficient enough to get the water to the pump ... So the Hydrant is connected to the bottom on the Tank to ... increase the pressure above the incoming pressure. ...
    (alt.home.repair)
  • Re: Well- House Water Volume
    ... Even in hy older city houses I replaced all 1/2 inch copper pipe with 3/4 ... what needs to be done to increase water volume so that the pressure in showr ... steps to look at tank). ... The pump really doesn't have much to do with volume unless it is ...
    (alt.home.repair)
  • Re: 2005 Honda Civic LX gas mileage
    ... >>> thus reducing the absolute air pressure in the tank. ... You seemed to be implying this reduced the pump work. ...
    (rec.autos.makers.honda)