Switching on compressor

[Pinky]

Why can't you switch your compressor on and of with the mains switch

Cheers pink

 

[ford34/2]

Tell us more,--- what`s the compressor switch gear ?? whats the compressor, small toy or large industrial?? single phase 3 phase??

Stan

 

[rtbcomp]

On 99% of the compressors in general use there is a device in the pressure switch called an unloader valve. Its function is to empty the pipe between the pump and the tank (the delivery pipe) when the compressor switches off at the set pressure; this gives the characteristic hiss.

If the delivery pipe is pressurised when the pump starts the motor will most likely stall.

If you do switch off at the mains you must set the pressure switch to off, wait until the hissing has stopped, switch the mains on and then switch on at the pressure switch. (You can reverse the last two steps).

If the mains fails whilst the compressor is running you must switch off at the pressure switch to release the pressure in the delivery pipe before the mains comes back on. It's a good idea to run a compressor through a no-volts release device.

 

[Pinky]

Thanks for the reply's
Will it damage the compressor if you switch it of at the mains ,
My problem is getting to the switch on the compressor
I have been using the mains switch
With no problems
However they don't stick a warning on it for nothing

Pink

 

[rtbcomp]

It could cause damage. If the compressor has been switched off for a while the delivery pipe may empty due to leakage so you may get away with it.

 

[AndyStobbs]

Don't switch it off mid flow and you'll be fine.

 

[brightspark]

u can switch your compressor on and off by the main switch as long as u make sure the tank is empty next time u go to start it

 

[rtbcomp]

The tank itself doesn't need to be empty, just the delivery pipe.

If you do switch it off mid flow, just switch the pressure switch to 'off' before attempting to restart it.

 

[the snooper]

you could always fit a solenoid valve to vent the delivery pipe when the power is cut

 

[Bill Edwards]

Let it build up air fully and shut itself off, then you can switch off at the mains without damage. Don't switch it off while it is still running unless you will then switch it off at the proper switch.

Alternatively I suppose you could tap into the pipe that goes to the existing unloader valve and fit a valve that you then use to manually release the air in the delivery pipe before switching it on again.

 

[the snooper]

Let it build up air fully and shut itself off, then you can switch off at the mains without damage. Don't switch it off while it is still running unless you will then switch it off at the proper switch.

Alternatively I suppose you could tap into the pipe that goes to the existing unloader valve and fit a valve that you then use to manually release the air in the delivery pipe before switching it on again.

but he has a problem reaching the switch so would be the same for the valve, and you wouldn't want to extend the delivery hence the reason I suggested a solenoid valve because as soon as the power is cut automatically or via the mains switch it would vent the delivery pipe

 

[Bill Edwards]

I was thinking that if he tapped into the little pipe that goes to the unloader valve - often just a small (1/8"?) nylon type of thing - with say a T piece he could make it as long as needed then fit a simple ball valve or better yet, a pull to drain type valve near where the mains switch is located. Then a quick pull/turn whatever to vent the air and switch it on.

Your method would be fine but requires wiring which some people shy away from. Can you easily get a solenoid that's closed when the power is on, rather than the open as is commonly found?

 

[the snooper]

I was thinking that if he tapped into the little pipe that goes to the unloader valve - often just a small (1/8"?) nylon type of thing - with say a T piece he could make it as long as needed then fit a simple ball valve or better yet, a pull to drain type valve near where the mains switch is located. Then a quick pull/turn whatever to vent the air and switch it on.

Your method would be fine but requires wiring which some people shy away from. Can you easily get a solenoid that's closed when the power is on, rather than the open as is commonly found?

yeah that could work ok
not sure ? on the solenoid will have a look
edit: yes they are available

 

[brightspark]

move the main switch job done

 

[Pinky]

Thank you for the replys,
What damage could you cause not using the proper switch ?

Pink

 

[optima21]

none as long as you turn it off at the mains after the compressor has stopped due to reaching working pressure. if you turn it off at the mains when its still running, the pressure in the pipes causes the motor to stall when it starts up again (or thats how mine have worked). Ive just switched mine off at the mains plug for the last 15 years without issues.

 

[Bill Edwards]

Overload the motor!

 

[pedrobedro]

Or the bearings in the pump if you do it too often.

 

[dannyp]

i've switch mine off at the plug since i've had it never had a problem to much effort to wander about outside in the dark tripping over it to flick the switch on it

 

[Bill Edwards]

You may get away with it just fine when your compressor is not in perfect condition and it has enough time for the air to leak out of the delivery pipe.