normspanners
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Tried this today it's been in the back of my mind to try for a while,
what I did was to put the pressure control switch in the line to the main circuit but plumbed in with a 3/4 tee with a 3/8 leg on the tee, I used 3/8 m/m hex nipple with a 10mm bolt taped into it so it was tight and the end of the bolt is the the main air flow then drilled the centre of the bolt right through with a 3mm drill and then cut the free end of the bolt at 45 deg angle to form a venturi, I marked the hex nipple as to the correct orientation, screwed the nipple in to the tee, then the switch onto the nipple. The shut off valve is obviously after the tee on its way to the workshop main ring to ensure the pressure switch always sees tank pressure unless air is being drawn off.
the idea of this is so that when a large amount of air is drawn off the main, a greater pressure drop will be seen at the switch due to the venturi and hopefully switch the compressor on earlier. That then helps the compressor keep up with demand better, so that it starts pumping as soon as a large amount of air is required.
I have the compressor set to cut out at about 165 and cut in at 150 the tank is roughly 300lts and takes about 10 seconds to refill and cutout.
it is difficulty to test the theory exactly, but it seems to work.
During tests today the pressure in the tank did not drop below 150 running two guns and other stuff.
what I did was to put the pressure control switch in the line to the main circuit but plumbed in with a 3/4 tee with a 3/8 leg on the tee, I used 3/8 m/m hex nipple with a 10mm bolt taped into it so it was tight and the end of the bolt is the the main air flow then drilled the centre of the bolt right through with a 3mm drill and then cut the free end of the bolt at 45 deg angle to form a venturi, I marked the hex nipple as to the correct orientation, screwed the nipple in to the tee, then the switch onto the nipple. The shut off valve is obviously after the tee on its way to the workshop main ring to ensure the pressure switch always sees tank pressure unless air is being drawn off.
the idea of this is so that when a large amount of air is drawn off the main, a greater pressure drop will be seen at the switch due to the venturi and hopefully switch the compressor on earlier. That then helps the compressor keep up with demand better, so that it starts pumping as soon as a large amount of air is required.
I have the compressor set to cut out at about 165 and cut in at 150 the tank is roughly 300lts and takes about 10 seconds to refill and cutout.
it is difficulty to test the theory exactly, but it seems to work.
During tests today the pressure in the tank did not drop below 150 running two guns and other stuff.
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