Vacuum gauges?

Hi all, was wondering which vacuum gauges are being used? Any one try any digital ones? Can’t seem to find a good source for them in dig. or analog. Thanks Al

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Hi Al,
I have a couple of these digital vacuum gauges
http://www.ebay.com/itm/Digital-Manometer-Differential-Air-Pressure-Meter-Gauge-/120658272340
They read very accurate and they go up to 55 inches H2O. The downside is they are not easy to mount and they automatically shut off after a while just before you want to look at them.
Also they are up in price now from when I bought them.

Good morning brother Al

I can’t help much with any of the digital gauges but the below gauge is what I use ( old school )

http://www.zoro.com/i/G0813531/

Don; thanks this may be what I am looking for. I am building a slide in unit, and these would be more portable. When they turn off can you push button to turn it on Quickly? What batt. do they use? couldn’t read it on the description. Wayne; thanks, I will use these also on the unit as a back up system. Thanks again Al

Yes Al they turn back on quickly and it is 9 volt batt.

Hi Don,
Ever wonder if anybody looks back over your photos? I just looked at yours and like the sheet metal roll former. I can’t afford an anvil yet, but I could build something like this for metal forming,
Pepe

Would these carburetor synchronizer gauges for motor cycles work for a gasifier?

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@r_wesseling they will work, but the movement of the needle will be confined to a really narrow slice of the overall dial (the sensitivity won’t be very good for typical gasifier vacuum measurement). Ideally, we want something that will give easy-to-read sensitive measurements with a lot of travel on the gauge for the indicator.

Those carb sync gauges use mm Hg as a scale for vacuum - totally appropriate for a lot of things, certainly. Most in the states use gauges calibrated for the “water column” scale AKA inches of H2O AKA in.H2O AKA inches WC. Not necessarily because of any metric vs imperial debate, but because water is much less dense than mercury, meaning that small changes in negative pressure cause comparatively larger changes in measured value.

For reference, the pressures in play for most gasifiers : 9 mm hg / 5 inches h2o (0.1 psi / 1100 pascal, etc etc) at the low end up to around 60 inches H2O / 110 mm hg (etc).

@r_wesseling see also the ‘gauges’ topic in premium.

Here’s one example:


You can see from the dial that the “inch water column” scale uses only about 1/7 of the range that a 0-30" Hg (Mercury) gauge does. And the price goes up about that much, too.
But hey, it’s a one time investment in not having to guess what is going on in there.

Pete Stanaitis

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