Review on Supco Digital Vacuum Gauge 12000 by Will Schimmel

Bought the SUPCO VG64 (small LCD version) cheap due to generally poor reviews. Surprise! it works pretty well. That's what I mean by "pretty good". Using a 50 micron vacuum pump connected to a good and dry vacuum hose connected to both the VG64 and an established micrometer, the reference gauge reached the expected 50 microns. VG64 showed 31 microns. When pumping, the sensors typically agreed to within 50 microns. As advertised, the VG64 has a higher refresh rate. Other results were obtained with a cheap 150 micron single stage pump. Using the same test fixture, the reference probe performed as expected and settled at 180 microns. The VG64 had some stable reading issues. I suspect this is due to pressure fluctuations in a cheap pump that would likely be dampened by normal system evacuation. The gauges on both gauges were cleaned before testing and the vacuum pumps had fresh oil. Next, since the VG64 seems to be known for internal leaks, I pulled the vacuum to 200 microns, closed the hose and shut off the vacuum pump. After weaning, VG64 remained stable for one hour. After standing overnight it still reads 440 microns. On the other hand, the documentation is bad. SUPCO has at least once changed the design to a larger LCD version without making a big deal out of the change, such as: B. VG64 "b", "2.0" etc. The lack of an obvious support page for older products does not inspire confidence. I had to find instructions elsewhere for this earlier model. So what can be said about SUPCO VG64? It makes a robust and well-made impression. It works decently well, although I suspect the accuracy is a bit off. It twitched when hooked up to an inferior single-stage vacuum pump via a short vacuum hose, but it wasn't normally used that way. This is accurate enough to measure the 100-500 microns recommended for refrigeration applications. Seems to be a good secondary or backup sensor. Would I buy anything else from SUPCO? Probably no.