By comparing the 0-1,000 micron vacuum gauge in the top picture to the 0-100 micron vacuum gauge in the bottom picture the accuracy potential of each gauge can easily be seen.

On the 0-1,000 gauge the range between 0 and 10 microns is a relatively small percentage of the scale compared to the 0-100 gauge, where the 0-10 microns range is approximately half of the scale.

Measuring a vacuum of less than 5 microns (the upper limit for general neon tube processing) can be accomplished with either gauge. And while the 0-1,000 gauge is useful for indicating approximate measurements in the low micron range and is useful for most neon work and a superior alternative to inexpensive digital gauges, it can be seen that the 0-100 gauge will provide a more precise reading in the low micron range. Therefore, for critical work where an accurate vacuum reading of less than 1 micron is necessary, or where the processing technician desires superior results, the 0-100 micron gauge should be used.

As with all electrical and mechanical instruments, each gauge has an accuracy variance. The 0-1,000 gauge has an accuracy of ± 2% AMD (Angular Meter Deflection), which in this case is ± 1.5 µ* at a reading of 5 µ. The 0-100 gauge has an accuracy of ± 1% AMD, which equates to ± .2 µ at a reading of 1 µ.

* µ = micron