Thank you for purchasing the MICROVAC vacuum gauge. This gauge is far superior to analog gauges presently in use. It provides the full features of a digital gauge in a compact size and low cost.

Thank you for purchasing the MICROVAC vacuum gauge. This gauge is far superior to analog gauges presently in use. It provides the full features of a digital gauge in a compact size and low cost.

Mounting - The MICROVAC should be mounted in a stem down (display up) position within 45 degrees of vertical. It's connection is one-eighth inch male pipe thread. If it is to be mounted directly on a vacuum pump, it is desirable that the connection to the pump have at least two 90 degree elbows. If this is not done, back streaming (that is, oil vapors returning from the pump) may shorten the gauge tube life. An optical baffle is also available. With appropriate fittings a pressure gauge "siphon" such as McMaster-Carr 4031K11 may be used.

The MICROVAC should be tightened using a 7/16" wrench on the flats of the gauge tube. Do not use the body of the gauge as a wrench!

After the gauge is in place, connect the AC adapter. Atmospheric pressure is 760 Torr or 760,000 Microns. The gauge will initially read off-scale 1-. It's actual range is 0-1999 microns; the preferred values for good vacuum evacuation.

If the installed position of the gauge and readout is not convenient, an extension cable is available from HyVac Products, Inc. that enables remote mounting of the display.

The MICROVAC gauge and tube are calibrated together. It is best the recalibration be done by HyVac Products, Inc. If field calibration is desired, proceed as follows:

(a) Operate the unit at the lowest possible pressure level (1 micron with a diffusion pump, approximately 7-10 microns from a belt-driven two-stage mechanical pump, approximately 10-15 microns from a direct-driven, two-stage mechanical pump, approximately 30-40 microns from a direct-driven, single-stage mechanical pump).

(b) The zero adjustment is available on the left side of the gauge.

(c) Operate the unit at a value of approximately 1800 microns; adjust the high end with the adjustment available on the right side of the unit.

Factory recalibration price is $60.00

Replacement vacuum gauge tubes are available from HyVac Products, Inc. for

If the gauge is to be used in a neon sign processing facility, it must be installed with a stopcock or a solenoid valve to protect it from exposure to the system and possible damage during high voltage bombarding.

For repair or recalibration, return gauges to: HyVac Products, Inc,