Vacuum Gauge Vibration

It could be any combination of:

• The design of the gauge
• The location of the gauge within the process pipework.
• The vibration caused by the exhauster.
• The vibration caused by something else.
• Some other cause.

As the forum cannot see the installation, any further commentary is pure hypothesis.

Sounds like air turbulence...I would look for obstructions in the tube leading to the gauge, or placement of the feeding tube angle, or location, or air leak in the connections or tube someplace....when you say the gauge is vibrating, are you saying the needle or the entire gauge? I assumed the needle....

yes it is the needle that is vibrating and according to the spec the supply of current to the drive is constant which means the output of vacuum has to be constant too, so the needle has to be stable at all times?

Anyone who has synchronised carburetors will know exactly what you're talking about. Sometimes a needle valve works well as a snubber.

We see the same thing happen to the barometer on the flight controller of a quad-copter. The solution is a snubber over the hole. In this case the snubber is a piece of open cell foam rubber. Then the barometer will not see the pulses from the props. The snubber slows the reaction times and so smoothes out the reading to a more ambient/average reading.