User Menu

Help Choosing a Gauge

We write this to help our customers determine what type of vacuum gauge and what kind of vacuum sensor they need.  Below is a quick overview of the terminology often used when dealing with vacuum instrumentation

Physics of Vacuum gauge sensors and manometers

If you haven’t been in the vacuum industry for many years, you might want to consider browsing wikipedia or another source on some of the basic types of pressure and vacuum measurement .  Digivac uses a variety of it’s own sensors, as well as sensors from a third party.  Digivac has perfected the use of thermocouple vacuum gauge tubes, which is similar to a pirani gauge in theory.

Terminology used by Vacuum vendors

The most important thing that any vendor can offer you is the ability to solve your vacuum measurement or process control challenge in a quick, efficient and cost effective manner. Therefore, it’s important to understand industry standard terminology.

Vacuum Gauge

A Vacuum gauge is a device that measures the pressure, or that pressure below atmosphere.  Digivac uses this term to refer to the product that you buy that includes all of the components needed to measure vacuum.  This includes a vacuum gauge controller, the thermocouple vacuum gauge tube.  Sometimes vendors may refer to the transducer (such is the case with some capacitance manometer vendors) as a “vacuum gauge.”

Vacuum Gauge Controller

A vacuum gauge controller is the device that translates the vacuum sender, the vacuum transducer, the thermoucouple vacuum gauge tube or other tranducer to a meaningful output.  For example, Digivac makes Vacuum gauge controllers for capacitance manometers and other types of vacuum sensing devices.

Thermocouple Vacuum Gauge Tube

A thermocouple vacuum gauge tube is a tranducer that senses vacuum by leveraging the principal of seeing how a wire changes temperature as vacuum is changed.  Common vendors of  thermocouple gauge tubes are Varian, Fredericks, Hastings and VGT, to name a few.  This inexpensive vacuum sensing technology enables Digivac to provide significant value to their vacuum instrumentation.

Vacuum Controller

A vacuum level controller is a device that holds the vacuum of a system at a particular vacuum set point.  Often this is achieved manually by a person connecting a vacuum gauge to a system, and manually cracking a vacuum valve open to achieve the desired vacuum.  A vacuum level controller device like the Digivac Model 450 can achieve this in the Torr range with far less human intervention.