Vacuum Measurement & Control
Filters
Vacuum gauges and controllers
Vacuum measurement and control instruments fall into two groups: gauges that measure pressure accurately, and controllers that regulate pressure automatically. Because a thermocouple vacuum gauge measures pressure while a vacuum controller can actively hold a set pressure, understanding the difference is the key to choosing the right instrument.
Choosing an instrument+
Decide first whether you need a gauge (measurement only), a controller (automatic pressure control), or a combined gauge-controller.
For a gauge, select by the pressure range you need to read and the sensor type suited to that range, and confirm the connection matches your system.
For a controller, distinguish measurement-only gauges from control-capable devices, check compatibility and connection types, and confirm calibration, accuracy and availability. Verify wiring, setpoints and relay functions against the specification before purchase.
Gauges vs controllers+
Vacuum gauges for measurement
Vacuum gauges report the pressure in a system and are available in digital and analog forms across different measurement ranges and sensor types. Thermocouple vacuum gauges are a common type for the rough-to-medium vacuum range, inferring pressure from the heat loss of a heated element. Welch offers the 1520 vacuum gauge and the 1526 thermocouple gauge; select by the pressure range you need to read and the sensor type suited to that range, and confirm the connection matches your system.
Vacuum controllers for automatic pressure control
Vacuum controllers do more than measure: they regulate pressure automatically, often using setpoints, relays and valves to hold a target vacuum or follow a program. This supports reproducible processes such as controlled evaporation and distillation. When comparing, distinguish measurement-only gauges from control-capable devices, check compatibility and connection types, and confirm calibration, accuracy and availability. Welch offers the VCB 601 vacuum controller and the 1640A vacuum controller; verify wiring, setpoints and relay functions against the specification before purchase.
Related categories
FAQs+
What is a thermocouple vacuum gauge?
It is a gauge that measures vacuum in the rough-to-medium range by sensing the heat loss from a heated element, which changes with gas pressure. It is a common, robust gauge type for many vacuum systems.
What is a vacuum gauge controller?
It is a device that combines pressure measurement with control functions, displaying the vacuum level and using setpoints or relays to trigger actions or regulate pressure.
What is a vacuum controller used for?
A vacuum controller regulates the pressure in a system automatically, holding a target vacuum or following a programd profile, which supports reproducible processes and can reduce operator intervention.
What is a vacuum pressure controller?
It is another term for a device that actively controls the vacuum level in a system, typically by adjusting a valve or the pump against a measured pressure and a setpoint.
Can a vacuum controller regulate pressure automatically?
Yes. That is its purpose: it measures pressure and adjusts a valve or pump to hold the set level automatically, unlike a gauge, which only measures.
How do you choose a vacuum gauge controller?
Match the measurement range and sensor type to your system, confirm the control functions you need (setpoints, relays, automation), and check compatibility and connection types. Verify calibration and accuracy for your application.
What features should you look for when buying a vacuum gauge?
Consider the pressure range and sensor type, digital or analog readout, accuracy and calibration, connection type and compatibility with your system, and whether you also need control functions.