Digital Display Vacuum Transmitter with Diffusion Silicon Sensor

1. Why You Need It

Vacuum processes — packaging, drying, degassing, suction lines — require accurate, responsive measurement of negative pressure, and operators benefit from seeing it locally. This vacuum transmitter uses a diffusion silicon sensor with a digital display, delivering a fast <10 ms response and HART communication. It provides reliable, readable vacuum measurement for process lines where a stable negative-pressure signal keeps the process in control and product quality consistent.

2. Working Principle

A diffusion silicon sensing element detects the pressure difference across a diaphragm, with the reference side configured for vacuum or negative pressure measurement. The deflection is converted to a 4-20 mA signal (with 0-5 V, 0-10 V and 0-20 mA options), and the integrated digital display shows the vacuum level locally. HART communication adds remote configuration and diagnostics over the same loop.

3. Key Advantages

• Diffusion silicon sensor
• Integrated digital display
• 4-20 mA / 0-5 V / 0-10 V / 0-20 mA
• HART communication
• <10 ms response time
• Suitable for vacuum / negative pressure
• Air, water and liquid media
• 1/4 NPT thread connection
• 0.5% FS typical stability
• Wide configurable range

Common Pain Points & Solutions

Application Cases

Technical Specifications

FAQ

Q: What is a vacuum transmitter?

A vacuum transmitter measures pressures below atmospheric (negative pressure) and converts them into a standard output signal such as 4-20 mA. It is used to monitor and control vacuum in processes like packaging, drying, degassing and pneumatic systems. The diffusion silicon sensor provides stable, responsive measurement of negative pressure.

Q: What sensor technology does it use?

It uses a diffusion silicon sensor, a type of piezoresistive sensor where strain gauges are diffused directly into a silicon diaphragm. This technology offers high sensitivity, fast response and good stability, making it well-suited to vacuum and low-pressure measurement.

Q: Does it have a local display?

Yes, it has an integrated digital display that shows the vacuum level locally. This lets operators read the negative pressure at the measurement point without a separate indicator, which is convenient for commissioning, troubleshooting and routine process checks.

Q: What output signals are available?

The transmitter offers 4-20 mA, 0-5 V, 0-10 V and 0-20 mA outputs, plus HART communication. The 4-20 mA loop is standard for process control, the voltage outputs suit data acquisition systems, and HART provides remote configuration and diagnostics.

Q: How fast is the response?

The response time is under 10 ms, so the transmitter can track rapid vacuum changes in dynamic processes. This fast response is important for applications like vacuum packaging and drying, where the vacuum level changes quickly and the control system needs current data.

Q: What media can it measure?

It measures air, water and liquid media. The diffusion silicon sensor is compatible with clean, non-corrosive media; for aggressive or corrosive media, the wetted material compatibility should be verified before selection.

Q: What is the process connection?

The process connection is 1/4 NPT thread, a standard fitting for vacuum and pneumatic lines. The threaded connection allows straightforward installation into the vacuum manifold or vessel.

Q: How does it differ from a gauge pressure transmitter?

A gauge pressure transmitter measures pressure relative to ambient atmosphere and is typically used for positive pressures. A vacuum transmitter is configured to measure pressures below atmospheric (negative gauge pressure). The diffusion silicon sensor can be ranged for vacuum or compound (positive and negative) measurement.

Q: What is the stability?

The stability is typically 0.5% FS (with a maximum of 1% FS), providing reliable long-term measurement for process vacuum applications. This stability ensures the vacuum reading remains accurate between calibrations.

Q: Where is it used?

It is used in vacuum packaging, vacuum drying, material degassing and pneumatic suction systems. Anywhere a stable, responsive, locally readable vacuum measurement is needed for process control, the digital display vacuum transmitter provides the required performance.