Company Profile

Alicat Mass Flow Controllers & Alicat Flow Meters: High-Speed Scientific Gas Flow Instrumentation

Quick Answer: Alicat mass flow controllers and Alicat flow meters are fast response gas flow devices for laboratory, analytical, and OEM gas control systems. They provide direct mass flow readings for many gases without separate pressure and temperature transmitters. Silver Automation Instruments supplies these high speed scientific gas flow instruments with application support, calibration guidance, and process instrument packages for customers in Southeast Asia, Australia, New Zealand, the Middle East, Africa, and Latin America.

We hear the same request from many engineers and procurement teams. They need a gas flow meter or controller that reacts faster than an older thermal bypass meter. They need accuracy at low setpoints. They also need a supplier who can quote the complete package without sending twenty emails. This page covers the Alicat device range we commonly quote and how to specify one quickly.

What Makes Alicat Devices Different for Gas Flow Control

Alicat mass flow controllers use a laminar flow element to measure differential pressure. The meter electronics convert that pressure drop into mass flow using live temperature and pressure data. This is why many Alicat devices can read mass flow directly and output signals such as 4-20 mA, 0-5 VDC, RS-232, or RS-485 Modbus RTU.

The practical benefit is response time. Many Alicat controllers settle a flow step in 10 to 30 milliseconds. Some high speed units get closer to 5 milliseconds. In gas mixing, leak testing, and analytical sample lines, that speed matters because the loop can correct flow before the analyzer or reactor sees the upset. Most engineers skip this part until they compare a standard controller on a flow bench and see the difference.

Common Applications We See on Customer Sites

We have quoted Alicat gas flow meters for gas chromatography and mass spectrometry. A research institute in Selangor ordered several MC series controllers for calibration gas blending on a test bench. Each controller handled a different range from 0 to 10 SCCM up to 0 to 50 SLPM. The lab used 1/4 inch compression fittings and RS-232 signals for a Python based data logger.

In the Middle East, a gas blending skid builder needed fast air and nitrogen control for a continuous emissions monitoring system test stand. They chose Alicat MC series controllers with 4-20 mA and Modbus RTU. The main requirements were response time under 50 ms and repeatability better than 0.5 percent of reading.

Other common applications include plasma spray gas feed, bioreactor gas control, fuel cell test stands, catalyst screening, and leak testing. In these systems, Alicat flow meters are often used as the reference meter or the final control device before the gas enters the process.

Key Specifications Engineers Ask for Before They Buy

Most engineers ask about accuracy, repeatability, turndown, and wetted materials. A standard Alicat mass flow meter often has accuracy around plus or minus 0.8 percent of reading plus 0.2 percent of full scale. High precision options can bring that to plus or minus 0.4 percent of reading plus 0.2 percent of full scale. Repeatability is often 0.2 percent of full scale or better.

Flow range is not one size fits all. Small analytical flows can start at 0 to 0.5 SCCM. Larger process flows can reach 0 to 4000 SLPM on some industrial devices. Turndown ratio is often 200 to 1, which means a device can control down to 0.5 percent of full scale. This turndown ratio is helpful when you need one mass flow controller to cover both purge flow and small sample flow.

For a gas type that changes or a gas mixture with variable density, the CODA series Coriolis controllers are a better fit. They measure mass directly and do not rely on ideal gas property tables. We have seen thi