Product selection guide

The selection guides below will give you a rough idea of which product lines will best serve your application.

Product Selection Guide for Flow Measurement and Control

What is your medium? Are you flowing a gas or liquid?

• If liquid, you will need an L-Series meter, available in flow rates from 0-0.5 ccm to 0-10 lpm, or an LC-Series controller, available in flow rates from 0-5 ccm to 0-5 lpm.
• If you are flowing a gas, which one? The Gas Select™ table below lists all of the selectable mixed and pure gas calibrations that are included in each Alicat mass flow instrument for gases. If your gas is one of the corrosive gases, you will need an S-Series mass flow instrument as we proceed.

Gas Select™ 5.0 Gas List for Alicat Mass Flow Meters and Controllers

All Alicat Scientific mass flow meters and mass flow controllers come standard with NIST Ref Prop 9 gas properties data for up to 130 preloaded gas calibrations. Users may switch between selected gases on the fly without any need for recalibration of the mass flow meter or controller. All Gas Select™ calibrations retain the instrument’s specified NIST-traceable calibration accuracy. (See individual specifications sheets for details.)

Do you want to measure, control or calibrate your gas flow?

• If measuring only, you will need an M-Series mass flow meter, available in full-scale ranges from 0-0.5 sccm to 0-4000 slpm, or other equivalent engineering units. You can also choose an MB-Series portable mass flow meter with an integrated rechargeable battery for field use without wires. If you require low pressure drop (less than 1 psi), then be sure to look at our Whisper Series (MW), with pressure drops as low as 0.06 psi (4 mbar) at full scale. (Note that the maximum inlet pressure for the Whisper Series is 45 psig, compared with 145 psig for our standard M Series.)
• If controlling, you will need an MC-Series mass flow controller, available in full-scale ranges from 0-0.5 sccm to 0-3000 slpm, or other equivalent engineering units. If your application requires flowing gas into a process in one direction and then out in the reverse direction, you may find that our MCD-Series bidirectional mass flow controllers can simplify your equipment needs. If you require low pressure drop (less than 1 psi), then be sure to look at our Whisper Series (MCW/MCDW), with pressure drops as low as 0.06 psi (4 mbar) at full scale. (Note that the maximum inlet pressure for the Whisper Series is 45 psig, compared with 145 psig for our standard M Series.)
• If controlling flows into vacuum, you will need our MCV-Series mass flow controller for vacuum, which includes an integrated pneumatic shut-off valve to prevent vacuum chamber contamination when you have a zero setpoint. This series is available in flow ranges from 0-0.5 sccm to 0-20 slpm.
• If you are calibrating, you easiest solution will be an MB-Series portable flow calibrator with an integrated rechargeable battery for ease of use in the field. Portable calibrators are available in full-scale ranges from 0-0.5 sccm to 0-4000 slpm, or other equivalent engineering units. For calibration of flow ranges wider than a 200:1 turndown (e.g., 1-200 sccm), choose Alicat’s PCU-Series portable calibration unit, a field-portable unit that integrates 3 portable flow calibrators of differing ranges for a combined turndown range of up to 1,000,000:1.
• If you are calibrating volumetric flows, or otherwise require low pressure drop (less than 1 psi), then be sure to look at our Whisper Series (MWB or PCUW), with pressure drops as low as 0.06 psi (4 mbar) at full scale. (Note that the maximum inlet pressure for the Whisper Series is 45 psig, compared with 145 psig for our standard M Series.)

Product Selection Guide for Pressure Measurement and Control

Does your application depend upon absolute, gauge or differential pressure?

• To reference your application to atmospheric pressure, you will want to choose a pressure instrument with a gauge pressure range, normally indicated by “PSIG” in Alicat’s part numbering system. Alicat gauge pressure instruments are generally available in ranges from 0-2 inH2O(G) to 0-500 psi(G), or other equivalent engineering units. Negative ranges are also available to -15 psi(G).
• To reference your application to vacuum, you will want to choose a pressure instrument with an absolute pressure range, normally indicated by “PSIA” in Alicat’s part numbering system. Alicat absolute pressure instruments are generally available in ranges from 0-30 psi(A) to 0-500 psi(G), or other equivalent engineering units. Reference to absolute pressure is an excellent way to stabilize the effects of stormy atmospheric conditions, in which barometric pressures can change rapidly.
• If your application requires measurement of the difference between two pressures, you will want to choose a pressure instrument with a differential pressure range, normally indicated by “PSID” in Alicat’s part numbering system. These instruments include two dead-ended pressure ports that lead to opposite sides of a differential pressure sensor. Alicat differential pressure instruments are generally available in ranges from 0-2 inH2O(D) to 0-150 psi(D), or other equivalent engineering units.

Do you want to measure or control your system pressures?

• If measuring only, you will need a P-Series pressure transducer. If your medium is a corrosive gas or liquid, we recommend our PS Series, which includes 316L stainless steel construction.
• If controlling pressure, continue below.

Do you need to control a flowing or dead-ended process?

• If flowing, you will need a PC-Series single-valve pressure controller for flow-through processes. To control pressures at points somewhat distant from the pressure controller, choose the PC3 Series, which includes a remote sense port to monitor pressure at any point upstream or downstream of the controller. (Differential pressure controllers by nature use dual remote sense ports.) If you want to monitor your flow rates while controlling for pressure, choose an MC-Series mass flow controller, which can control absolute pressure up to 160 psi(A). Any of these instruments can be configured for backpressure control or vacuum control.
• If dead-ended, you will need a PCD-Series dual-valve pressure controller for closed volumes. To control pressures in closed volumes somewhat distant from the pressure controller, choose the PCD3 Series, which includes a remote sense port to monitor pressure at any point upstream or downstream of the controller. (Differential pressure controllers by nature use dual remote sense ports.) If you want to monitor your flow rates while controlling for pressure, choose an MCD-Series bidirectional mass flow controller, which can control your closed volume’s absolute pressure up to 160 psi(A). Any of these instruments can be configured for vacuum control.