So little system impact it can run on just a whisperLow pressure drop minimizes system impact, enabling flow measurement and control at near-atmospheric pressures, perfect for aerospace and environmental gas analysis applications. Reduced pressure drop also means more process fluids go into your process and not into your measurement devices.
Brochure Specs Manual
Making You Faster
- Low pressure drop enables faster stabilization for leak testing applications.
- All flow data visible on one screen (mass flow, volumetric flow, absolute pressure, temperature).
- No warm-up required: ready to operate in one second.
- 5-ms speed of response for meters, 50-100 ms for controllers.
- Accessible PID control valve tuning for best speed and stability.
- Control mass flow, volumetric flow or absolute pressure with one device.
- Numerous user-selectable engineering units.
- Includes COMPOSER™ gas composition firmware.
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MW Low Pressure Drop Flow Meters
- Alicat MW-Series Part NumbersMW-0.5SCCM-D
MW Specs Go to Meter page.
MCW/MCRW Low Pressure Drop Flow Controllers
- Alicat MCW-Series Part NumbersMCW-0.5SCCM-D
MCW Specs Go to Controller page.
MCDW/MCRDW Low Pressure Drop Bidirectional Flow Controllers
- Alicat MCDW-Series Part NumbersMCDW-0.5SCCM-D
MCD standard Specs Go to MCD page.
MWB Low Pressure Drop Portable Flow Calibrators
- Alicat MWB-Series Part NumbersMWB-0.5SCCM-D
MWB Specs Go to Portables page.
Common Instrument Options
- High-accuracy calibration, permits use of the meter as a secondary transfer standard.
- Bidirectional flow calibration, enables full-scale readings in both flow directions.
- Downstream valve, optimizes control in vacuum conditions or backpressure applications.
- Integrated flow totalizer, provides cumulative readings of total quantity flowed over time.
- CSA Class 1 Division 2 (ATEX Zone 2) Area Classification, permits operation in hazardous environments.
- 9-pin or 15-pin D-sub connectors, configured to match any existing pinout.
- Modbus-RTU, available over RS-232 or RS-485. PROFIBUS also available.
- Backlit color display, shines in low lighting environments.
View other available instrument options here.
- Standard accuracy (NIST-traceable): +/- (0.8% of the reading + 0.2% of the full-scale range)
- Optional high-accuracy calibration: +/- (0.4% of the reading + 0.2% of the full-scale range)
- Accuracy specs apply to preloaded and COMPOSER™ gas calibrations.
- Typical flow reading response time constant: 5 ms (may be up to 10 ms under very low flow conditions)
- Standard control response time constant: 50 ms (MCW/MCDW series)
- High-flow control response time constant: 100 ms (MCRW/MCRDW series)
- Whisper meter and controller ranges: any full-scale range from 0-0.5 sccm to 0-500 slpm
- Standard linear range: 0.5-100% of full scale, 200:1 turndown
- Maximum line pressure: 50 psig
- Pressure drop: 0.06-0.69 psi at full scale, depending upon flow range
- Standard communications: RS-232 digital and 0-5 volt analog
- Optional analog communications: 1-5v, 0-10v, 4-20 mA; secondary outputs also available
- Optional communications protocols: RS-485, Modbus RTU (over RS-232 or RS-485), PROFIBUS
- Standard connector: 8-pin mini-DIN
- Optional connector: 9-pin or 15-pin D-sub connectors, configured to match any existing pinout
- Simultaneous real-time readings of setpoint, mass flow, volumetric flow, absolute pressure and temperature
- Standard display: 2.1″ monochrome LCD digital display with touch pad interface
- Optional 2.1″ backlit color TFT digital display with touch pad interface
- Limited lifetime warranty
- Controller unaffected by bumps, humidity or changes in orientation
Gas Select™ 5.0 Gas List for Alicat Mass Flow Meters and ControllersAll 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.)
|Pure Gases||Bioreactor Gas Mixes||Pure Corrosives|
|• Acetylene (C2H2)|
• Argon (Ar)
• i-Butane (i-C4H10)
• n-Butane (n-C4H10)
• Carbon dioxide (CO2)
• Carbon monoxide (CO)
• Deuterium (D2)
• Ethane (C2H6)
• Ethylene/Ethene (C2H4)
• Helium (He)
• Hydrogen (H2)
• Krypton (Kr)
• Methane (CH4)
• Neon (Ne)
• Nitrogen (N2)
• Nitrous Oxide (N2O)
• Oxygen (O2)
• Propane (C3H8)
• Sulfur Hexafluoride (SF6)
• Xenon (Xe)
|• 5% CH4 95% CO2|
• 10% CH4 90% CO2
• 15% CH4 85% CO2
• 20% CH4 80% CO2
• 25% CH4 75% CO2
• 30% CH4 70% CO2
• 35% CH4 65% CO2
• 40% CH4 60% CO2
• 45% CH4 55% CO2
• 50% CH4 50% CO2
• 55% CH4 45% CO2
• 60% CH4 40% CO2
• 65% CH4 35% CO2
• 70% CH4 30% CO2
• 75% CH4 25% CO2
• 80% CH4 20% CO2
• 85% CH4 15% CO2
• 90% CH4 10% CO2
• 95% CH4 5% CO2
|*These gases require MS/MCS-Series instruments.
• Ammonia (NH3)
• Butylene (1-Butene)
• Cis-Butene (cis-2-Butene)
• Carbonyl Sulfide (COS)
• Chlorine (Cl2)
• Dimethylether (CH3OCH3)
• Hydrogen Sulfide (H2S)
• Nitrogen Trifluoride (NF3)
• Nitric Oxide (NO)
• Propylene (C3H6)
• Silane (SiH4)
• Sulfur Dioxide (SO2)
|Breathing Gases||Fuel Gas Mixes||Refrigerants|
|• EAN-32 (32% O2+68% N2)|
• EAN-36 (36% O2+64% N2)
• EAN-40 (40% O2+60% N2)
• EA-40 (40% O2+60% Air)
• EA-60 (60% O2+40% Air)
• EA-80 (80% O2+20% Air)
• Heliox-20 (20% O2+80% He)
• Heliox-21 (21% O2+79% He)
• Heliox-30 (30% O2+70% He)
• Heliox-40 (40% O2+60% He)
• Heliox-50 (50% O2+50% He)
• Heliox-60 (60% O2+40% He)
• Heliox-80 (80% O2+20% He)
• Heliox-99 (99% O2+1% He)
• Metabolic Exhalant (16% O2+78.04% N2+5% CO2+0.96% Ar)
|• Coal Gas 50% H2+35% CH4+10% CO+5% C2H4|
• Endothermic Gas 75% H2+25% N2
• HHO 66.67% H2+33.33% O2
• LPG HD-5 96.1% C3H8+1.5% C2H6+0.4% C3H6+1.9% n-C4H10
• LPG HD-10 85% C3H8+10% C3H6+ 5% n-C4H10
• Nat Gas 93% CH4+3% C2H6+1% C3H8+2% N2+1% CO2
• Nat Gas 95% CH4+3% C2H6+1% N2+ 1% CO2
• Nat Gas 95.2% CH4+2.5% C2H6+0.2% C3H8+0.1% C4H10+1.3% N2+0.7% CO2
• Syn Gas 40% H2+29% CO+20% CO2+11% CH4
• Syn Gas 64% H2+28% CO+1% CO2+7% CH4
• Syn Gas 70% H2+4% CO+25% CO2+1% CH4
• Syn Gas 83% H2+14% CO+3% CH4
|*These gases require MS/MCS-Series instruments.
• R-11 Trichlorofluoromethane (CCl3F)
• R-14 Tetrafluoromethane (CF4)
• R-22 Difluoromonochloromethane (CHClF2)
• R-23 Trifluoromethane (CHF3)
• R-32 Difluoromethane (CH2F2)
• R-115 Chloropentafluoroethane (C2ClF5)
• R-116 Hexafluoroethane (C2F6)
• R-124 Chlorotetrafluoroethane (C2HClF4)
• R-125 Pentafluoroethane (C2HF5)
• R-134A Tetrafluoroethane (CH2FCF3)
• R-142B Chlorodifluoroethane (CH3CClF2)
• R-143A Trifluoroethane (C2H3F3)
• R-152A Difluoroethane (C2H4F2)
• RC-318 Octafluorocyclobutane (C4F8)
• R-404A (44% R-125+4% R-134A+52% R-143A)
• R-407C (22% R-32+25% R-125+52% R-134A)
• R-410A (50% R-32+50% R-125)
• R-507A (50% R-125+50% R-143A)
|Chromatography Gases||Oxygen Concentrator Gas Mixes|
|• P-5 (5% CH4+95% Ar)|
• P-10 (10% CH4+90% Ar)
|• 89% O2+7% N2+4% Ar|
• 93% O2+3% N2+4% Ar
• 95% O2+1% N2+4% Ar
|Welding Gases||Stack/Flue Gas Mixes||Laser Gas Mixes|
|• C-2 (2% CO2+98% Ar)|
• C-8 (8% CO2+92% Ar)
• C-10 (10% CO2+90% Ar)
• C-15 (15% CO2+85% Ar)
• C-20 (20% CO2+80% Ar)
• C-25 (25% CO2+75% Ar)
• C-50 (50% CO2+50% Ar)
• C-75 (75% CO2+25% Ar)
• He-25 (25% He+75% Ar)
• He-50 (50% He+50% Ar)
• He-75 (75% He+25% Ar)
• He-90 (90% He+10% Ar)
• A1025 (90% He+7.5% Ar+2.5% CO2)
• Stargon CS (90% Ar+8% CO2+2% O2)
|• 2.5% O2+10.8% CO2+85.7% N2+1% Ar|
• 2.9% O2+14% CO2+82.1% N2+1% Ar
• 3.7% O2+15% CO2+80.3% N2+1% Ar
• 7% O2+12% CO2+80% N2+1% Ar
• 10% O2+9.5% CO2+79.5% N2+1% Ar
• 13% O2+7% CO2+79% N2+1% Ar
|• 4.5% CO2+13.5% N2+82% He
• 6% CO2+14% N2+80% He
• 7% CO2+14% N2+79% He
• 9% CO2+15% N2+76% He
• 9.4% CO2+19.25% N2+71.35% He
• 9% Ne+91% He
Ask Alicat: What Is Pressure Drop?
Pressure drop is the amount of line pressure that is permanently lost as gas passes through an instrument in a gas line. Alicat Scientific demonstrates the importance of pressure drop for gas flow processes and shows how you can greatly reduce pressure drop by using its Whisper Series of mass flow instruments.
Ask Alicat: How fast is an Alicat mass flow controller?
Flow stability and accuracy depend on fast control response, and Alicat is the fastest. This video demonstrates 0 to 100% setpoint changes with settling times of less than 30 ms and control T/C of only 7.4 ms.
Ask Alicat: What is the fastest way to validate flow rates?
Alicat Scientific’s rechargeable mass flow meters deliver laboratory-class accuracy in a handheld instrument that lasts 18 hours on a single charge.
The Fastest Flow Controller Company in the World
How can Alicat claim to be the fastest flow controller company in the world? This video introduces you to some of the many ways that Alicat mass flow and pressure instruments can make you more efficient, saving you time and money.
Ask Alicat: How tough is an Alicat flow meter? (Drop Test)
We drop an Alicat portable mass flow meter onto unforgiving concrete from increasing heights to test the toughness of this product. After each drop, we compare its measurement to the pre-test baseline.
Alicat Turndown Ratio for Mass Flow
Alicat demonstrates an incredible 5000:1 turndown ratio, commanding a 5 slpm (5000 sccm) mass flow controller to control down to 1 sccm!
Ask Alicat: How do you control flow in TWO directions?
Alicat Scientific introduces the world’s first bidirectional flow and pressure controller: the dual-valve MCD. Control mass flow, volumetric flow and pressure in both directions with stand-alone control and 30 on-board gas calibrations over a 200:1 turndown range. Or control pressure or flow into a closed process, and vent the volume with no need for additional bleed valves or continuous outgassing. The MCD is the single most versatile flow controller in the world.
In the Box
- Mass flow meter or controller (power supply sold separately, except for calibrators)
- NIST-traceable calibration certificate
- Alicat meter or controlleroperating manual
Calibration of an Air Sampling Canister
Rapidly calibrate across multiple ranges and gases without carrying a computer. NIST-traceable high-accuracy calibration makes your portable a transfer standard. “Whisper” low pressure drop enables non-intrusive volumetric flow calibration.
See the full app note here.
Even Faster Leak Testing
For leak checking smaller test volumes, such as valves or sensors, a single MCW “Whisper” mass flow controller that is set to control for pressure will maintain a constant pressure at the device under test while providing accurate mass and volumetric flow readings in real time. Configured this way, the Whisper serves the functions of both a pressure controller and a mass flow meter in one device.
See the full app note here.