You searched for a McMillan product! See what Sierra has to offer for your Mass Flow Meter or Mass Flow Controller needs.

You may have used one of the following spellings Mcmillan mcm mcmflow mcmilan mcmilin mcmflow meater meater flo controler controlers controller 

Allow me to explain why Sierra Instruments Mass Flow Meters and Controllers will provide superior performance compared to the Mcmillan pressure pased Mass Flow Meters and Controllers. We will answer the question by posing the question you may have about the difference between Thermal Mass Flow Meters and Controllers and Pressure difference based flow measuring instruments. You will ALSO find it educational to know that Sierra is the ONLY company that calibrates EVERY Mass Flow Meter and Mass Flow Controller using a primary standard. See the descriptions below!

Why is a Thermal Mass Flow meter better than a Pressure Based Flow Transducer?
Great question! We hear this all the time and it is why the Sierra meter is such a popular a choice by scientists and technicians “in the know”. Sometimes the pressure based flow transducers are called Volumetric or Mass Flow Meters. A pressure based meter is essentially a "Volumetric" device with the addition of the corrections required to compensate for the flowing gas, pressure, temperature and other second and third order effects. Once the temperature, pressure, and other gas properties are known an on-board computer can manipulate the variables to indicate any of the desired parameters. One of the leading problems is these meters are difficult to properly "correlate" because the mechanical construction of the orifice, or pressure creating means, requires VERY CRITICAL dimensions and fabrication techniques in order to properly follow the theory that dictates their operation. As such some companies invoke "K-Factors" that attempt to overcome these difficult and costly manufacturing procedural shortcomings. Once one invokes a "K factor" to correct the basic operation of a meter we expose the difficulties in matching Primary Flow calibration checks. The Sierra Thermal Mass Flowmeter line has illustrated an extraordinary ability to follow the theory dictating it's principle of operation. It is also EXTREMELY important to note that no other company, on the planet, calibrates EVERY SINGLE flow meter with Primary Standards. This is because Sierra invented the first Automated Primary Standard Calibration system that was sold for more than 15 years and is installed in nearly every standards lab as well as the standard at the Swiss Metrology Laboratory in Switzerland .Mcmillan mcm mcmflow mcmilan mcmilin mcmflow meater meater flo controler controlers controller 

How does Sierra calibrate mass flow meters?
Every single 800 Series Sierra Flow meter is calibrated on a Primary Standard. Sierra does NOT use transfer standards. We can not stress how beneficial this is to YOU as the end user! The reason nobody else calibrates EVERY meter on a Primary Standards because the cost to calibrate Flow Meters with Primary Standards is IMMENSE however it is TRULY the ONLY way any company manufacturing Mass Flow Meters with accuracies of 1% or better could justifiably make such claims of accuracy. Sierra has been around for more than 30 years and has made substantial investments in the calibration facility that makes your flow meters. Sierra strictly maintains the classic four-to-one ratio of propagated transducer uncertainties at every calibration step. That is, in a calibration uncertainty propagation chain, the subject mass flow transducer (unit under test) can only be calibrated by a "standard transducer" that itself has an uncertainty approaching one-fourth that of the unit-under-test. This level of commitment to flow measurement accuracy requires that Sierra base their laboratory Flow measurement standards upon Primary Piston Provers that have been calibrated using NIST traceable measurements of EVERY parameter involved. Sierra does this in order to drive the initial uncertainties to the minimum possible level. The ONLY way to do this, it turns out, for measuring gas flow in the ranges you are looking at, is to utilize a Primary Standard Piston prover. NIST refers to these systems as a PVTt system, meaning Pressure, Volume Temperature and time. As such the Sierra "standard transducer" happens to be a Primary Piston Prover. Sierra does NOT use nozzles, laminar flow elements or "secondary standards" as the justification of the uncertainty would not support the claim of anything better than 1% uncertainty or "accuracy" as we so incorrectly refer to it. What YOU get is a flow meter calibrated using the best calibration system in the world. The reference to the classic four-to-one can be found many places in the NIST website at:NIST Home Page Please forgive our industries incorrect use of the term "accuracy" (as well as using units such as SCCM for mass instead of g/m). We all really know the term is an abstract one and should be replaced with the term "uncertainty". Indeed, it makes more sense to describe the uncertainty of an instrument rather than the accuracy. I recall lessons given to me by Dr. George Mattingly, Deputy Division Chief of the Process Measurements Division of NIST, goes something like this: So you have an instrument that carries an accuracy of 1%? So, does that means it is 99% inaccurate? I am guessing it will take another 40 years for this industry to "abandon" the incorrect use of the term accuracy, till then we have what we have, right along with SCCM. Please take advantage of our calibration and maintenance packages that give you from 1 to 3 future calibrations at very reasonable prices. Click on the “About Us & Terms” button at the left. Mcmillan mcm mcmflow mcmilan mcmilin mcmflow meater meater flo controler controlers controller 

Click on one of the six variations below to order now

Select one of the three variations of Sierra Mass Flow Meters or Mass Flow Controllers with digital displays from the graphics and flow range selections below.
Mass Flow Meter with Display	Mass Flow Meter with Display	Mass Flow Controller with Display
Flow ranges 10 sccm to 50 slpm	Flow ranges 1 slpm to 175 slpm	Flow ranges 10 sccm to 50 slpm
Sierra 822 Series Click to Order	Sierra 826 Series Click to Order	Sierra 810C-DR Series Click to Order
Priced From $540	Priced From $840	Priced From $945
Select one of the three variations of Sierra Mass Flow Meters or Mass Flow Controllers from the graphics and flow range selections below.
Mass Flow Meter	Mass Flow Meter	Mass Flow Controller
Flow ranges 10 sccm to 50 slpm	Flow ranges 1 slpm to 175 slpm	Flow ranges 10 sccm to 50 slpm
Sierra 824 Series Click to Order	Sierra 827 Series Click to Order	Sierra 810C-NR Series Click to Order
Priced From $490	Priced From $790	Priced From $895