Total Hydrocarbon (THC) is a measurement of the hydrocarbon content (aggregated, not specific to an individual HC compound) concentration in a measured sample.
A Flame Ionization Detector (FID) analyzer tests for the presence and concentration of select compounds in a gaseous test sample by ionizing the compound of interest with a controlled combustion reaction.
The 400A Flame Ionization Detector (FID) THC analyzer tests for the presence and concentration of HC compounds in a continuous gaseous sample by combining the sample with a fuel gas stream, ionizing the present hydrocarbons through combustion, and then measuring proportional charge produced by the presence of the ionized hydrocarbons in the sample.
(Video Link – short operational overview video)
(Video Link – in-depth overview video)
Overview of the 400A (PDF) <<(Not the same as the above PDF?)
Need drawings? <<(See Drawings tab?)
Need assistance? <<(See Problem/Solution tab?)
First, there was the Beckman 400. This unit dates back to the 1970’s; it sported a heavy duty metal case, an analog meter, a bull’s eye flame status indicator, and the necessary electronics.
Second, came the Beckman 400A with new electronics, a better preamplifier board, and a notched case (the fuel solenoid is exposed and hangs out the back). It was quickly renamed Rosemount 400A as this was during the transition of when Emerson/Rosemount acquired Beckman Industrial.
The Third revision is our favorite, the Rosemount 400A (square case; no notch). This has the standard Main Electronics Board (one of two possible versions), the better Preamplifier Board (only one tried and true version that we know of), the better case heater assembly (a fan, heater, and dedicated proportional controller circuit board, and one of three versions of the Flame Safety Board.
The last version, the fourth and present version, sports miniaturization of the Main Electronics Board, 4-20 mADC daughter board, and case heater controller board. Everything is driven by a 24 vDC off-the-shelf DIN mounted power supply. The result was the Rosemount 400A . . . We know, it’s confusing. That’s why we call it the “Rosemount 400A-circa 2009 analyzer.” Here’s the link to that specific page.
What’s next? How about the Rosemount 400R? It’s the 400A but enhanced and built by RIGAS, but sold through the vast Rosemount sales channels. You’ll have to ask your local Rosemount Sales Rep to ping on his upper management in order to make the 400R something to purchase. You’ll like it – it will have the same great little burner, same Brooks regulators, same Siemens-Moore Products backpressure regulator, similar pneumatics, and the same Rosemount Preamplifier Board. But beyond that, RIGAS is going to fully digitize the Main Electronics Board so that it can read out in percent of scale (as it presently does) or part per million (ppm) of any hydrocarbon molecule that you can think of. It will also have diagnostics to give the user some insight as to what’s occurring within the analyzer (temperatures mainly but pressures and key voltages too).
Click here for a PDF overview of the 400/400A.
The RIGAS 400A Calculator
The 400A Calculator is an interactive MS Excel spreadsheet for use in determining optimal operational parameters, settings, and expected readings, given user-entered details of the use application. The 400A Calculator spreadsheet is available for download below; please view the tutorial video for instructions on using the spreadsheet.
Download the 400A calculator here (Zip Archive)
Video Tutorial – PH