This dilution system main purpose lies in the mixing of a span gas ranging from low to high ppm purity with a zero background gas in order to decrease the concentration of the span by producing a blended output. This dilution result is then used in the calibration of your equipment.
To mix the gases together, the span gas flow is added to the main path in which flows the zero background gas. The software uses the following formula to calculate and display in real time the concentration of the blended output:
[Blend] = [Zero] x Fz + [Span] x Fs
Fb
| Where |
- Fz = zero gas flow
- Fs = span gas flow
- Fb = blended gas flow (Fb = Fz + Fs)
- [Zero] = zero background gas concentration (can contain any impurity)
- [Span] = span gas concentration (can contain any impurity)
- [Blend] = blended gas concentration
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| Example |
- Take a span gas of 2ppm of H2 and 5 ppm of O2 in a balance of Ar (999993 ppm);
- Let it flow in the DCS-100 at 1 cc/min;
- Take a zero background gas of pure Ar;
- Let it flow in at 499 cc/min;
- You will obtain a blended gas of 4.0 ppb of H2, 10.0 ppb of O2 and 999999.99 ppm of Ar.
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