Example Gpt Calculation - Teledyne 200E Instruction Manual

Model 200E Instruction Manual

8.2.3. Example GPT Calculation

Following is an example calculation that can be used to determine whether an existing GPT
calibrator will meet the required conditions for a specific calibration. For this example, it is
assumed that only the volume of the reaction cell, V
standard, [NO] , are known. All flow settings (F
STD
many uses, these flow settings are known and need only to be substituted in Equations 8-5
and 8-6 to verify the required conditions. Before doing any calculations, the URL and flow
demand of the analyzer being calibrated must be known. Operating parameters are
determined from the operations manual:
• Upper range limit = 0.5 ppm, and
• Flow demand = 500 cm
• Volume of calibrator reaction cell is determined by physical measurement: V
3
cm
• The concentration of the NO standard gas to be used is determined by reference
against an NIST-SRM (Section 2.0.7, Q.A. Handbook): [NO]
Determine the minimum total flow (F
Because low flows are difficult to control and measure, it is often advantageous to set a
higher total flow than needed. In this example, we will set F
Determine the highest NO concentration, [NO]
Equation 8-2:
Calculate the NO flow (F
Equation 8-3:
Calculate the required flow rate through ozone generator (F
F
Verify that the residence time (t
044100102 Rev A
3
/min.
) required at the output manifold using Equation 8-1:
T
3
F = 500 cm /min (110/100) = 550 cm
T
[NO] = 0.5 ppm (90/100) = 0.45 ppm
OUT
) required to generate the NO concentration [NO]
NO
×
. 0 45 ppm 2750
=
F
NO
50 5 .
50.5 ppm x 24.5
=
O
2.75 ppm
6 2
= 80984 /
cm min
) in the reaction cell is <2 min using Equation 8-5:
R
180
t =
R
3
260 / min
cm
, and the concentration of the NO
RC
, F , F , and F
NO O T
T
, required at the output manifold, using
OUT
3
/ min
cm
=
24.5
cm
ppm
) using Equation 8-4:
O
3 3
/min x 180
cm cm
- 24.5
- min
3
- 24.5 /min = 260
cm
3
cm
=
. 0 63
+
3
24 5 . / min
cm
EPA Protocol Calibration
) will be calculated. In
D
= 50.5 ppm
STD
3
/min
3
to 2750 cm /min.
, using
OUT
3
/ min
3
/ min
cm
3
/min
cm
min
= 180
RC
131