Teledyne 200A, Instruction Manual, Page: 106 / 220

Teledyne API Model 200A NO
X
Analyzer Instruction Manual, 02246, Rev. F1
NOTE
If t
r
is >2 minutes or if P
R
is <2.75 ppm-min, changes in flow conditions
(F
T
, F
O
, F
NO
) or in the reaction chamber volume (V
RC
), or both will
have to be made, and t
r
and P
R
will have to be re-calculated.
9.
After equations 7-5 and 7-6 are satisfied, calculate the diluent air flow (F
D
) using
Equation
7-7:
N O T D
F F F
− − =
O
F Equation 7-7
7.8.4.3 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 chamber, V
RC
, and the concentration of the NO
standard, [NO]
STD
, are known. All flow settings (F
NO
, F
O
, F
T
, and F
D
) will be calculated. In many
uses, these flow settings are known and need only to be substituted in Equations 7-5 and 7-6 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
3
/min.
Volume of calibrator reaction chamber is determined by physical measurement:
V
RC
= 180 cm
3
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]
STD
= 50.5 ppm
1. Determine the minimum total flow (F
T
) required at the output manifold using Equation 7-
1:
F
T
= 500 cm
3
/min (110/100) = 550 cm
3
/min
7-18