Thermo Scientific TVA2020, Instruction Manual

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Optional Accessories
Enhanced Probe Option
Thermo Fisher Scientific TVA2020 Instruction Manual 8-7
6. Once you have saved a reading, you may enter another tag and begin
logging again or exit from the RUN mode.
In FE logging, you follow a preconfigured route list consisting of
component records for equipment to be monitored. You should first
download a route to the TVA2020’s memory before entering the RUN
mode. For more information on downloading routes, see the “
Memory ”
section in Chapter 3.
In the RUN mode, from the Opening menu, press the select key to “Enter
logging mode.”
PID
0.66
ppm
Tag:0033
Eqp:CMP Size: 0.00
Leak: 600 RF:0.80
0.66ppm LastLog
[Start log sampling]
-Nx -Pr -List -Exit
In addition to the concentration display at the top, the FE mode shows
several fields which have been filled in by the downloaded route. The
TVA2020 starts at the first record in the route and displays the component
tag number (Tag), equipment type (Eqp), equipment size (Size), and leak
definition (Leak). If a reading has already been logged into memory for this
record, it will also be displayed followed by the words “LastLog.”
A secondary response factor correction is based on the response factor
associated with the current route entry. This secondary correction adjusts
the concentration reading for different component measurements in the
same route.
For example, let a route contain two entries, one for propane and one for
methane. Assume that propane has only half the detector response of
methane. If each route location has a leak of 100 ppm, a single response
factor based on methane would produce a concentration reading of 100
ppm for methane, but only 50 ppm for propane. The addition of a
secondary response factor allows each entry to be corrected for detector
sensitivity. Thus, if the secondary response factor is 1.0 for methane and
2.0 for propane, both route samples will read correctly as 100 ppm.
FE Logging with the
Enhanced Probe
Route Entry Response
Factor