Teledyne 4020 - Hydrocarbon analyzer User Manual
Page 74
Operation Model
4020
Teledyne
Analytical
Instruments
58
setting is 4 and that should suffice for most applications.
In some applications where speeding the response time
with some trade off in noise is of value, decrease the
value for the digital filter. In applications where the
signal is noisy, increase the value. Decreasing the digital
filter index will result in a slower response time.
4.6.15 Fuel Display
This screen displays the fuel type this instrument is set up for:
40%H2/60%N2, or 100% H2, or 100%N2. It is an information only
screen and has no bearing on the analyzer performance.
4.6.16 Valve Selections
This 4020 analyzer has the option of 3 input streams. The rear panel
of the analyzer has 3 gas inputs labeled: “SAMPLE", "SPAN" and
"ZERO".
The particular gas stream sent to the analyzer can be determined in
one of three ways:
1. Valve selection disabled. This option has the “SAMPLE”
valve always open, typically to deliver sample gas to the
analyzer.
2. User Select . The user can select which port opens to the
analyzer.
3. By Function: In this option, a specific gas port opens to the
analyzer depending on the current mode of the analyzer. For
instance, when performing a zero calibration, the “ZERO”
port would be open while “SAMPLE” and “SPAN” ports
would be closed.
To enable/disable or select a specific valve selection mode:
<▲▼>
From the MAIN MENU, scroll to the VALVE
SELECTIONS function using the UP/DOWN keys.
Press
screen.