ATI
Model F12/D Gas Transmitter
Part 4
– Operation
34
O&M Manual (Rev-H)
4.3 Main Display
The Main Display Page shows the name and concentration of the target gas, and units of measurement
(PPM, PPB, %, etc). Indicators on the left and below show alarm and operating status.
Figure 35. Main Display
Main Reading
The main reading represents the gas concentration value and appears on the Main Display, along with
the gas name and units of concentration, and is reported on the 4-20mA output
1,2
. By default, it is
blanked to suppress the display of negative values. That is, the reading is reported as zero if the
concentration drifts below zero, which can occur over time as a result of sensor aging. If the
concentration falls to
–20% of the full-scale range, a trouble alarm is generated. Blanking is typically
extended slightly above zero, as a means of stabilizing the reading in the presence of excessive external
noise, or other environmental factors (see Sensor Settings Menu on pg 38). During zero and span
calibration, the “un-blanked” gas concentration value is displayed, primarily to assess the amount of
positive or negative drift.
1
The 4-20mA may not match the reading when the status indicator is visible on the Main Display, or when the output
is in a physical limit.
2
Throughout this manual, “ghosted” status icons are used to indicate status that may be present or not present.
Over-range/Under-range
Gas concentration at or
above 100% range
Gas concentration at or
below -20% range
Alarm Indicators
Main Display
PPM
H2S
A
MENU
W
C
!
0.0
Menu Icon
Selects the main menu.
Gas Name
Identifies target gas.
Units of Measurement
PPM, PPB, %, %LEL
Main Reading
Trouble (!)
Select to view problem(s).
Alarm (A)
Select to view date and time
of alarm and manually reset.
Caution (C)
Select to view date and time
of alarm and manually reset.
Warning (W)
Select to view date and time
of alarm and manually reset.
Status Indicators
Sensor warm-up, alarms inhibited (animated hourglass)
Alarms inhibited (blinking bell with slash)
4-20mA output fixed (animated down arrow)
Auto-test ready (steady) or active (blinking)
Data logger active
Security on (password required to modify settings)
(blinking) Security off, but auto-relock timer is running
The presence of an icon indicates the associated status is active.
Select the group to view a brief description on the display.
Note: “ghosted” icons
appearing throughout
this manual represent
status that may, or may
not, be present.
