ATI
Model F12/D Gas Transmitter
Part 4
– Operation
41
O&M Manual (Rev-H)
Sensor Calibration Menu
Figure 47. Sensor Calibration Menu
Sensor Zero Calibration
Performing a zero calibration requires a bottled “Zero-gas” with a 500 cc/min regulator, calibration adapter,
and a convenient length of ¼” tubing. The gas used depends on the type of sensor installed. For example,
an H
2
S sensor may be zeroed with Zero-air, however, Oxygen sensors must be zeroed with Nitrogen. In
some cases, a sensor may be zeroed directly to the atmosphere, but only when it is known to be free of
reactive gasses. Check with the factory if you are uncertain about which gas to use.
Referring to Figure 48, push the
calibration adapter onto the exposed
end of the sensor and connect one
end of the tubing (1), connect the
other end of tubing to the cylinder’s
regulator (2). Do not open the gas
valve until instructed below.
Select the Zero method from the
Sensor Calibration menu, as shown
in Figure 49
. This will clear and
inhibit alarms at the transmitter, and
hold the current loop output at 4mA
(17.4mA for Oxygen sensors) for up
to 30 minutes of no key activity.
Figure 48. Sensor Zero Cal. Setup
Figure 49. Sensor Zero Cal.Menus
Open the regulator to flow gas to the sensor. After approximately four minutes, select Zero. “Cal” will
appear briefly at the bottom of the page and the reading will be forced to 0, 0.0, or 0.00. Since the
reading is not blanked, it may show a negative
sign, like “-0.0”, which is normal. Press the
Esc
key twice
to return to the Main page. Alarms will remain inhibited, and the current loop will be fixed for 30 minutes
after calibration.
6
The zero method is also directly accessible from the main menu.
Item
Select to …
Zero
Calibrate the gas sensor zero reading (below). Note
– this item
also appears in the Main Menu (see Figure 39. Main Menu)
Span
Calibrate the gas sensor sensitivity (below). Note
– this item also
appears in the Main Menu (see Figure 39. Main Menu).
Temp
Adjust the gas sensor’s temperature reading offset. Note: this
reading may be slightly higher than ambient temperature due to
self-heating. Contact the factory before adjusting.
History
View the transmitter calibration records.
Calibration
►Zero History
Span
Temp= 21.1°C
…Sensor>Calibration
1
2
PPM
H2S
►Zero
Cal
…Calibration>Zero
0.0
Calibration
►Zero History
Span
Temp= 21.1°C
…Sensor>Calibration
