Manual

4 Operation Model 1220
4-8
Teledyne Analytical Instruments
a. Press the up or down arrow key until the display reads “0”.
b. Press ENTER.
4. (B) Disconnect the zero gas from the sensor.
5. (A) If necessary, proceed to the previous or next procedure. Other-
wise, press RUN to place the instrument in the analysis mode.
4.4.2 Span Calibrating a Single Sensor Channel Module
NOTE: To accomplish the following task, two operators are needed.
Operator one at the Control Unit and operator two at the
probe. Both operators are involved in the calibration process.
They must be in constant communication, by phone or other
means.
(A) = Operator One at the Control Unit
(B) = Operator Two at the probe
1. (A) At the Front Panel of the Channel Module to be calibrated:
a. Press SELECT.
b. Use the right or left arrow key to highlight the SPAN option.
c. Press ENTER.
Result: Alarms are deactivated and the SPAN display
option flashes.
2. (B) Introduce span gas into sensor.
3. (A) After the reading stabilizes:
a. Press the up or down arrow key until the display reads the value
that corresponds to the LEL of the certified span gas used.
NOTE: Information about calibration valves for various com-
bustible gases appears in Table 1 on page 2-5 and in Section
4.11 on page 4-14
NOTE: If you need to adjust the Sensitivity Gauge, see Paragraph 4.8
for recommendations.
b. Press ENTER.
4. (B) Disconnect the span gas from the sensor.
5. (A) If necessary, proceed to the previous or next procedure. Other-
wise, press RUN to place the instrument in the analyze mode.