Teledyne 4020 - Hydrocarbon analyzer - Manual (Page 56)

Operation Model 4020
Teledyne Analytical Instruments 40
4.6.6 Setting up an AUTO-CAL
If the analyzer is equipped with the optional auto-calibration feature
(see Chapter 3, Installation), the analyzer can cycle itself through a
sequence of steps that automatically zero and span the instrument (auto
calibration or autocal).
Note: Before setting up an AUTOCAL, be sure you understand
the Zero and Span functions as described in Section
4.6.14, and follow the precautions given there.
Note: If you require highly accurate AUTOCAL timing, use
external AUTOCAL control where possible. The internal
clock in the Model 4020 is accurate to 2-3 %. Accordingly,
internally scheduled calibrations can vary 2-3 % per day.
Note: By default, AUTOCAL is off.
To setup an AUTOCAL cycle for a zero or span event to occur in a
certain number of days:
Press any key to enter the Setup Mode. The VFD will
display the first 2 lines of functions available.
<▲▼> If the arrow is not adjacent to the AUTOCAL menu item,
use the ▲▼ keys to move the arrow to the proper
position.
<Enter> Press to activate the function and move you to
the next screen.
This screen allows you to either enable or disable the AUTOZERO
or AUTOSPAN functions independently. To set up an autocal event,
the appropriate AUTOCAL function (AUTOZERO and/or AUTOSPAN
must be enabled.
<▲▼> If the screen indicates the specific AUTOCAL function is
disabled, press , then use the <▲▼> keys to
toggle the enable/disable feature.