
Manual CWD 2005
Software
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Manual CWD2005.doc
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Day is a list field (Sun, Mon, Tue, etc.). Time and Cycle are value fields.
Program 1: Calibration Monday at 15.00 hours.
Program 2: Calibration every second workday at 12.00 hours.
Program 3: Calibration every day at 23.00 hours.
The calibration gas purge time duration is adaptive and automatically selected by the
software. The instrument looks for end-point stability and this is normally achieved in
6 to 10 minutes, depending on the gas type. After a short period of operation (about 5
minutes) at a value below the programmed stability number, the instrument then
calibrates and automatically switches back to the process gas. If the required stability
is not achieved, the calibration cycle will be aborted after a selected period (usually
10 minutes). A failed calibration will be recorded in the event list and may indicate a
maintenance condition has occurred.
Warning
:
Air can become trapped in the gas supply tubing during installation.
Purge the lines before first calibration or after changing the calibration gas cylinder.
The “Start calibration” command may need to be executed several times.
6.2.1.2.3.
Calibrate
This menu starts the manual calibration cycle and will override any programmed auto
calibration for this one time only. The next auto calibration cycle will then start
normally as programmed by the user.
Manual calibration uses the same routine to verify readings as auto calibration but
automatically adds a memory hold function that allows manual calibration to be
performed by the user at any time, without a spike in the output signal. If an output
signal hold is required during auto calibration, the user can select the hold function
with the keypad from the main menu, a “hold signal on” message will then appear in
the information field to alert the user that this feature is now active.