Use Of Zero/Span Valve With Remote Contact Closure; Automatic Zero/Span Cal/Check (Auto Cal) - Teledyne T400 User Manual

4.2.2.1 USE OF ZERO/SPAN VALVE WITH REMOTE CONTACT CLOSURE

Contact closures for controlling calibration and calibration checks are located on the rear
panel CONTROL IN connector. Instructions for setup and use of these contacts are in
Section 2.3.1.5.
When the contacts are closed for at least 5 seconds, the instrument switches into zero,
low span or high span mode and the internal zero/span valves will be automatically
switched to the appropriate configuration.
The remote calibration contact closures may be activated in any order.
•
• It is recommended that contact closures remain closed for at least 10 minutes to establish a
reliable reading.
• The instrument will stay in the selected mode for as long as the contacts remain closed.
If contact closures are being used in conjunction with the analyzer's AutoCal (see
Section 4.3) feature and the AutoCal attribute "Calibrate" is enabled (selection box is
checked), the analyzer will not recalibrate the analyzer UNTIL the contact is opened. At
this point, the new calibration values will be recorded before the instrument returns to
SAMPLE mode.
If the AutoCal attribute "Calibrate" is disabled (selection box is unchecked), the
instrument will return to SAMPLE mode, leaving the instrument's internal calibration
variables unchanged.
4.3

AUTOMATIC ZERO/SPAN CAL/CHECK (AUTO CAL)

The Auto Cal feature allows unattended periodic operation of the ZERO/SPAN valve
options by using the instrument's internal time of day clock. Auto Cal operates by
executing preprogrammed calibrations or calibration checks set up by the user to initiate
the various calibration states of the analyzer and to open and close valves appropriately.
It is possible to set up and run up to three separate preprogrammed calibrations or
calibration checks (labeled # 1, 2 and 3). Each calibration or check can operate in one of
three modes (Zero, Low or High), or be disabled.
Table 4-1 and Table 4-2 show how to set up the operating states of each calibration or
check, and Table 4-3 shows how to program the execution of each.
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Teledyne API – Model T400 O Analyzer 083730400A DCN8130
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