User's Manual

M400E Calibration Procedures M400E Ozone Analyzer Operator’s Manual
9.3.2.3. 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 found in Section 3.3.4.
Whe
n 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 9.4) feature and the
AutoCal attribute “
CALIBRATE” is enabled, the M400E will not re-calibrate the analyzer UNTIL when 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, the instrument will return to SAMPLE mode, leaving the
instrument’s internal calibration variables unchanged.
9.4. AUTOMATIC ZERO/SPAN CAL/CHECK (AUTOCAL)
The AutoCal system allows unattended periodic operation of the ZERO/SPAN valve options by using the
M400E’s internal time of day clock. AutoCal operates by executing
SEQUENCES programmed by the user to
initiate the various calibration modes of the analyzer and open and close valves appropriately. It is possible to
program and run up to three separate sequences (
SEQ1, SEQ2 and SEQ3). Each sequence can operate in one
of three modes, or be disabled.
Table 9-1: AUTOCAL Modes
MODE NAME ACTION
DISABLED
Disables the Sequence.
ZERO
Causes the Sequence to perform a Zero calibration/check.
ZERO-LO
Causes the Sequence to perform a Zero and Low (Midpoint) Span concentration
calibration/check.
ZERO-HI
Causes the Sequence to perform a Zero and High Span concentration
calibration/check.
ZERO-LO-HI
Causes the Sequence to perform a Zero, Low (Midpoint) Span and High Span
concentration calibration/check.
LO
Causes the Sequence to perform a Low Span concentration calibration/check only.
HI
Causes the Sequence to perform a High Span concentration calibration/check only.
LO-HI
Causes the Sequence to perform a Low (Midpoint) Span and High Span
concentration calibration/check but no Zero Point calibration/check.
162 04315 Rev. C1