Operation
Digital Display Codes (
continued
)
AC
These codes appear on the display
CP
during the calibration process. For
CC
more information about these codes,
refer to Section 4.1 Calibration.
F1,F2,F3,
These codes will appear on the
F4,F5,F6,
display if a Fault condition occurs.
F7,F8,F9
For more information about these
codes, refer to Section 4.3 Fault
Codes & Their Remedies.
4.3
Fault Codes & Their Remedies
The Model S104 has self-diagnostics incorpo-
rated into the microprocessor’s program. If a
Fault is detected, the output signal will drop to
0mA and a Fault code will be displayed. The
output signal will inform a remote display
module that the Model S104 is in the Fault
Mode. The display will indicate a Fault code
that can be viewed at the sensor site. There
are nine Fault conditions that are monitored by
the microprocessor.
When a Calibration Fault (F1, F2, F3) has oc-
curred and has been corrected, the unit will
automatically revert to the calibration process
and the unit must be re-calibrated.
If a Fault
other than a Calibration Fault occurs, after it is
corrected, the unit will return to the Start-Up
Mode (SU).
F1 = Failed to Zero during Calibration
Faulty Sensor - If both Catalytic Beads are
not closely matched. This may happen as a
sensor approaches the end of its useful life or
if the Beads have become corroded.
AC-
TION - Replace the sensor.
Gas Present - If the magnet was applied with
a high level of gas present, the Model S104
will not be able to obtain a valid ZERO. AC-
TION - Ensure the sensor is in clean air.
F2 = Failed to complete the Calibration
This Fault will occur if the unit is placed in the
calibration mode and no gas has been applied
within six minutes.
F3 = Failed to Span during Calibration
Low Gas - If the gas concentration applied to
the unit does not give sufficient response for a
valid SPAN parameter. ACTION - Use the
correct gas concentration, i.e. 50% LEL.
Bad Sensor - If the sensor response has gone
below an acceptable level. ACTION - Re-
place the sensor.
NOTE: If the unit fails to calibrate and an F1
or an F3 code is displayed, the calibr ation
gas must be r emoved fr om the sensor and
the sensor must see clean air for at least five
minutes befor e a second calibr ation is initi-
ated.
15
GENERAL MONITORS
Model S104
