Detcon FP-700 - Program Mode

Model FP-700
FP-700 Instruction Manual Rev. 5.1 Page 20 of 46
c) Apply the span calibration test gas at a flow rate of 200-500cc/min (200cc/min is the recommended flow
rate). As the sensor signal begins to increase, the display will switch to reporting a flashing “XX” reading
as the ITM shows the sensor’s “as found” response to the span gas presented. If it fails to meet the minimum
in-range signal change criteria within 2½ minutes, the display will report “Range Fault” twice and the ITM
will return to normal operation, aborting the AutoSpan sequence. The ITM will continue to report a “Range
Fault” and will not clear the fault until a successful AutoSpan is completed.
NOTE: Check response time by confirming that the reading comes onto scale in first 5 seconds and reaches
approximately 50% of the applied gas within 10-15 seconds and reaches approximately 90% of the applied gas
in 30-40 seconds.
After about 1 minute the reading will auto-adjust to the programmed AutoSpan level. For about another 30
seconds the AutoSpan sequence checks the sensor for acceptable reading stability. If the sensor fails the stability
check, the reading is re-adjusted back to the AutoSpan level and the cycle repeats until the stability check is
passed. Up to three additional 30-second stability check periods are allowed before the unit reports a “Stability
Fault” twice and the ITM will return to normal operation, aborting the AutoSpan sequence. The ITM will
continue to report a “Stability Fault” and will not clear the fault until a successful AutoSpan is completed.
If the sensor passes the stability check, the ITM reports a series of messages:
“AutoSpan Complete”
“Sensor Life XXX%”
“Remove Span Gas”
d) Remove the span gas and calibration adapter. The ITM will report a live reading as it clears toward “0”.
When the reading clears below the threshold of 5% LEL (100% LEL range) or 2% LEL (50% LEL range),
the ITM will display “Span Complete” and will revert to normal operation. If the sensor fails to clear to less
than the threshold within 5 minutes, a “Clearing Fault” will be reported twice and the ITM will return to
normal operation, aborting the AutoSpan sequence. The ITM will continue to report a “Clearing Fault” and
will not clear the fault until a successful AutoSpan is completed.
NOTE 1: If the sensor fails the minimum signal change criteria, a “Range Fault” will be
declared and a “Fault Detected” message will be displayed alternately with the sensor’s current
reading. The 4-20mA output will be taken to 0mA and the “Range Fault” fault bit will be set on
the Modbus output.
NOTE 2: If the sensor fails the stability criteria, a “Stability Fault” will be declared and a “Fault
Detected” message will be displayed alternately with the sensor’s current reading. The 4-20mA
output will be taken to 0mA and the “Stability Fault” fault bit will be set on the Modbus output.
NOTE 3: If the sensor fails the clearing time criteria, a “Clearing Fault” will be declared and a
“Fault Detected” message will be displayed alternately with the sensor’s current reading. The 4-
20mA output will be taken to 0mA and the “Clearing Fault” fault bit will be set on the Modbus
output.
3.5 Program Mode
Program Mode provides a View Sensor Status menu to check operational and configuration parameters.
Program Mode also provides for adjustment of the AutoSpan Level, Bridge Voltage, Gas Factor, Cal Factor,
and Serial ID. Additionally, it includes the Restore Factory Defaults and Signal Output Check diagnostic
functions.