Detcon FP-524D-HRT - Manual (Page 39)

Model FP-524D-HRT
FP-524D-HRT Instruction Manual Rev. 0.1 Page 35 of 48
6. The procedure will prompt to apply span gas. Apply span gas from the attached cal gas cylinder and
respond to the prompt.
NOTE: The sensor reading will respond to the gas and will switch to displaying a flashing
“XX”.
NOTE: Assuming acceptable sensor signal change, after 1 minute the reading will auto-adjust
to the programmed Auto Span level. During the next 30 seconds, the Auto Span sequence
checks the sensor for acceptable reading stability. If the sensor fails the stability check, the
reading is re-adjusted back to the Auto Span 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 sensor will return to normal operation, aborting the
Auto Span sequence. The sensor will continue to report a “Stability Fault” and will not clear
the fault until a successful Auto Span is completed.
7. If the sensor passes the stability check, the sensor reports a series of messages:
“AutoSpan Complete”
“Sensor Life XXX%”
“Remove Span Gas”
8. When the sensor passes calibration the procedure will prompt to remove the span gas. Unsuccessful
completion of the span calibration will create a Global Fault, and “Autospan Cal” will be aborted with a
change to the HART Sensor Status (refer to section 4.4.2.2 Sensor Status).
9. After successfully setting span cal the sensor and the HART Interface will return to Automatic Mode.
10. The Auto Span Calibration is complete
11. Remove the cal gas and calibration adapter if applicable.
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 on the sensor with the
current reading. The HART Sensor Status will change to reflect a Range Fault.
NOTE 2: If the sensor fails the stability criteria, a “Stability Fault” will be declared and a
“Fault Detected” message will be displayed alternately on the sensor with the current reading.
The HART Sensor Status will change to reflect a Sensor Fault.
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 on the sensor with the current
reading. The HART Sensor Status will change to reflect a Clearing Fault.
4.4.3.4 Loop Test Calibrate
The Calibration Screen contains a Loop Test Calibration section. This section displays the loop current
reading and allows the user to perform D/A trim and Loop Test. D/A trim is used to calibrate the 4mA and
20mA set points in the Digital/Analog converter. Loop test allows the user to set the mA output to any level
within range; this can be a good troubleshooting tool for line degradation.
A DVM capable of reading
milliamps and a 100~250 Ohm resistor are required to perform D/A trim and/or Loop test.