Detcon FP-524HT User Manual
Page 15
b)
Next, scroll to the
“SET CAL FACTOR”
listing and then hold the programming magnet over “PGM 1” for 3
seconds. The menu item appears as
“CAL FACTOR #.##”.
Use the programming magnet to make an adjust-
ment to “PGM 1” to increase or “PGM 2” to decrease the display reading until the reading is equal to the
desired K factor. Save value by holding the programming magnet over “PGM1” for 3 seconds.
c)
Exit back to normal operations by holding the programming magnet over “PGM 2” for 3 seconds, or automati-
cally return to normal operation in 30 seconds.
3.8 C
ALIBRATION
Material Requirements
*
Detcon PN 3270 MicroSafe™ Programming Magnet
*
Detcon PN 612-0100000-700 Splashguard with Cal Port
*
Detcon PN 600-003427-000 FP-High Temp Splashguard Adapter
*
Span Gas containing the applicable calibration gas in air (see section 3.7). Span gas concentration is recom-
mended at 50% of range (which is the factory default) at a controlled f low rate of 200 ml/min. Other concen-
trations can be used as long as they fall within 10% to 90% of range. See section 3.8.2 for details.
3.8.1 Calibration Procedure - Zero
NOTE: Before performing a zero calibration, be sure there is no background combustible gas present or be pre-
pared to apply a zero gas standard.
a)
Enter the calibration menu by holding the programming magnet stationary over “PGM 1” (see figure 7) for 3 sec-
onds until the display reads
“1-ZERO 2-SPAN”
, then withdraw the magnet. Note that the “CAL” LED is on.
b)
Next, enter the zero menu by holding the magnet stationary over “PGM 1” for 3 seconds until the display
reads:
“ZERO 0%”
, then withdraw the magnet. The sensor has now entered the auto zero mode. When it is
complete the display will read
“ZERO COMPLETE”
for 5 seconds and then return to the normal operations
menu,
“0 % LEL”.
NOTE 1: If the circuitry is unable to adjust the zero to the proper setting the sensor will enter a calibration
fault mode which will cause the display to alternate between the sensor’s current status reading and the calibra-
tion fault screen which appears as:
“CAL FAULT”
(see section 3.8.3).
NOTE 2: When a “cal fault” occurs, the sensor microprocessor retains its previous calibration references but
the 4-20 mA signal drops to 0 mA until the Fault is corrected.
Zero calibration is complete.
3.8.2 Calibration Procedure - Span
CAUTION: Verif ication of the correct calibration gas level setting and calibration span gas concentration is
required before “span” calibration. These two numbers must be equal.
Calibration consists of entering the calibration function and following the menu-displayed instructions. The display
will ask for the application of span gas in a specif ic concentration. This concentration is equal to the calibration gas
level setting. The factory default setting for span gas concentration is 50% LEL. In this instance, a span gas contain-
ing a concentration equal to 50% LEL is required. If a span gas containing 50% LEL is not available, other concen-
trations may be used as long as they fall within 10% to 90% of range. However, any alternate span gas concentra-
tion value must be programmed via the calibration gas level menu before proceeding with span calibration. Follow
the instructions below for span calibration.
a)
Verify the current calibration gas level setting as indicated by the programming status menu. To do this, follow
Model FP-524HT Combustible Gas Sensor PG.15