Detcon FP-524HT User Manual

Page 15

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.

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.

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.

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.

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