Emerson Rosemount Oxymitter 4000 Instruction Manual page 111

Instruction Manual
IM-106-340, Rev. 4.3
July 2017
Figure 8-15. Fault 13, Invalid Slope
DIAGNOSTIC
CALIBRATION RECOMMENDED
HIGH
HEATER
CALIBRATION
TP2
LOW
KEYPAD
Oxymitter 4000
Fault 13, Invalid Slope
Figure 8-15 shows the electronic assembly for
an Oxymitter 4000 with a membrane keypad
(upper view) and an Oxymitter 4000 with an LOI
(lower view).
Membrane Keypad
When Fault 13 is detected, the CALIBRATION
LED flashes once, pauses for three seconds,
and repeats.
1. During a calibration, the electronics
calculates a slope value. If the value of the
slope is less than 35 mV/dec or more than
52 mV/dec, the slope alarm will be active
until the end of the purge cycle.
2. See "Calibration with Keypad" in Section 9:
Maintenance and Service. Verify the
calibration by carefully repeating it. Ensure
the calibration gases match the calibration
gas parameters. If you attach a multimeter
to TP1+ and TP2-, sample gas
measurements are:
.
8% O 23 mV
2
.
0.4% O 85 mV
2
3. Power down the Oxymitter 4000 and
remove it from the stack.
4. Replace the cell per "Cell Replacement" in
Section 9: Maintenance and Service.
LOI
When Fault 13 is detected, the LOI displays the
"O2 Cell Bad" message. Refer to the comments
and procedures in paragraphs 1 through 4
above.
8-19