Figure 8-11. Fault 9, High Heater Temp - Emerson Oxymitter 4000 Instruction Manual

Oxymitter 4000
DIAGNOSTIC
ALARMS
CALIBRATION RECOMMENDED
TEST
POINTS
INC INC
HIGH LOW
GAS GAS
DEC DEC
KEYPAD
Alarms
O2 Temp Hi

Figure 8-11. Fault 9, High Heater Temp

Rosemount Analytical Inc. A Division of Emerson Process Management
HEATER T/C
HEATER
SW2
O2 CELL
CALIBRATION
J1
O2 CELL mV +
TP1
O2 CELL mv -
TP2
HEATER T/C +
TP3
HEATER T/C -
TP4
CAL
TEST GAS + TP5
PROCESS -
TP6
% O2
LOI
37260027
i. Fault 9, High Heater Temp
Figure 8-11 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 9 is de-
tected, the HEATER LED flashes five times,
pauses for three seconds, and repeats.
1. If the thermocouple produces a voltage
in excess of approximately 30.7 mV,
the high heater temp alarm activates.
2. The 4-20 mA signal returns to the de-
fault value (4 or 20 mA).
3. This alarm is self-clearing. When tem-
perature control is restored and the
thermocouple voltage returns to the
normal range, the alarm clears.
4. If the temperature continues to rise, the
next alarm will be the high high heater
temp alarm.
LOI. When Fault 9 is detected, the LOI dis-
plays the "O2 Temp Hi" message. Refer to
the comments and procedures in para-
graphs 1 through 4 above.
Instruction Manual
IB-106-340 Rev. 3.0
December 2003
Troubleshooting 8-13