Emerson OXYMITTER 4000 - Manual (Page 114)

Instruction Manual
IB-106-340 Rev. 3.0
December 2003
8-10 Troubleshooting Rosemount Analytical Inc. A Division of Emerson Process Management
Oxymitter 4000
LOI
KEYPAD
DIAGNOSTIC
ALARMS
TEST
POINTS
HEATER T/C
HEATER
O2 CELL
CALIBRATION
CALIBRATION RECOMMENDED
O2 CELL mV +
O2 CELL mv -
HEATER T/C +
HEATER T/C -
INC INC
DEC DEC
HIGH
GAS
LOW
GAS
CAL
TEST GAS +
PROCESS -
% O2
SW2
TP1
J1
TP2
TP3
RED YEL GRN ORG
TP4
TP5
TP6
ON
37260024
Alarms
Very Hi O2 Temp
Figure 8-8. Fault 6, High High Heater Temp
f. Fault 6, High High Heater Temp
Figure 8-8 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 6 is de-
tected, the HEATER LED flashes twice,
pauses for three seconds, and repeats.
1. The high high heater temp alarm will
activate when the thermocouple pro-
duces a voltage of 37.1 mV
(1652°F/900°C).
2. The triac and the temperature control
may be at fault.
3. Remove power. Allow the Oxymitter
4000 to cool for five minutes. Restore
power.
4. If the condition repeats, replace the
electronic assembly per paragraph 9-
4d, Electronic Assembly Replacement.
LOI. When Fault 6 is detected, the LOI dis-
plays the “Very Hi O2 Temp” message.
1. The very high O
2
temperature alarm
will activate when the thermocouple
produces a voltage of 37.1 mV
(1652°F/900°C).
2. The triac and the temperature control
may be at fault.
3. Remove power. Allow the Oxymitter
4000 to cool for five minutes. Restore
power.
4. If the condition repeats, replace the
electronic assembly per paragraph
9-4d, Electronic Assembly Replace-
ment.