Figure 8-9. Fault 7, High Case Temp - Emerson Oxymitter 4000 Instruction Manual

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

Figure 8-9. Fault 7, High Case 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
37260025
g. Fault 7, High Case Temp
Figure 8-9 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 7 is de-
tected, The HEATER LED flashes three
times, pauses for three seconds, and re-
peats.
1. If the case temperature exceeds 185°F
(85°C), the temperature control will
shut off and the 4-20 mA signal output
will go to the default value.
2. This signifies that the environment
where the Oxymitter 4000 is installed
exceeds the ambient temperature re-
quirements or that heat due to convec-
tion is causing case temperature to rise
above the limit.
3. Placing a spool piece between the
stack flange and the Oxymitter 4000
flange may eliminate this problem.
4. If a spool piece does not solve the
problem, relocation is the only solution.
LOI. When Fault 7 is detected, the LOI dis-
plays the "Board Temp Hi" message. Refer
to the comments in paragraphs 1 through 4
above.
Instruction Manual
IB-106-340 Rev. 3.0
December 2003
Troubleshooting 8-11