Emerson Process Management OXYMITTER 4000 - Manual (Page 107)

Instruction Manual
IB-106-340C Rev. 4.1
July 2004
Rosemount Analytical Inc. A Division of Emerson Process Management Troubleshooting 8-11
Hazardous Area 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
37260025
Alarms
Board Temp Hi
Figure 8-9. Fault 7, High Case Temp
g. Fault 7, High Case Temp
Figure 8-9 shows the electronic assembly
for a Hazardous Area Oxymitter 4000 with
a membrane keypad (upper view) and a
Hazardous Area Oxymitter 4000 with an
LOI (lower view).
Membrane Keypad. When Fault 7 is
detected, The HEATER LED flashes three
times, pauses for three seconds, and
repeats.
1. If the case temperature exceeds 85°C
(185°F), 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 Hazardous Area Oxymitter
4000 is installed exceeds the ambient
temperature requirements or that heat
due to convection is causing case tem-
perature to rise above the limit.
3. Placing a spool piece between the
stack flange and the Hazardous Area
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
displays the “Board Temp Hi” message.
Refer to the comments in paragraphs 1
through 4 above.
8