Oxymitter 4000

 

HEATER T/C

 

DIAGNOSTIC

HEATER

SW2

ALARMS

O2 CELL

ON

 

 

CALIBRATION

 

CALIBRATION RECOMMENDED

Instruction Manual

IB-106-340 Rev. 3.0

December 2003

i. Fault 9, High Heater Temp

Figure 8-11shows 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,

TEST

POINTS

INC INC

HIGH LOW

GAS GAS

DEC DEC

O2 CELL mV +

O2 CELL mv - HEATER T/C + HEATER T/C -

CAL

TEST GAS + PROCESS - % O2

TP1 TP2 TP3 TP4

TP5 TP6

J1 RED YEL GRN ORG

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.

KEYPAD

Alarms

O2 Temp Hi

LOI

37260027

Figure 8-11. Fault 9, High Heater Temp

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 displays the “O2 Temp Hi” message. Refer to the comments and procedures in paragraphs 1 through 4 above.

Rosemount Analytical Inc. A Division of Emerson Process Management

Troubleshooting 8-13