beautypg.com

Fault indications, Fault indications -2, Model 3081fg – Emerson 3081FG User Manual

Page 60: Instruction manual

background image

Instruction Manual

IB-106-3081 Rev. 1.5
September 2002

6-2 Troubleshooting

Rosemount Analytical Inc. A Division of Emerson Process Management

Model 3081FG

IMPEDANCE,

SPEED

OF

RESPONSE

(t

),

sec

90

0

26020060

100

200

300

400

500

AIR TO 0.4% O

2

0.4% O TO AIR

2

Figure 6-2. Speed of Response

Frequently conduct calibration checks to look for
the following conditions:

• Continued degradation of cell slope.

• Sluggish response. (Note how long it takes

the cell to respond to the application of cali-
bration check gases.) See Figure 6-2.

The slope will be valid only for the process tem-
perature at which the calibration check gases
are flowed, so no adjustments to the electronics
are made as a result of a calibration check.

Note that cells exposed to temperatures above
1300°C (2372°F) may lose the ability to meas-
ure accurately and respond quickly when re-
turned to the lowest end of the operating
temperature range [550°C (1022°F)].

6-3

FAULT INDICATIONS

The fault conditions for the Two-Wire In Situ
Oxygen Analyzer will be indicated by the faulted
operation display as shown in Figure 6-3. This
screen displays when a fault that invalidates the
O

2

reading is present. When the error is cor-

rected, the screen will return to a normal opera-
tion display unless another error exists.

%

mA

26020022

Figure 6-3. Faulted Operation Display