Det-Tronics U9500 Infiniti Gas Transmitter User Manual

Page 34

95-8444

10.1

Electrochemical Sensor Cell Replacement
For sensors with replaceable sensor cells (toxic and

oxygen sensors), it may not be necessary to replace

the entire sensor housing assembly when the sensor is

defective. Follow the procedure below to replace the

sensor cell.

1. Remove power to the transmitter prior to replacing

the sensor cell.

2. Remove the cap from the sensor base. See Figure

20. (There is no need to remove the sensor housing

from the junction box for this operation).

NOTE

Compare part numbers to be sure that the correct
replacement cell is being used.

3. Remove the old sensor cell. The sensor cell contains

a small amount of lead – dispose of properly. Check

for corrosion or contamination on the terminals of the

sensor base, and clean if necessary.

4. Determine proper orientation for the new cell, then

carefully

plug it in.

NOTE

Handle the sensor cell carefully. To avoid
possible damage, observe the normally accepted
procedures for handling electrostatic sensitive
devices. See form 75-1005 for additional
information.

5. Be sure that the O-ring on the sensor housing is

in good condition, then place the cap back on the

sensor base. Tighten only until snug. Do not over

tighten.

6. Re-apply power. Allow time for the unit to warm

up and stabilize (approximately one hour for best

results), then calibrate.

An adequate supply of spare electrochemical cell

assemblies should be kept on hand for field replacement.

For maximum protection against contamination and

deterioration, they should not be removed from the

original protective packaging until the time of installation.

To ensure maximum storage life, electrochemical cells

should be stored in the unopened bag that the sensor

is shipped in, at a temperature between 32°F and 68°F

(0 to 20°C) and a relative humidity between 15 and 90

percent.

B1203

SENSOR HOUSING

SENSING ELEMENT ASSEMBLY

CAP

HYDROPHOBIC FILTER

NOTE: SENSOR APPEARANCE MAY VARY

SLIGHTLY DEPENDING UPON MODEL.

Figure 20—Electrochemical Sensor Parts Identification