Det-Tronics U9500 Infiniti Gas Transmitter - Manual (Page 34)

95-8444 32 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