YOKOGAWA ZR202S, User Manual, Page: 130 / 163

<11. Inspection and Maintenance>
11-1
IM 11M13A01-04E
11. Inspection and Maintenance
This chapter describes the inspection and maintenance procedures for the EXAxt ZR Zirconia Oxygen
Analyzer to maintain its measuring performance and normal operating conditions.
WARNING
When checking the detector, carefully observe the following:
• The instrument modification or parts replacement by other than authorized representative of
Yokogawa Electric Corporation is prohibited and will void ATEX Flameproof approval, Factory
Mutual Explosion-proof approval and Canadian Standards Explosion-proof certification.
• Do NOT touch the probe if it has been in operation immediately just before being checked.
( The sensor at the tip of the probe heats up to 750°C during operation. If you touch it, you will
get burned.)
CAUTION
• Do not subject the probe to shock or cool it rapidly.
The sensor is made of ceramic (zirconia). If the detector is dropped or bumped into something,
the sensor may be damaged and no longer work.
• Do not reuse a metal O-ring to seal the cell assembly. If you replace the cell or remove it from the
probe for checking, be sure to replace the metal O-ring. Otherwise, the furnace gas may leak,
and then the leaking corrosive gas will cause the built-in heater or thermocouple to disconnect,
or the detector may corrode.
• Before opening or closing the terminal box, first remove dust, sand, or the like from the terminal
box cover.