Yokogawa Single Channel Oxygen Analyzer System ZR22/ZR402 - Manual (Page 172)

IM 11M13A01-02E 11-1
11. Inspection and Maintenance
11. Inspection and Maintenance
This chapter describes the inspection and maintenance procedures for the EXAxtZR
Zirconia Oxygen Analyzer to maintain its measuring performance and normal operating
conditions.
WARNING
When checking the detector, carefully observe the following:
(1) The instrument modification or parts replacement by other than authorized
representation of Yokogawa Electric Corporation is prohibited and will void ATEX
flameproof Certification, Factory Mutual Explosionproof approval and Canadian
Standards Explosionproof Certification.
(2) 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
Њ C during operation. If
you touch it, you will get burned.)
(3) 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.
(4) 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. Other-
wise, the furnace gas may leak, and then the leaking corrosive gas will cause the
built-in heater or thermocouple to go open circuit, or the detector may corrode.
(5) Before opening or closing the terminal box, first remove dust, sand, or the like from
the terminal box cover.