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8. Maintenance
This gas detector requires no on site gas calibration. Each sensor unit has been gas-calibrated
when shipped. Replace the sensor unit with a new one every 6 months except for combustible gas
sensor units (CHS-7). The CHS-7 is divided into two types, hot-wire combustible (CH) and
catalytic (CS). Sensor life of CH and CS types are 5 and 3 years from the installation date
respectively.
Routine checks are carried out by the user. 6-month and 3-year periodic inspections are
performed by the user, New Cosmos or its authorized representative.
Record check/inspection results and save them for at least 3 years. Example of the
check/inspection results is on page 39.
Inspection Contents and Frequency
Check item
Startup or
relocation
Periodic Inspection
Routine
check
Every 6 months
Every 3 years
(1) Concentration display
V
V
V
(2) Sampling gas flow rate
V
V
(3) Airtightness
V
V
(4) Filter element
V
(5) Tubing
V
(6) Sensor unit
installation/replacement
V
V
(7) Sampling unit replacement
V
(8) Loop check and alarm test
using TEST switch
V
V
Important Maintenance Notice
In order to ensure the reliability of the gas detector, it is vital to perform periodic sensor unit
replacement. The replacement can be done by the user, but it is highly recommended that a
maintenance contract with a local New Cosmos representative be made for the performance
of periodic sensor unit replacement and inspection.
