Inspecting The Sensor - Instrutech Hornet CCM502 User Manual

Instruction Manual

7.4.1 Inspecting the sensor

If the cause of the fault is suspected to be in the measuring chamber (sensor), the following checks can be made
with an ohmmeter.
Tools / Material Required
• Allen wrench AF 2
• Pliers for retaining ring
• Ohmmeter
3
2
1
 Unfasten the hexagon socket set screw (4) and remove the complete measuring chamber (3) from the
electronics unit (5).
 Remove the retaining ring (1) as well as the ionization chamber (2) from the measuring chamber (3).
 Check the ionization chamber and the measuring chamber for contamination:
• Ionization chamber is contaminated only: Replace ionization chamber.
• Measuring chamber is severely contaminated: Replace complete measuring chamber.
 Using an ohmmeter, make following measurements on the contact pins.
Measurement
between pins
5 + measuring
∞ <<∞
chamber
3
4
2
1
5
Replace measuring chamber if defective.
 It is recommend to perform a leak test (leak rate <1×10
InstruTech
5
4
Possible cause
Contamination,
short circuit
cold cathode
sensor
Measuring chamber
-9
mbar l/s).
CCM502 Hornet
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