Hach Ultra ORBISPHERE 3624, Руководство оператора

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78 of 96 Maintenance and Troubleshooting - 3624 ProBrix Plus
Operator Manual
ORBISPHERE
8.1.5 Yearly
The following is available from Hach Ultra as a Maintenance Agreement:
• Replace membrane on the CO
2
sensor and recalibrate (refer to the accompanying
TC Sensor Maintenance and Installation Manual
for membrane replacement
instructions)
• Inspect pump for signs of wear (severe leakage) and perform pump seal
replacement if necessary (see “Pump Seal Replacement” on page 79 )
• Inspect O-rings in the flow chamber for wear, and replace if necessary
• Replace liquid detector at inlet of the ProBrix
Note:
CiP should be carried out any time the sample path is exposed to air.
8.2 Sensor Maintenance
It is time to perform an O
2
sensor service when you experience:
• Difficulties with calibration
• An unusually long stabilization time, either with the sensor exposed to an air-
saturated medium or to changing oxygen concentration conditions
• Noisy or drifting signals under what you believe to be constant oxygen
concentration conditions
For more information on O
2
sensor maintenance, please refer to the accompanying
EC
Sensor Maintenance and Installation Manual
Unlike your O
2
sensor, the CO
2
sensor does not require regular servicing. Membrane
changes need be performed far less often.
Periodically, check the CO
2
sensor calibration using a known standard. As long as the
reading is ±1% of the expected value, no action needs to be taken. If the reading has
changed ±1-10%, a new calibration should be performed. If the deviation is more than
10% of the original values, a membrane service is required.
A visual inspection of the sensor face will also reveal any problem like dust deposits or
accumulation of dirt onto the protection grill.
For more information on CO
2
sensor maintenance, please refer to the accompanying
TC
Sensor Maintenance and Installation Manual