Maintenance
C A U T I O N
Multiple hazards. Only qualified personnel must conduct the tasks described in this
section of the document.
Clean the sensor
Clean the sensor when:
•
"SENSOR?" shows on the display
•
Stabilization is slow
•
Results drift or are not accurate
•
Calibration failure occurs
1.
Soak the sensor in the applicable cleaning agent. Refer to
.
2.
Rinse or soak the sensor in deionized water for 1 minute.
Table 3 Cleaning agents
Contaminant
Cleaning agent
Time
Grease, oils and fats
Electrode cleaning solution
2 hours maximum
Mineral buildup
10% hydrochloric acid (HCl) solution
5 minutes maximum
Replace the batteries
When the battery icon flashes or the tester will not come on, replace all four batteries.
Refer to
Replace the sensor
Note: Only Pocket Pro+ testers have replaceable sensors.
To replace the sensor, refer to the instructions supplied with the sensor.
Troubleshooting
Message
Possible cause
Solution
SENSOR?
The calibration slope is ±10–15%.
Gently clean the sensor. Refer to
on page 10.
ECAL
Calibration failure. The pH calibration
slope is greater than ±15%.
Gently clean the sensor. Refer to
on page 10. Calibrate again. If calibration failure continues,
replace the tester or sensor as applicable.
"- - - -"
(top line)
The parameter value is not within the
measurement range of the tester. Refer to
on page 2.
Make sure that the value of the sample is within the
measurement range of the tester. Gently clean the sensor.
Refer to
on page 10. Calibrate as
necessary.
"- - - -"
(bottom line)
The temperature value is not within the
operating temperature range of the tester
or a temperature sensor failure occurred.
Refer to
on page 2 for the
operating temperature range.
Make sure that the sample temperature is within the
operating temperature range of the tester. Contact
technical support as necessary.
Note: The tester can still be used if a temperature sensor failure
has occurred, but without automatic temperature compensation.
Battery icon
flashes
The batteries have less than 10% power
remaining.
Replace all four batteries. Refer to
on page 5.
10
