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3 causes of abnormal measured values, 3 causes of abnormal measured values -5 – Yokogawa PH72 Personal pH/ORP Meter User Manual

Page 62

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IM 12B03D02-01E

7-5

7. Troubleshooting

(5) Err5

Out of temperature measuring range

Appears during measurement.

With the Model PH72 Personal pH/ORP Meter, a general-purpose sensor can be used in
the temperature range of 0 to 80

؇C and a needle type or test tube size sensor in the

temperature range of 0 to 100

؇C. If the operating temperature is significantly outside this

measuring range (below -10.0

؇C or above 120؇C), an Err5 message will appear.

Possible Cause:

• Operating temperature is significantly outside the measuring range.

Corrective Action:

• Adjust the temperature of the solution so it falls within the measuring range (0 to

80

؇C for general purpose types and 0 to 100؇C for needle type or test tube size

sensor).

(6) Err6

Meter electronics failure

Possible Cause:

• Failure of electronics.

Corrective Action:

• Contact your nearest Yokogawa sales office.

7.3 Causes of Abnormal Measured Values

If error messages do not occur, but measured values seem incorrect, check the following:

• Are proper standard solutions used?

• Is the sensor connected to the meter securely?

• Are air bubbles trapped in the electrode tip?

• Has the electrode dried out?

• Is the electrode dirty?

• Is the sensor damaged or dirty?

• Is the electrode immersed in the sample solution properly?

• Has the level of the electrode filling solution dropped (for KCl refillable type

sensors)?

• Is the electrode filling solution contaminated with the sample solution (for KCl

refillable type sensors)?

• Has the actual temperature of the solution been set properly (for a needle type or

test tube size pH sensor)?