Ph/Orp Probe Check - Hanna Instruments HI504 Instruction Manual

pH/ORP PROBE CHECK

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The pH electrode and the reference electrode for both pH
and ORP can be automatically monitored through HI504 .
Setup items involved are I .13 (pH electrode impedance test
enable), I .14 (reference electrode impedance test enable),
I .15 (maximum reference electrode impedance) and I .04
(potential matching pin enable) .
A "pH electrode broken or leakage error" (error code:
10) is generated whenever the pH electrode impedance
is less than approximately 1 MΩ . This error can be due to
breakage of the electrode glass or short circuits caused by
moisture or dirt .
A "reference electrode broken or dirty or not immersed"
error (error code: 11) is generated whenever the reference
electrode impedance is greater than the value set in item
I .15 (maximum reference electrode impedance range is
0 .5 to 100 .0 KΩ, default is 50 .0 KΩ) . This error can be
due to soiling of the reference electrode . It can occur also
when either the reference electrode or the matching pin
are not immersed in the solution . An automatic cleaning
procedure can be triggered by this error (see the "Alarm -
Error configuration" section for more details) .
The pH electrode test is performed when the following
conditions are satisfied:
• the test has been enabled through the setup item I .13;
• the device is in one of the following modes: idle, last
calibration data scrolling, event log file scrolling;
• the device is not in hold mode;
• the device is configured to measure pH .
Note
If an amplified electrode is used, the pH electrode test
must be disabled through the setup item I.13.
The reference electrode test is performed when the following
conditions are satisfied:
• the matching pin has been enabled through the setup
item I .04;
• the test has been enabled through the setup item I .14;
• the device is in one of the following modes: idle, last
calibration data scrolling, event log file scrolling;
• the device is not in hold mode .
Note
When testing or calibrating the instrument through a
pH/ORP simulator like HI931001 or HI8427, tempo-
rarily set the items I.13 and I.04 to "OFF".