GF Signet 2750 DryLoc pH_ORP Sensor Electronics User Manual
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Signet 2750 DryLoc pH/ORP Sensor Electronics
9. Troubleshooting
LED and Output Condition
Possible Causes
Suggested Solutions
Current Out:
LED off, current output is 3.6 mA
S
3
L: Temp out is +999.9
• No electrode installed.
• Bad/dirty contacts between electrode
and 2750.
• Install
electrode.
• Check interconnection between
electrode and 2750, clean contacts.
During EasyCal, the LED blinks rapidly
for 4 seconds and the current output is
frozen at a random fi xed value.
• The buffer solution is outside of the
accepted tolerance for the 2750.
• The electrode is depleted (> 1.1 pH or
65 mV offset).
• pH system: Use fresh 4 pH, 7 pH,
or 10 pH buffer and restart the
calibration.
• ORP system: Use fresh 4pH and
7 pH buffer solution saturated with
quinhydrone.
• Replace the electrode.
After completing calibration procedure,
the output values are inaccurate.
• Insuffi cient time allowed for electrode
stabilization during calibration.
• Recalibrate; verify that test solutions
are at room temperature and wait
at least 30 seconds after placing
electrode in solution before pressing
S1 EasyCal button.