Nova-Tech pH-CON 700 - Manual (Page 25)

13. TROUBLESHOOTING GUIDE
PROBLEM CAUSE SOLUTION
No display Main power not switched
on. AC Adapter socket not
inserted properly. Switch on the power supply.
Re-insert AC Adapter.
“Ur” (Under
range)
“Or” (Over
range)
in primary or
secondary
display
Measured value is out
of range.
Electrode not connected.
Electrode clogged, dirty
or broken.
Meter not calibrated.
Wrong temp value. Check electrode is connected.
Clean or replace electrode.
Recalibrate the meter.
Confirm measurement condition.
Treat samples to bring within
meter measuring range.
Reset meter.
Slow
response Dirty electrode.
Temperature of sample is
changing. Clean the electrode.
Allow temperature to stabilize.
Meter not
responding to
key press Manual HOLD or Auto
HOLD is active.
Worn keypad.
Press to deactivate manual
HOLD. See Section 9.4 to disable
Auto Hold feature if enabled.
Contact Technical Service.
Invalid key; Button is not
functional in the current
operation mode. Press alternate key.
Select valid key depending on
current mode.
The conductivity calibration
standard is not within 40%
of expected value during
automatic calibration.
Ensure that the conductivity
electrode guard is attached.
Use fresh standard or use an
alternate calibration standard.
Secondary
display
continually
scrolls
The pH buffer is >1 pH unit
from the available pH
buffers remaining for
calibration. Use fresh standard or use an
alternate calibration standard.
Verify the USA or NIST buffer
selection. Check pH electrode.
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