WPI APOLLO 4000, Instruction Manual

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APOLLO 4000
TROUBLESHOOTING
WORLD PRECISION INSTRUMENTS F-1
Problem Solution
a) If the membrane sleeve has just been
changed, this is normal. Refer to the section
“Replacing a Membrane Sleeve.”
b) The membrane may be damaged. Replace
the membrane sleeve.
c) The electrode has just been attached to the
Apollo 4000. This is normal.
1) The current reads too high or offscale on the
display.
Troubleshooting for APOLLO 4000
a) Make certain that the contents of the
solutions used in the calibration procedure
are correct.
b) The membrane may be heavily
contaminated. Clean the membrane as
described in the section, “Cleaning the
Membrane.”
c) The electrolyte inside the sleeve may no
longer be functioning. Refer to the procedure
“Replacing a Membrane Sleeve”.
d) Open circuit in cable. Check cable
connections.
2) The sensor is unresponsive; current is close
to zero and/or there is no response to NO/
HPO/O
2
during calibration.
a) Make sure that the experimental set up is well
grounded and shielded as outlined in the
appendix on “Grounding and Shielding”.
b) Check that the electrode has not been
damaged. If it has, replace the sleeve or fit a
new sensor.
3) The baseline is noisy and/or drifts.