AMI Analyzer Manual
Maintenance and troubleshooting
20
Analyzer reads zero
1.
Verify that the sensor is in the correct position, not upside down. If it is upside down, verify that the membrane has
not been punctured - i.e. there is no sign of electrolyte on the surface, and if not, put it back the right way up. If you
have left it this way for a while, it may take several hours to recover to a low reading.
2.
Verify that the cell block contacts are touching the sensor. Pull the sensor tab, and the contact should hold the sensor
with a gentle force. If not, the contacts may be bent. If they have been bent too much, remove the sensor and gently
bend them back so that they can again make contact.
3.
Make sure that the gold plated contact wires are clean. If not, gently clean them with a Q tip or an eraser. Do not
use an abrasive cleaner, as it will remove the gold plating.
4.
Check the output of the sensor with a DVM configured to measure current. Connect its leads to the two gold rings
on the back of the sensor - the center is ground. The output should be around 150 to 750 micro Amps in air. This
will take a few minutes to stabilize as the sensor consumes oxygen dissolved in its electrolyte. Replace the sensor if
it does not read this amount. See sensor replacement instructions under Maintenance.
No voltage or current output to recording device
1.
Verify that the output wires are properly stripped and connected.
2.
Verify the connections on the output terminal block.
3.
Verify that the output connections are not shorted all the way back to the recording device. Disconnect the wires
from the analyzer and use an ohmmeter to check for shorts or opens.
No output alarm indication
1.
Verify the alarm set points are correct - press the appropriate switch on the front panel, and check the displayed
reading on the LCD for correct setting.
2.
Verify that the connections on the terminal block are properly stripped and correct.
3.
Verify that the output connections are not shorted all the way back to the recording device. Disconnect the wires
from the analyzer and use an ohmmeter to check for shorts or opens.
Incorrect readings
1.
Verify that there are no leaks in the system.
2.
Verify that the span gas bottle is correctly marked by comparing its reading when the analyzer has been spanned on
air to what it actually says.
3.
If spanning on air, verify that the air source is free of water vapor (humid air will contain about 3% less oxygen than
expected, depending on temperature), and that bottle air does actually contain 20.9% oxygen. Manufactured air
often does not!
Still no correct operation
1.
Call AMI at 714 848 5533, and ask for Technical assistance.
2.
Or contact us by email at [email protected].
