AMI Analyzer Manual
Installation and Operation
••••
11
Verify Span Factor:
The analyzer features a “Span Factor” display to help you determine the state of the sensor. As the sensor ages, its
output decreases gradually, and therefore the span factor has to be turned up during calibration to compensate.
Press and release the UP button while the unit is showing its reading to view the span factor. The factor corresponds to
the setting of a traditional ten turn span pot with a turns counter dial on it.
The setting should be between 300 and 600 for a new sensor. When you calibrate the analyzer, check this value before
and after the calibration. You should see that the value goes up slowly over the life of the sensor. When the value has
gotten up to 1000, the sensor has reached the end of its life and should be replaced. Also, if the value suddenly jumps,
it indicates that the sensor is getting close to the end of its life.
Read the Temperature:
Press the DOWN arrow button. The display will show the temperature of the cell block in degrees Fahrenheit. The
value is limited to 25F at the lowest, and about 120F at the highest. Values outside this range will damage the sensor
Alarm Functionality:
The model 201LC series has two alarms, with two associated relays. Normally, these are set to operate as high alarms
(they go into alarm if the oxygen level goes above the set point), and to close their associated relays upon alarm. Their
time delay is set to zero, and they do not latch (unless specifically requested otherwise). An Alarm state is indicated by
the word “ALARM” appearing on the display.
Using the analyzer front panel you can change the alarm set points, but you cannot change any of the other settings. If
you want them to operate below alarm set point, to latch, or to operate in a pulse mode, you have to order the analyzer
set up that way. In this case contact the factory.
