4 Operation Model 3190
4-4 Teledyne Analytical Instruments
2. Within 5 seconds, press either the ∆ or ∇ button to raise or lower
the displayed value, as required, until the display reads the
desired concentration.
4.4.2 LO Alarm
Setting the LO Alarm sets the value BELOW which the LO alarm will
activate. To set the LO Alarm:
1. Press the SET LO ALARM Function button once.
2. Within 5 seconds, press either the ∆ or ∇ button to raise or lower
the displayed value, as required, until the display reads the
desired concentration.
4.4.3 Sensor Fail Alarm
The SENSOR FAIL alarm triggers if, during calibration, the raw cell
output for the given oxygen level is too low. (See Calibration
Characteristics in Chapter 2.) Should this alarm trigger, The ALARM
indicator below the SET function buttons will start blinking. Replace the cell
before proceeding.
4.5 Selecting a Fixed Range or Autoranging
The Model 3190 can operate in fixed high, fixed low, or autoranging
mode. To change modes:
1. Press and then release the SET HI RANGE and the SET LO
RANGE buttons simultaneously.
2. Within 5 seconds, press either the ∆ or ∇ button until Auto, Lo,
or Hi displays on the LCD, as desired.
After about three seconds, the analyzer resumes monitoring in the
selected range mode.
NOTE:If the concentration exceeds 9,999 ppm oxygen, the analyzer
will automatically switch to the Calibration Range, EVEN
THOUGH INSTRUMENT IS IN THE FIXED RANGE MODE.
4.6 Calibration
Preliminary—If not already done: Power up the Analyzer and
allow the LED reading to stabilize. Set the Alarm setpoints and
the fullscale ranges to the desired values.