Teledyne BDS-3000 - Oxygen analyzer - Manual (Page 72)

Operation BDS 3000
Teledyne Analytical Instruments 58
4.6.1 Setting the Analog Output Ranges
To set the ranges, enter the range function mode by pressing the
RANGE button on the front panel.
L—100 ppb M—1 ppm
H—10 ppm Mode—AUTO
Use the __arrow keys to blink the range to be set: low (L), medium
(M), or high (H).
Use the __ arrow keys to enter the upper value of the range (all
ranges begin at 0). Repeat for each range you want to set. Press ENTER
to accept the values and return to Analyze mode. (See note below.)
Note: The ranges must sequentially increase from low to high, for
example, if range 1 is set as 0–500 ppb and range 2 is set
as 0–10 ppm, range 3 cannot be set as 0– 5 ppm since it is
lower than range 2.
Ranges, and alarms, are set in ppb or ppm units depending on
concentration. All concentration-data outputs change from ppb units to
ppm when the concentration is above 1.0 ppm. Range Low (L) is always
a ppb range and cannot be set higher than 1000 ppb nor lower than 10
ppb. The medium (M) and High (H) ranges can only be set in ppm. The
Medium (M) range can be set between 1 and 10 ppm, while the high (H)
range can be set between 10 and 1000 ppm.
Note: Refer to Section 4.3.9 to find maximum working range.
4.6.2 Fixed Range Analysis
The autoranging mode of the instrument can be overridden, forcing
the analyzer DC outputs to stay in a single predetermined range.
To switch from autoranging to fixed range analysis, enter the range
function by pressing the RANGE button on the front panel.
Use the __ arrow keys to move the blinking over AUTO .
Use the __ arrow keys to switch from AUTO to FX/L , FX/M , or
FX/H to set the instrument on the desired fixed range (low, medium, or
high).