Teledyne Analytical Instruments 3020 M, Руководство по эксплуатации

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Operation Model 3020M-ATEX
Teledyne Analytical Instruments 56
corresponding shift in the DC percent-of-range output, and in the range
ID outputs, will be noticed.
The auto-ranging feature can be overridden so that analog output
stays on a fixed range regardless of the oxygen concentration detected. If
the concentration exceeds the upper limit of the range, the DC output
will saturate at 1 VDC (20 mA at the optional current output).
However, the digital readout and the RS-232 output of the
concentration are unaffected by the fixed range. They continue to read
accurately with full precision. See
Front Panel description in Chapter 1.
The automatic air calibration range is always 0-25 % and is not
programmable.
4.10.1 Setting the Analog Output Ranges
To set the ranges, ENTER the
RANGE
function mode by selecting
RANGE
from the MAIN MENU. The
RANGE
screen appears.
L—5.00 M—25.0
H—100.00 Mode—AUTO
Use the DOWN/UP control to the range to be set: low (
L
), medium
(
M
), or high (
H
).
Use the DOWN/UP switch to enter the upper value of the range (all
ranges begin at 0 ppm). Repeat for each range you want to set. ENTER
to accept the values and return to the
Analysis Mode . (See note below.)
Note: The ranges must be increasing from low to high, for
example, if range 1 is set as 0
–5% and range 2 is set as
0
–90 %, range 3 cannot be set as 0–50% since it is lower
than range 2.
4.10.2 Automatic Ranging
After defining your analysis ranges, set
Mode –
to
AUTO
, if not
already there. ESCAPE to re-enter the ANALYZE screen using the
fixed range.
4.10.3 Fixed Range Analysis
The auto-ranging mode of the instrument can be overridden,
forcing the analyzer DC outputs to stay in a single predetermined range.