Teledyne T101, Operation Manual, Page: 96 / 375

Operating Instructions Teledyne ML – T101 Operation Manual
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4.6.3.4. Analog Output Offset Adjustment
Some analog signal recorders require that the zero signal is significantly different from
the baseline of the recorder in order to record slightly negative readings from noise
around the zero point. This can be achieved in the T101 by defining a zero offset, a small
voltage (e.g., 10% of span), which can be added to the signal of individual output
channels by activating the ANALOG I/O CONFIGURATION MENU (see Section 4.6.3),
then pressing:
DIAG AIO RECORD OFFSET: 0 MV
+ 0 0 0 0 ENTR EXIT
DIAG ANALOG I / O CONFIGURATION
PREV NEXT ENTR EXIT
DIAG AIO AOUTS CALIBRATED: NO
< SET SET> CAL EXIT
FROM ANALOG I/O CONFIGURATION MENU
DIAG AIO CONC_OUT_2 RANGE: 5V
SET> EDIT EXIT
Set the recorder
offset (in mV) of
the selected
channel
DIAG AIO CONC_OUT_2:5V, CAL
< SET SET> EDIT EXIT
DIAG AIO CONC_OUT_2 REC OFS: 0 mV
< SET SET> EDIT EXIT
Pressing ENTR accepts the
new setting and returns to the
previous menu.
Pressing EXIT ignores the new
setting and returns to the
previous menu.
Press SET> to select the
analog output channel to
be configured. Then press
EDIT to continue
4.6.3.5. Current Loop Output Adjustment
A current loop option is available and can be installed as a retrofit for each of the analog
outputs of the analyzer. This option converts the DC voltage analog output to a current
signal with 0-20 mA output current. The outputs can be scaled to any set of limits within
that 0-20 mA range. However, most current loop applications call for either 2-20 mA or
4-20 mA range. All current loop outputs have a +5% over-range. Ranges with the lower
limit set to more than 1 mA (e.g., 2-20 or 4-20 mA) also have a -5% under-range.
To switch an analog output from voltage to current loop after installing the current output
printed circuit assembly, follow the instructions in Section 4.6.3.1 and select curr from the
list of options on the “Output Range” menu.
Adjusting the signal zero and span values of the current loop output is done by raising or
lowering the voltage of the respective analog output. This proportionally raises or lowers
the current produced by the current loop option.