Aalborg TIO, Руководство по эксплуатации, Страница: 42 / 98

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c) Flow Power Up Delay (Numerical entry)
Sometimes it is convenient to start the process input signals after the
specified power-up delay interval. Most mass flow meters and controllers
require some warm-up time from the power-up event in order to stabilize
process variable output and get accurate reading. “Flow Power
UP Delay”
option allows a set specified time interval which must elapse from the
device power-up event, before processing of the input signals will be
activated. During the active faze of the Power Up Delay, the flow rate will
be internally driven to zero and not totalized. Valid settings are in the
range of 0 to 3600 seconds (default value is 0, no delay).
d) Fluid Std. Density (Numerical entry)
The density of the flowing fluid at standard temperature and pressure
conditions must be entered in g/litr. This parameter is used only when
mass-based engineering units are selected. Valid settings are in the range
of 0.000001 to 10000.0 g/litr. Factory set default value is 1.25 g/litr
(Nitrogen).
e) Analog Output Calibration
The TIO analog output calibration involves calculation and storing the off
set and span variables in the EEPROM based on two calibration points (0
and 100% F.S.). The 0-5 (0-10)Vdc output has only scale variable and
4-20 mA output has offset and scale variables.
Power up the TIO instrument for at least 15 minutes prior to
commencing the calibration procedure. Observe analog output jumper
position (see Figure 4.2) and connect the corresponding type of
measurement device to pins 5 (plus) and 8 (minus) of the 9-pin
D-connector. Follow firmware prompts and adjust calibration point values
according to measurement device reading. If calibration must be aborted,
press
ESC button. When calibration is completed firmware will display
new offset and span values and ask the user to press the ENT button to
save new calibration variables to EEPROM or ESC to abort calibration and
exit without saving. In the end, the firmware will prompt with
confirmation message.
NOTE: The analog outputs available in the TIO were calibrated at
the factory. There is no need to perform analog output calibration
unless the DAC IC, output amplifier IC or passive components from
analog output circuitries were replaced. Any alteration of the analog
output scaling variables in the EEPROM table will VOID calibration
warranty supplied with the instrument.
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