Aalborg DPC, Руководство по эксплуатации

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NOTE: Relay terminals are accessible via the DPC controller’s 8-pin MiniDIN
connector (pins 1 and 2) and have maximum 48VDC voltage and 0.4A current
ratings. See Figure 3 and Table I for proper wiring connections.

6.4.15.7 Analog Output Confi guration
The DPC series Mass Flow Controllers are equipped with calibrated 0-5Vdc, 0-10Vdc, and
4-20 mA output signals. The following options are provided for analog output:
a) Analog Output Mode (Tabular entry)
The user can select one of the following:
  
0-5 Vdc (3000

minimum load impedance)
  
0-10 Vdc (5000

minimum load impedance)
  
4-20 mA (sourcing type, 500

maximum current loop resistance)
NOTE: Before changing “Analog Output Interface” mode, make sure the load
impedance is within the corresponding limits stated above. Failure to do so
might cause damage to the analog output circuitry or result in
erroneous
readings.

CAUTION: The 4-20 mA current loop output is self-powered (sourcing
non-isolated type). Do NOT connect an external voltage source to the output
signals. (See Section 3.3 for proper wiring connections.)

b) Analog Output Calibration
The DPC analog output calibration involves calculation and storing the offset and span
variables in the EEPROM based on two calibration points (0 and 100% F.S.). The 0-5
and 0-10 outputs have only scale variables, and the 4-20 mA output has offset and
scale variables.
NOTE: The analog outputs available in the DPC controller were calibrated at the
factory. There is no need to perform analog output calibration unless the analog
to digital converter (DAC) IC, output amplifi er IC, or passive components from
analog output circuitries were replaced or your factory customer support
representative suggested recalibration. Any alteration of the analog output
scaling variables in the EEPROM will void the calibration warranty supplied with
the
instrument.
