( )
ADT672
ADT672
for
(
)
.
.
( )
( )
max/min
calibration has same
2 The abbreviated words of the ADT672:
The pressure measured by HART transmitter
The pressure measured by calibrator
.
The analog output current value set by HART transmitter.
The current value measured by calibrator
.
It is the rated pressure
the sensor in transmitter Over pressure may cause damage .
The rated range in HART transmitter (Lower limit is corresponding to 4mA, higher limit is corresponding to 20mA)
The actual range used in HART transmitter (Lower limit is corresponding to 4mA, higher limit is to 20mA)
3 HART function's serial number is displaying in the status area, as is function 1.
4 As figure 4-5, HART pressure transmitter includes: PV calibration and AO calibration.
The calibration is between PV and AO. Supply the pressure to transmitter. The
pressure is same as the higher/lower limit of transmitter. The actual pressure will have a linear relationship
with the current range (4~20mA) of AO. The PV
function as the pushbutton
【SPAN】&【ZERO】 calibration in the transmitter.
The calibration is between AO and CA (4~20mA). The transmitter outputs 4mA & 20mA, the CA
value measured by calibrator is sent to the zero register and span register. Then, AO output
value is approximating same as the CA measure value.
Example: The actual range of HART transmitter is 0~16kPa, current output is 4~20mA, 0.1%FS accuracy.
PV (Primary variable):
CP (Calibrator pressure):
AO (Analog output):
CA (Calibrator amp):
Sensor range:
PV range:
Actual range:
PV calibration:
AO calibration:
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