Crystal FastCalXP Calibration Software User Manual
Page 21
Calibrating Gauges
19
FastCalXP Operation Manual
To Match the Reference to the Target Pressure
1
Turn the handle of the GaugeCalHP until the Reference matches the Target Pressure.
2
Read the gauge and enter that value in the
Gauge box
.
The number you enter may be modifi ed based on the minor graduation or resolution of the gauge as it is specifi ed.
Transmitter Calibration
When performing transmitter calibration an nVision (with an MA20 module and a Pressure module installed) and/or HART modem is required, depending on
what type data needs to be collected. A 30 Series pressure calibrator may also be used in place of the nVision. The model defi nition for the gauge will defi ne
the requirements for the transmitter.
If the transmitter model includes milliamp output, then the reference must be an nVision or 30 Series pressure calibrator. If you are calibrating a smart trans-
mitter, a HART modem must be connected to the computer and the leads must be connected to the power leads of the smart transmitter. See
for a diagram of the correct electrical connections.
Note that while a HART modem is necessary to read the HART digital pressure signal from a smart transmitter, it is not required to calibrate this type of trans-
mitter if an nVision or 30 Series pressure calibrator is used as the reference. Also, it is not possible to change the digital signal without using a HART communi-
cator. The use of a HART communicator is not discussed in this manual.
The HART indicated pressure is acquired using the connected HART modem by querying the transmitter using the HART address information entered when
creating the gauge. FastCalXP also uses the mA low range value and mA high range value from the model information to compute the pressure from the
measured milliamps. Note that the milliamp pressure reading is computed from the measured milliamps and will most likely will not be the same value as the
HART pressure reading.