Page 70
ST 800 Series HART/DE Option User’s Manual
Revision 5.0
7 HART Calibration
7.1 About This Section
This section provides information about calibrating a Transmitter’s analog output and measurement
range. It also covers the procedure to reset calibration to the default values as a quick alternative to
measurement range calibration.
This section includes the following topics:
•
How to calibrate a Transmitter’s analog output circuit using the Communicator
•
How to perform a two-point calibration of a Transmitter
•
How to perform a correct reset to return a Transmitter calibration to its default values.
About Calibration
The ST 800 SmartLine Transmitter does not require calibration at periodic intervals to maintain
accuracy. If a recalibration is required, we recommend that perform a bench calibration with the
Transmitter removed from the process and located in a controlled environment to get the best
accuracy.
For Dual / Triple Calibration see page 75
Before you recalibrate a Transmitter’s measurement range, you must calibrate its analog output
signal. See section 6.10 for the procedure.
You can also use the FDC application to reset the calibration data to default values, if they are
corrupted, until the Transmitter can be recalibrated. See Section 6.8 for details.
All procedures in this manual assume the Transmitter is configured for Loop Current
Mode enabled).
Equipment Required
Depending on the selected calibration, you may need any of the following test equipment items to
accurately calibrate the Transmitter:
•
Digital Voltmeter or millimeter with 0.02% accuracy or better
•
MC Toolkit Calibration standard pressure source with a 0.02% accuracy
•
250 ohm resistor with 0.01% tolerance or better.
