Honeywell STT850 Series, Руководство пользователя

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Page 66 STT
850 Series HART/DE Option User’s Manual
Revision 4.0
6. Select the Set button. You will be prompted to confirm that you want to put the Transmitter
in output mode.
7. Select Yes , and note the output current at 0%, 100% or the other value established in the
previous step. With the Transmitter in analog mode, you can observe the output on an
externally connected meter or on a display. In DE mode, the output can be observed on the
display or on the monitor display of the MC Toolkit.
8. To view the Monitor display, navigate back from the LOOP TEST display, and select the
MONITOR display. A confirmation prompt will be displayed for you to verify that you want
to change pages. Select
Yes .
6.5 Calibrating Range Using the MC Toolkit
The range calibration involves two procedures, one to calibrate the input, the other to calibrate the
output. This section provides both procedures.
6.6 Conditions for Input Calibration
Calibrate Transmitter input only when necessary, and under conditions that will ensure accuracy:

Take Transmitter out of service, and move it to an area with favorable environmental conditions, for
example, clean, dry, and temperature-controlled

The source for the input Temperature must be precise, and certified for correct operation.

Qualified personnel are required for the input calibration procedure.
To optimize accuracy, the PROM includes storage for calibration constants: Correct LRV, and
Correct URV. These constants provide for optimum accuracy in that they enable fine-tuning of the
input calculations by first correcting at zero input, then by bounding the input calculations at the
selected operating range. Corrections are applied at the Lower Range Value (LRV) and the Upper
Range Value (URV).