Honeywell STT850 Series, Руководство пользователя

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Revision 4.0
STT850 Series HART/DE Option User’s Manual
Page 79
7.3 Calibrating Analog Inputs
The STT850 SmartLine Temperature Transmitter supports two-point input calibration. This means
that when two points in a range are calibrated, all points in that range adjust to the calibration.
LRV and the URV should always be calibrated both at the same time.
This procedure assumes that the Transmitter has been removed from the process and is located in a
controlled environment.
IMPORTANT! You must have a precision calibrator source with an accuracy of 0.02%
or better to do an input calibration. Note that the factory calibrates STT850 SmartLine
Temperature Transmitters temperature in deg C.
7.3.1 Correcting the Lower Range Value (LRV)
1.
Check that the Write Protect Jumper is in the “OFF” position.
2. See Figure 6 for typical test connections. Connect the power supply and communicator to the
signal terminals of the Transmitter terminal block..
3. Connect the precision calibrator source to the sensor (to be corrected) inputs of the
transmitter.
4. Turn on the power supply, and allow the Transmitter to become stable.
5. Turn the MC Toolkit on, start the FDC application.
6. On the FDC Home page, select Online, and establish communication with the Transmitter.
7. Check that the device is not in the Write Protect mode.
8. The Lower Calibration Point and Upper Calibration Point values have to be entered in the
respective sensor config parameters in the Sensors menu.
These calibration points are used in
the LRV Correct and URV Correct methods (not LRV and URV).
9. Select the My Device menu, and choose from the following selections:
a. Device Setup \ Calibration \ Calibration Methods \ Sensor (1 or 2) LRV Correct
10. You will be prompted to remove the loop from automatic control. After removing the loop
from automatic control, press OK.
11. When prompted, adjust the temperature source to apply value equal to the Lower Calibration
Point, and press OK.
12. When the temperature stabilizes, wait for 5 seconds, then press OK.
13. When prompted, remove temperature.
14. On the next prompt – “Please enter Calibration Date in MM/DD/YYYY format. Enter the
Calibration date (for example “05/27/2009”) and press Enter.
15.
On the next prompt - "Please enter the current calibration time in 24 Hr format (Hours
Field)", enter the Hours field HH (for example, "12"), and press ENTER
16. On the next prompt – “Please enter current Calibration Time (Minute field),” enter the
Minutes field MM (for example “23”), and press ENTER.
17. When prompted to return the loop to automatic control, press ENTER
NOTE: If you are calibrating LRV and URV at the same time do not power down and start up
again after the LRV steps, just go to step 1 of the URV procedure below.