ABB XSeries G4 6200, Руководство пользователя, Страница: 128 / 168

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4) Click inside the Range window, and enter a range. The range can be
anything and represent any units (percent, volts, etc.) that the user prefers.
Target values will be updated to reflect the new calibration range.
5) Click on the Low Cal Point button, and apply the voltage (typically 1 volt) for
the low calibration point. Verify the current reading on the Enter Low
Calibration Value screen is stable.
6) Enter the Target value for the Low Cal Point, and click the OK button.
7) Click on the 100% Cal Point button, apply the voltage (typically 5 volts) that
represents the full range and verify the current reading is stable.
8) Enter the Target value for the 100% Cal Point, and click the OK button.
9) Click on the next highest Cal Point button, and apply a voltage representing
its range. Verify the current reading is stable.
10) Enter the Target value for that Cal Point, and click the OK button.
11) Repeat Steps 9 - 10 for any remaining Cal Points. After the last point is
entered, PCCU32 will automatically calibrate the AI.
4.16.2 Calibrating RTD temperature bias
If the user elects to use Bias as a calibration method, select Bias from the
Calibration drop-down menu.
To change, click in the Bias parameter field. The RTD Bias dialog box will display.
This allows the user to enter a new value. The RTD's temperature will always be
biased by this value; however, the RTD Installed box on the Setup tab must be
checked for the RTD temperature and bias to be used. If the bias needs to be
negative, enter a minus sign (-) before the value. The current temperature value
under the Tf heading will increase or decrease to reflect the effect of the bias. The
bias does not affect the Fixed Temperature that is specified on the Setup tab. The
user can select Sp, Dp, etc., in the drop-down Calibration window to return to the
selected Calibration screen.
4.17 Changing the orifice plate
Use one of the following procedures when changing the orifice plate:
4.17.1 Taking meter run out of service (simplex fitting)
1) Take the meter run out of service.
2) Replace the physical orifice plate.
3) If the user wants to end the current log record and begin a new record with
the new orifice size (as stated in API21.1), they need to first move into Entry
mode within PCCU32. Next, select the preferred measurement tube, and
then click on the Commands tab. Change the value for the Reset Log
Period to Yes. This forces a new record to be written based on the old
orifice plate size. Additionally, if the user wants to simultaneously zero the
accumulated volume, they can use the Reset Volume command instead.
It is recommended to perform either the Reset Log Period or the Reset
Volume command to enhance the audit trail created by the event (API 21.1
requirement).
4) In PCCU32, enter the new orifice plate diameter.
5) Return the meter to service.