The PID Function Block Operator Keyboard faceplate contains the following items:
PV bar graph – This graph indicates the value of the PV parameter for the block, which is the same as the value displayed in the PV field.
PV – This field displays the PV value of the PID block in yellow. The background color of the field changes from gray to orange or red when the PV status becomes uncertain or bad, respectively. The PV value is visible in the decimal format provided by PV_SCALE.DECPT.
Output bar graph – This field indicates the value of OUT_READBACK, which is the same as the value displayed in the OUT_READBACK field.
OUT_READBACK – This field displays the OUT_READBACK value of the PID block in cyan. The background color of the field changes from gray to orange or red when the Output status becomes uncertain or bad, respectively. In the absence of a configured IO_READBACK DST, the OUT_READBACK value shown is equal to the implied output value of the loop. The displayed decimal format of OUT_READBACK is determined by the OUT_SCALE.DECPT parameter field.
Output slew keys – These gray buttons with cyan arrowheads appear only when the loop has a target mode of MAN or OOS. Click the corresponding button to increment or decrement the output value by 1 or 10 engineering units.
MODE buttons – These buttons are used to set the target mode of the PID block. Only buttons for valid modes appear on the faceplate.
A gray outline appears around the button if the current mode is the normal mode and the target matches the normal mode. . If the target and actual modes do not match, the label on this button blinks. A blue outline appears around the button if the target mode does not match the normal mode, but the target mode matches the actual mode.
Setpoint bar graph – A bar graph, indicating the value that appears in the Setpoint field.
Setpoint – This field displays the Setpoint value of the block. The background color of this field changes from gray to orange or red when the PV status becomes uncertain or bad, respectively. The valid range for the SP value is from 0 to 100 percent of PV_SCALE. The SP value is visible in the decimal format provided by PV_SCALE.DECPT.
Setpoint slew keys – These gray buttons with white arrowheads appear only when the loop has a target mode of AUTO, MAN, or OOS. Click the corresponding button to increment or decrement the setpoint value by 1 or 10 engineering units.
Detail Display button – This button is used to open the detail display for the PID block.
Trend Display button – This button is used to open the trend display for the PID block. A trend display is a popup picture that shows a one second trend trace for each of the module's main operating parameters. The trend traces start when the picture is opened and stops when it is closed.
Module Faceplate button – This button is used to open the module faceplate display.