Final Value As Valve Reference Value; Valve Position - Pepperl+Fuchs FieldConnex F2D0-MIO-Ex12.FF Series Manual

Multi-Input/Output Device
Parameterization and Operation
4.5.10

Final Value as Valve Reference Value

The reference value for the valve position and the associated status are issued in the Final
Value parameter. The Final Value is a copy of the OUT_D value of the DO function block
connected with the transducer block. This reference value can assume the values "closed" (0)
or "open" ( 0).
The value is accepted only with a status GOOD-NonCascade or GOOD-Cascade. If the status
is BAD or UNCERTAIN, the connected auxiliary valve is not controlled electrically, so that the
associated drive moves into the mechanical safety position.
4.5.11

Valve Position

The signals recorded by a connected final position feedback contact are indicated in several
parameters of different significance.
Sensor Value A or Sensor Value B Parameter
These parameters display the input signal of final position feedback contact A or final position
feedback contact B. The MIO device interprets a final position feedback contact signal as
follows: 
high current => logical 1 
low current => logical 0
Valve Position Parameter
The current valve position "open", "intermediate", or "closed" is displayed as value. By setting
the Sensor Usage parameter accordingly, the signals of the final position feedback contacts
are assigned a definite position.
For more information, see chapter 4.5.3.
Valve Position Extended Parameter
In the intermediate valve position, the information in the valve position parameter is extended
by the information "opening" and "closing". This information is determined by the current
control process and need not coincide with the actual direction of travel - i. e., when changing
the set position while the valve is in the intermediate position.
Primary Value Parameter
This parameter issues the value which is fed back as valve position to the assigned function
block. The Primary Value parameter is an unsigned 8 with the status which is displayed in the
function block as READBACK_D. Which information is issued at which value range in the
Primary Value parameter depends on how you set the Sensor Usage and PV_D Generation
parameters.
For more information, see chapter 4.5.3.
Valve Info Parameter
This parameter displays information of the current status of the valve or transducer block. This
includes the following information:
Stroke counter limit exceeded
■
Cyclic function test running
■
Actuation - The valve has not yet reached the new final position after having changed the
■
reference value.
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