App-5 – Yokogawa YVP20S User Manual
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App-5
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TA01-5.EPS
The User Layer provides scheduling of Function Blocks (FBs), as well as Device Descriptions (DDs)
which allow the host system to communicate with devices without the need for custom programming.
VCR
See Virtual Communication Relationship
User Application
The User Application is based on “blocks,” including Resource Blocks (RBs), Function Blocks (FBs)
and Transducer Blocks (TBs), which represent different types of application functions.
User Layer
The full featured Yokogawa software for diagnostics, calibration, and configuration of Foundation
fieldbus positioner, YVP.
ValveNavi
A Virtual Field Device (VFD) is used to remotely view local device data described in the object
dictionary. A typical device will have at least two Virtual Field Devices (VFDs).
Virtual Field Device
(VFD)
Configured application layer channels that provide for the transfer of data between applications.
FOUNDATION fieldbus decribes three types of VCRs: Publisher/Subscriber, Client/Server, and
Source/Sink.
Virtual Communication
Relationship (VCR)
A Standard common in Europe for mounting positioners and accessories on rotary valve actuators.
VDE/VDI 3845
See Virtual Field Device
VFD