Yokogawa YVP20S - Manual (Page 115)

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<Toc> <Ind> <11. PID BLOCK SERVICES>
IM 21B04C50-01E
11.3 Simulation Function
The simulation state is allowed only for the users of privelege level 8.
ValveNavi provides a special function for testing and training. The user can connect the
valve position to the input of the PID with lag of 5 seconds to allow demonstration of closed
loop control.
WARNING
The simulation state must not be used if the valve is connected in a control loop or the if the
valve is controlling process flow.
The simulation state will permanently remove important control loop configuration
information from the YVP valve positioner. The soft-wired connection between the PID
functions block and its input function block must be restored after simulation is used.
Reconfigure function block links after using simulate.
11.3.1 Simulation State
This is a special state provided for training use only when the control valve is not operating
a process. In this state, the control valve position readback signal is fed back into the PID
input with a 5 second filter time. This will form a closed loop to simulate a process loop.
The PID block is in AUTO mode. (This is not the same as the Foundation fieldbus
SIMULATE parameter).
To enter this state the user must be logged onto ValveNavi with permission level 8. If there
is a configured link to a process input signal (PID.IN), SIM state will permanently remove
the link. For security, after using SIM state, the input signal link must be restored using
function block configuration tools.
To Use Simulation Function, the function block application (linkage between function
blocks) is necessary to be defined. By using Fieldbus Configureation Tool, define the
linkage between AO and PID blocks.
In PID Process Controller dialog box, clicking [SIM] button in the [Select] frame will show
the message to warn the entry to the Simulation mode. Confirm that the positioner and the
valve are isolated from the control loop and there will be no effect on the system, and then
click Yes. The connection of the closed loop mentioned as above will be done, and
Simulation mode will be started.
By changing the value of Process setpoint, you can see that the valve follows.
With using Trending function, the change in the process setpoint and the Valve target
position /actual position can be viewed in trend graph. (See Chapter 12)
After finishing the Simulation, check and re-define the function block application again, by
using Fieldbus Configuration Tool.