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Examples of Applied Control Types Section 5-2
Function blocks used: ON/OFF Timer (Block Model 206)
Contact Distributor (Block Model 201)
(Step Ladder Program [Block Model 301] as neces-
sary)
The contact signals from the ON/OFF Timer block are connected to the MV
hold input of the Advanced PID block.
Note In processes where the dead time changes according to certain conditions,
make the hold time variable according to those conditions. (PI control of vari-
able sample cycle). In this case, set the ON time (T1) of the ON/OFF timer by
other function blocks.
Example
MV
T
1
T
0
T
1
T
0
Time
Advanced PID
Block Model 012
MV
PV
Contact Distributor
Block Model 201
MV hold
ON/OFF Timer
Block Model 206
Start of operation
ON/OFF operation
PID
MV
PV
Reaction
process