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4-95
Chapter 4. Functions
For model numbers where the 6th and 7th digits are 11, 21, or 22, internal cascade can be selected in the loop type
settings.
In the internal processing of the controller, the master-side MV can be converted to slave-side RSP. No output of the
master-side MV to a device outside the controller by analog output is necessary, and no input of the slave-side RSP
from a device outside the controller by analog input is necessary.
z
Master/Slave
The control on the master side operates as loop 1 control. PV1 becomes PV on the
master side.
The control on the slave side operates as loop 2 control. PV2 becomes PV on the
slave side.
The MV on the master side is converted into the RSP on the slave side through
scaling calculation.
This device
Master-side control
(LOOP1)
Scaling calculation
Slave-side control (LOOP2)
SP set value
PID set value
SP set value (LSP)
PID setting value
PV on master side
MV on master side
RSP on slave side
MV on slave side
Control target on master side
Control target on slave side
PV on slave side
PV1
PV2
Output
Handling Precautions
•
PV of block A4 (analog input) becomes PV on the master side.
•
PV of block B4 (analog input) becomes PV on the slave side.
•
RSP of block A3 and block B3 (analog input) cannot be used in the internal
cascade.
z
Loop Types
To use internal cascade for control, set the loop type to "9: Internal cascade," "10:
Internal c 1 loop," or "11: Internal c 2 loops."
Handling Precautions
•
The selectable loop type differs depending on the model number.
4-1, "Loop Types,"
Model numbers and loop types (p. 4-1)
The loop type can be set by the SLP-C7 Smart Loader Package.
4-1, "Loop Types,"
Setting the loop type (p. 4-4)
.
4 - 17 Internal Cascade