UM353-1
4.9 FCO122 - Cascade Control w/ Operator Setpoint Limits
Factory Configured Option FCO122 provides two loops configured for Cascade control. The block diagram of the
configuration of the two loops is shown below along with the changes made to the default parameter values of the
configured blocks. The process range of the Primary loop can be changed in Analog Input 1 and the range of the
Secondary loop in Analog Input 2. Also, the output range of the primary PID controller must be changed to match
any new range in the secondary loop. If the loop tag 'PRIM' or 'SEC' is changed, all configured references will
automatically be changed to the new tag.
TV
SETPT
TC
SR
LU
LD
Primary Process
O1
AIN1
QS
P
D
ALARM
TV
SETPT
TC
SR
LU
LD
Secondary Process
O1
AIN2
QS
P
D
ALARM
(Rev. 2)
Primary Loop
SETPT - Setpoint Function Block
RG PTR - Range Pointer -------- PRIM.AIN1.OR
INPUT TV - Input TV ----------- PRIM.AIN1.O1
INPUT TC - Input TC ----------- PRIM.A/M.NA
INPUT LU - Input LU ----------- PRIM.SPLIM.HS
INPUT LD - Input LD ----------- PRIM.SPLIM.LS
ESN - Exec. Seq. No.------------- 5
March 2003
O1
S
SPLIM
O1
A
HS
LS
P
S
F
P
A
I
A1
A2
A3
A4
NC
NO
PB2SW
PS
MD
ST
E
O1
I
IO
P
S
F
P
A
I
A1
A2
A3
A4
SPLIM- Setpoint Limit Function Block
RG PTR - Range Pointer --------- PRIM.AIN1.OR
INPUT A - Input A --------------- PRIM.SETPT.O1
ESN - Exec. Seq. No.------------- 10
Factory Configured Options
O1
A
O1
PID
AE
TV
AS
A/M
AW
TC
NA
EM
MS
ES
SS
O1
SPLIM
O1
A
HS
SE
LS
E/I
SI
IS
ES
O1
A
O1
PID
AE
TV
AS
A/M
AW
TC
NA
EM
MS
ES
SS
V
PRIM (Primary)
A
B
OR01
O1
C
A
B
OR02
O1
C
S
S
AOUT1
D
QS
Valve
V
SEC (Secondary)
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