YOKOGAWA F3CU04-0S User Manual

C1-1
IM 34M06H62-02E 2nd Edition : June 2008-00
C1. Controller Mode
The controller mode defines the interdependency of the four controller loops of the
module. When the controller mode is set to single loop, each controller operates
independently. When the controller mode is set to cascade control or two-input
changeover control, a pair of controller loops 1 and 2, or a pair of controller loops 3
and 4, cooperate to function like a single controller. For an overview on control
modes, see Section B3.1.3, "Controller Mode."
The controller mode selection uses the MD12 or MD34 register for a pair of
controller loops 1 and 2 or a pair of controller loops 3 and 4 respectively.
Table C1.1 Parameters Related to Controller Mode
Data Position Number
Symbol Description Unit Data Range
Default
Value
Attribute
Stored
Loop1 Loop2 Loop3 Loop4
83 MD12
Controller mode
None
0: Two single loops
1: Two-input changeover control
2: Cascade control
3: One single loop
(odd-numbered loops are disabled)
4: Both loops are disabled
0 RW 
84 MD34 None
Table C1.2 How Controller Loops are Used according to the Controller Mode Setting
Symbol Description
How Loops are Used
Odd-numbered Loop
(1 or 3)
Even-numbered Loop
(2 or 4)
MD12
MD34
Controller Mode
0: Two single loops Single loop Single loop
1: Two-input changeover control Cooling input
*
1
Heating input
2: Cascade control Primary loop of cascade Secondary loop of cascade
3: One single loop
(odd-numbered loops are disabled)
Disabled Single loop
4: Both loops are disabled. Disabled Disabled
*1 Only the input side of the loop is used.
For details on Single Loop, Cascade Control, and Two-input Changeover control
modes, see Sections C1.1, "Single Loop," C1.2, "Cascade Control," and C1.3,
"Two-input Changeover Control" respectively. For details on how to disable the
controller functions, see Section C1.4, "Disabled Mode."
The MD12 and MD34 (Controller Mode) registers are controller parameters. Changing a
controller parameter normally reverts all parameters of the module to their default values.
However, switching between the values 0, 3 and 4 (between the disabled-mode and
single-loop settings) of MD12 or MD34 does not initialize the parameters.
The Controller Mode settings must be enabled to take effect. For details on how to
enable settings, see Section B2.3, "How to Enable Settings."

YOKOGAWA F3CU04-0S Specifications

General

Brand	YOKOGAWA
Model	F3CU04-0S
Category	Control Unit
Language	English