3200 Series
36 Part No HA028651 Issue 7.0 Apr-09
7.
Controller Block Diagram
The block diagram shows the simple building blocks which make up the controller. Each block has a list of parameters
headed by a list name. For example the ‘Input List’ contains parameters which define the input type.
The quick start code automatically sets the parameters to match the hardware.
The Temperature (or Process Value, PV) is measured by
the sensor and compared with a Setpoint (SP) set by the
user.
The purpose of the control block is to reduce the
difference between SP and PV (the error signal) to zero
by providing a compensating output to the plant via the
output driver blocks.
The timer and alarms blocks may be made to operate
on a number of parameters within the controller, and
digital communications provides an interface to data
collection and control.
The way in which each block performs is defined by its
internal parameters. Some of these parameters are
available to the user so that they can be adjusted to suit
the characteristics of the process which is to be
controlled.
These parameters are found in lists and the name of
each list corresponds with the name of the function
block shown in the above diagram.
The above block diagram applies to 3208, 32h8 and
3204 controllers.
For 3216 Output 3 and Logic Input B are not present.
Sensor
eg thermocouple
Output 4 (AA
Relay)
Eg Alarm
AA
List
(section 9)
To plant
actuator
devices
Sensor Input
Input List
(section 8)
Setpoint
SP
List
(section 10)
Control
CTRL
List
PID/on-
off/Tune/Auto-Man
(section 11)
Input/Output 1
Eg Heat
I O-1
List
(section 9)
Output 2
Eg Cool
OP-2
List
(section 9)
Alarm(s)
ALARM
List
(section 12)
Timer
TI MER
List
(section 13)
Digital
Communications
COMMS
List
(section 15)
RS232
Or
RS485
Digital Input A
LA
List
(section 9)
CT Alarm setting
CT
List
(section 9)
Current
Transformer
Input
CT
List
(section 9)
Inputs Control
Processes
Outputs
Output 3
Eg Cool
OP-3
List
(section 9)
Digital Input B
LB
List
(section 9)