Simex multicon cmc-141, User Manual

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User Manual For - CONTROLLER/DATA RECORDER MultiCon CMC-99/141
Logical channel operating as PID controller generates "analog" output signal. This signal
can be limited to range suitable for used output. On the other hand all built-in outputs has
settings allowing to fit them to source signal (see
7.10.3. Build-in output - PWM (Pulse-
width modulation) mode for SSR relay output or 7.10.4. Built-in output - Current output ).
It is user's responsibility to choose correct limitation of PID output (as well as other PID
settings), but important is to set limitation range wide enough to obtain smooth controlling of
actuator, and narrow enough to make PID as fast as possible. We can assume that PID
output range is set as 0-100. To set this, user should enter
Controller
menu, select requested
controller and in
Controller output
parameters block set:
Offset : 0,
Low output limit : 0,
High output limit : 100,
Other PID controller settings depends only on application.
Lets assume that user has to use TC signal (K) for temperature measurement (module TC4
installed in slot A) and SSR output driver (module S8 installed in slot C) to control a heater
keeping set temperature of the object. Lets assume that temperature setpoint can be set
between 120 and 200
°
C.
To realise this task user needs at least 3 logical channels and 1 set of Controller settings.
Logical channel 1 – Measurement of temperature,
Logical channel 2 – Setpoint of temperature,
Logical channel 3 – PID controller,
Controller 1 – a settings of PID controller which runs in channel 3,
There are few basic, well known methods described in the literature to choose P, I and D
parametets optimal for the controlled process. If user is not familiar with these methods, also
some exemplary values can be used, suitable for demonstration of PID work process
controlling slow processes (like heating 1liter of water using 1000 Watt heater).
Mode : PID,
Dead zone : 0,
for Controller parameters block parameters:
P Coefficient
: 5,
I coefficient
: 10,
D coefficient : 1,
Differentiated signal : feedback (measured),
for Controller output block parameters:
Offset
: 0,
Low output limit
: 0,
High output limit
: 100,
for Initial conditions block parameters:
Init type : No init (internal state 0),
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