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nasir_ash
Dear Team

pls help me, hoe to configure the pid instruction for a fastest pid response.

pls also send me the values of the the parameters from P1----P7

awating for your reply
NASIR
pfort
QUOTE(nasir_ash @ Apr 25 2009, 10:53 AM) [snapback]81519[/snapback]
Dear Team

pls help me, hoe to configure the pid instruction for a fastest pid response.

pls also send me the values of the the parameters from P1----P7

awating for your reply
NASIR


There are no "magic" values.
I suggest you start with PIDAT instruction if available in your PLC, then make autotune. That will give you good parameters to start to work with. Then you can modify them to make yourresponse fastest, etc.
In the Omron manuel it is well explained how the P, I, and D parameters affects the the speed and overshoot.
nasir_ash
DEAR TEAM

i need your help, for configuring the PID



the parameters i ma setting are as



P1=100

P1+1=9999

P1+2=9999

P1+3=4095

P1+4=225

P1+5=0001

P1+6=0808



BUT NOT GETTING ANY OUTPUT WITH RESPECT TO THE INPUT.



PLS ADVISE HOW TO ADJUST IT OR TUNE IT.



REGARDS

NASIR ASHFAQ

Sleepy Wombat
Firstly, program the flags associated with the instruction, ie P_Er, P_EQ, P_GT etc , these can give you a clue to where you have problems.
Secondly, the number you are using seem to be plcuked out of the air.
Thirdly, How are you entering the numbers ?

This could help you...

Assume an analogue input for the PV to be an analogue signal to be a temp input for example, and assume that the sensor will output 0-200 deg C to correspond to 4-20mA. this means that 20mA = 200 deg = 4000 on the analogue and 12mA == 100deg = 2000 and ocourse 4mA = 0deg = 0...

The analogues i will assume are 0-4000 so may as well define the pid output to be 0-4095 So C+6 make #0404 notice the "#"

so if we want a setpoint to be 100deg then C must be &2047... this means that you should scale the SV value before putting it in the PID

For P, C+1 you can start with say &500 (notice the "&"
For I, C+2 turn if off &9999
For D, C+3 turn if off &0000
For t, C+4 say &50 which corresponds to a 0.5 sec sampling period
Leave C5 alone, you clearly don;t know what you are doing...
C6 set up as #0404
Leave C+7, thru C+10 alone and make sure that you are not using them in your code either...


Read up about P&ID to understand how changing values affect the outcomes etc...
Search for P&ID on this web site.




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