Some Issues with Auto-tune.

[Action22]

Hello,

V700 with V200-18-E3XB

I  am having some issue while trying to auto tune with PID SERVER. I let the autotune run with 2 cycles. by the time it complete i get a "run time error 6 overflow" error and PID server crashes. From what i understand it is a overflow error but I'm not sure how to fixt is within visilogic. Any advice appreciated. 

 

I am using a T/C to take temp of water then a PWM output to a solid state relay which would heats up water.

 

Attached is the project that is giving me the error

version 4.vlp

[Joe Tauser]

That's actually a program crash within the PID server.  It's been a long time since that module has been updated.  What happens if you Auto Tune the loop without it?

Joe T.

[Action22]

It seem like the auto tune never completes when just running from the HMI.  The process value will over shoot then drop underneath the set point multiple time (I have to atuotune set to complete after one cycle.) with out the autotune complete bit going high.

I was basing most of the ladder logic off this webinar

https://www.youtube.com/watch?v=EqEqEdOx-x8

 

[AlexUT]

1. Delete MI 8 power-up value -Sample Time.

It will be calculated by Autotune.

2. Water temperature range is 0 to 100.

It is recommended to set:

- MI 9 =0 (0.0)

- MI 10 = 1100 (110.0)

3. MI 0 show temperature in 0.1 C/F.

4. Change User Set point MI 47 format to 4.1

Entering 55.1 from display will be represented as 551 in MI.

4. Use MI 47 instead of MI 3.

5. Sample MI 0 in 4.1 format.

6. Delete nets 2 and 3.

Test it.

 

 

[Action22]

 thank you so much for taking the time to go through the program and giving us prompt feedback. Greatly appreciate it!! 

[Action22]

Auto tune is completing. Thanks for the advice!