Mitsubishi FX3G-40M Fast counters

[Grimm 0]

Hello everyone,

So I have ran into a problem, finished programming and attached all of the elements, everything is new and clean (cables,wiring, etc).  But now when I am testing the x , y cords [X0,X1/X3,X4] ( I am using 2 phase  fast counters), the cords are being crippled after few rides, the cords differ from the set ones aka 0 point, and within time the difference increases. like when i am doing first ride around and move it back to set point everything is fine same thing for 2nd time. But after like 3 times, when its driven back to set point the cords have changed by 1 or 2 ticks, or by -1 or -2. Left the program running for 4 days and the difference was 28 at 0 point on X and 8 at 0 point on Y. And the counting speed is kinda slow so that shouldn't be the issue. Checked everything for possible interruptions, placed spacers between the encoder signal contacts and other signals so there would be no interruptions. Made a prog that checks all impulses so i can compare them for any changes, but numbers stay the same. One thing i thought about is that the difference might be done by a spin out, tho not sure about it. At the moment I am out of ideas about what could possibly cause this... And wanted to ask if FX3G-40M fast counters have some kind of allowed mistake? Or I have missed something.

PS. I am thinking about creating recalibration points, for example if it reaches X end switch, then cords what should be there are set. Is that a good idea? 

Thank you in advance,

Best wishes

Edited 26 Jun 2018 by Grimm

[Gambit 324]

Are you using Highspeed instruction (the ones that work outside of the SCAN)
DHSCS for instance 

 

 

[Grimm 0]

Yeah, I am using COUNTER32_M, with CC252 and  CC253 inputs,  and the CValue is set to 9999. And then using the CN252 and CN253 values.

Edited 26 Jun 2018 by Grimm

[Gambit 324]

Yes but how are you using these values in the program.

 

[Grimm 0]

Rough example:

Im using them directly like,

 

< If (CN252 = D255)   ;

than ;

Reset = Q10; 

Reset = Q11 ;

>

<If (CN252 < D255)) ;

than;

Set= Q10;

Reset= Q11;

>

<If (CN252 > D255));

than;

Reset= Q10;

Set= Q11;

>

< If (CN253 = D355)) ;

than ;

Reset = Q12; 

Reset = Q13 ;

>

< If (CN253 < D355)) ;

than ;

Set = Q12; 

Reset = Q13 ;

>

< If (CN253 > D355)) ;

than ;

Reset = Q12; 

Set = Q13 ;

>

Edited 26 Jun 2018 by Grimm

[Gambit 324]

Do you reset the Highspeed counters anywhere ?

 

 

[Grimm 0]

No im not doin it.