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Dave W.

Predefined Protocol Q/LCPU to Slow

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Hello, everyone
I have to query a SICK distance sensor from an L26CPU via the onboard Ethernet interface.

I have created a simple protocol which I start with the function block SP_ECPRTCL. Unfortunately it takes at least 25ms until the next telegram is started. The sensor responds within approx. 1.5ms. Does anyone know whether that works faster or is that a limitation when using the predefined protocols?

Sensor manual:  OD5000, 8021391 (sick.com)  (Chapter 7.4)

I am grateful for all the hints.
Thanks and regards
Dave

SICK_Protocol.tpc

Messaufbau_vTest.gxw

Edited by Dave W.

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Hi, the PLC has a cycle time of at least 25ms. With 25ms you are a happy chap! We have here on large Programs cycle times of up to 125ms and if we poll multiple devices we have reaction times of seconds!! We asked the country representation people. It is normal....

There is nothing fast with PLC and Mitsubishi. But probably all PLC's suffer from this. It is the Cycle time of the PLC.

If anyone knows a setup with Mitsubishi to read/write 6 Bits (!! yes bits !!!) to 30 external devices in under one second...I have open ears. 
And this in the age of 100Mb mobile connections.......Shannon and Moore are facepalming in their graves.

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Ahh...Country representation people = Dave W.:notworthy:

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On 17.9.2021 at 7:57 AM, DWIM said:

Hi, the PLC has a cycle time of at least 25ms. With 25ms you are a happy chap! We have here on large Programs cycle times of up to 125ms and if we poll multiple devices we have reaction times of seconds!! We asked the country representation people. It is normal....

There is nothing fast with PLC and Mitsubishi. But probably all PLC's suffer from this. It is the Cycle time of the PLC.

If anyone knows a setup with Mitsubishi to read/write 6 Bits (!! yes bits !!!) to 30 external devices in under one second...I have open ears. 
And this in the age of 100Mb mobile connections.......Shannon and Moore are facepalming in their graves.

Hi DWIM
Thanks for your answer.
My L-CPU doesn't have much to do. Cycle time approx. 2.5ms. It's more of a problem with the predefined protocol.

I made communication with many stations with FX5U and Ethernet / IP - Module. With 30 slaves from Moxa (ioLogik E1214) Unfortunately I can't remember the total transmission time.

Really fast communication is possible with iQ-R and CCLINK IE Field, but it is very expensive.

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On 17.9.2021 at 10:44 AM, DWIM said:

Ahh...Country representation people = Dave W.:notworthy:

Yes, I work for Omni Ray AG which is the representative of Mitsubishi Electric Factory Automation in Switzerland.
Unfortunately, I'm more likely to get help here than at the European headquarters. :-(

And you?

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