Incremental encoder issue when shutting down the plc

[khiraly 0]

Hi! I read the incremental encoder using the PRV function and save it directly to the D (non-volatile) memory: PRV #10 #0 D202 The problem is, when I shut down the plc (CJ1m CPU22), sometimes it saves wrong data in the D area. And also there are some random data in the D memory, in areas which I do not touch. So the question is: When I shut down the plc (disconnect from the mains using contactor) the internal voltage does not stop immediatly and maybe there is not enough voltage to write successfully in the memory? This could be the case? If yes, how can I protect the PRV function from the low internal voltage? (currently the PRV function is directly connected to an always ON) And a completely unrelated question: I need to monitor 6 incremental encoders. The CJ1M cpu22 has 2 internal high speed counter. Is it an expansion modul which provide high speed counter? Or how can I read 6 independant incremental encoder in the same time? (from the same cpu) Oh, there is somewhere a summary sheet for reserved memory areas? So which D an CIO areas are reserved for internal usage? I usually use this areas: CIO 30.00 - 40.00 CIO 100.00 - 120.00 CIO 300.00 - 350.00 CIO 30000.00 - D 100.00 - 120.00 D 200.00 - 400.00 D 30000.00 -

[ECSI 17]

This is all spelled out in the Memory Areas section of the CJ Operation Manual

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"Oh, there is somewhere a summary sheet for reserved memory areas? So which D an CIO areas are reserved for internal usage?" Omron Knowledge Center http://www.omron247.com/doc/pdfcatal.nsf Use the Search argument "W393" then download pdf. Memory layout is covered in SECTION 9 of W393.

[khiraly 0]

With CJ1M I dot think there is a memory address. So if you take a look at the screenshot, the PRV command is like this: PRV #10 #0 D202 So the "port specifier" is #10 constant. How can I determine what is the real address of this high speed counter? Is there somewhere in the CIO area. I use the following commands for counter manipulation: Restoring the last value when the plc is switched on: Read the actual value: Make a reference (limit switch): When I restore the last value when the plc is switching on, should I use the first cycle flag? Bits N Bytes: Omron Knowledge Center http://www.omron247.com/doc/pdfcatal.nsf The search function does not work for me (timeout: error the requested url could not be retrieved).

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Looks like you also need the CJ1m Manual!!! Select Programmable Logic Controllers (PLCs) And search for W395. Physical address for high speed counter 0 is CIO 2960.08. You may also find this article helpful:- http://forums.mrplc.com/index.php?autocom=downloads&showfile=268 Attached is extracted page from this manual. CJ1M_IO.pdf