pturmel

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About pturmel

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  1. How often are you reading the values?  Some modbus devices time out connections for inactivity in as little as ten seconds.
  2. kenetix 5500 servo drive

    The two safety inputs for the safe-torque-off function must change state together, and not flicker, with a tolerance of one second.  Trace your safety wiring.
  3. kenetix 5500 servo drive

    From Rockwell's fault code spreadsheet:  
  4. RSLinx itself will do this, using the Ethernet/IP standard "List Identity" broadcast. Rockwell has more advance probing software.  (AssetCenter?)
  5. How to release/close CIP connections

    Multiple program terminals online?  Those count.
  6. Without networking at the machines, site visits is all you can do. With networking at the machines, VPN appliances are the cheapest and easiest, and require no further licensing. Many of the appliance options include cell modem options if a local network connection is impossible.
  7. A1S68AD CARD

    Are you sure that transmitter isn't also blown?  That value is suspiciously similar to what one would expect for 0mA.
  8. You will have to convert to bytes, with a four-byte length header.
  9. I switched from VirtualBox to KVM ~5 years ago.  Got tired of kernel conflicts.
  10. I use Linux's native KVM with VirtManager and VirtViewer.  No more crossing my fingers when updating the OS.
  11. Rockwell ControlLogix PLC setup

    I've bought various used AB items off ebay.  Be prepared for sticker shock if you try to buy recent stuff.
  12. Allen Bradley 5571 communication with DeltaV

    Is this the Mynah VIM card?  I ran across that once:  it emulates an I/O chassis to place in the Logix PLC's I/O tree.  Chances are, the I/O buffer in the Logix processor needs to have its assembly length changed.  Or possibly not needed, if the buffer has unallocated boolean space.  Can you share more details of your application?
  13. String clearing

    BTW, this can be simplified to just a single FLL targeting the .LEN element with a constant length of 22 42. {Edit: Whoops!  SLC, not Logix.}
  14. String clearing

    You have to ensure the empty source string stays empty.  Marking it as read-only or a constant is probably sufficient.
  15. Reading and Writing I/O tags in PLC

    At the first level in the Logix controller, a user may use an ANSI Symbol Segment containing a tag name in place of the symbol class and instance that the data access manual describes.  Using the class and instance is recommended for best performance.  When supplying additional path segments for array subscripts (Member segments) or named structure elements (additional ANSI Symbol segments), they are simply concatenated with the first level segment(s) to form a complete application path within the CIP request.  That CIP request must use the documented Logix tag read, write, or modify service codes and payload formats. The data access document I linked is a complicated slog, but I encourage you to read the whole thing if you are going to be doing tag access from a third party stack. Some additional information you may find useful: The Symbol class and Template class in the real Logix products I have in my lab do not implement "Get Attribute Single".  You must use "Get Attribute List" or "Get Instance Attribute List" as shown in that manual. There are undocumented attributes on both classes.  I encourage you to experiment.  I consider attribute #8 on the symbol class to be essential:  reading it yields an array of three UDINTs (as twelve bytes) that supply the array dimensions for the tag, with zeroes for unused subscript levels.  (All zeros if not an array.) Most devices that are intended to be used with implicit connections (I/O adapters) also support "Get Attribute Single" and/or "Set Attribute Single" for assembly buffers.  Attribute #3 of the desired assembly instance.  Reads or writes the entire data buffer.  (Writes to the output assembly will be rejected if an implicit connection owns it.)