Ken Roach

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About Ken Roach

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  1. In general, Node-Red needs to run on a Linux computer of some sort, and of course the Arudinos are an interpreter running on a microcontroller. Modbus/TCP and Modbus/RTU are both part of the ordinary Arduino Modbus library.    https://www.arduino.cc/en/ArduinoModbus/ArduinoModbus So OP should start there, and ask specific questions in an Arduino forum.   Just this week I discovered two really cool ways to splice an Arduino to a higher-level control system.    One is an Uno R3 board with an expansion that lets you mount a FriendlyElect NanoPi Neo Core, running Debian.    Another is that Hilscher makes an industrial ethernet Hat for Arduino, pre-configured as an EtherNet/IP Adapter that talks to the Arduino over I2C.
  2. To clarify:  the PV+ has a "Global Connections" feature that includes the ability to have the terminal read tags from the connected controller, then apply them as time/date settings to the Windows CE operating system on the terminal.    Check the "Global Connections" section in the FactoryTalk View ME project. It's not impossible for the terminal's own RTC backup battery to be dead.   I don't recall how easy they are to get to on the PV+600 terminals.   I think the default time is the beginning of the Unix epoch (1 January 1972). PanelView Plus has had more than its share of bugs with the system clock.   RA's reluctance to simply let the dang things update from an generic NTP server remains a mystery to me.
  3. RSLogix 5000 and devicenet

    I realize you've probably already done this, but wanted to chime in. All A-B DeviceNet scanners store their configuration in nonvolatile RAM separate from the PLC program.   It's loaded into the scanner itself, and can survive power-down indefinitely. I would be a little more cautious with a "redundant FlexLogix" system.    Any hot-standby or DeviceNet "redundancy" system will not be as easily integrated and reliable as true ControlLogix redundancy. As long as the 1788-DNBO module (and the 1788-ENBT, for that matter) have retained their configurations despite the controller fault, they can be re-used without any reconfiguration.
  4. Connecting Micro800 to SCADA via SMS

    There was a GSM modem module available for the Micro 800 series controllers, marketed and supported by ProSoft Technologies in California.   But I think its heyday of the ILX-800 was eight years ago, before the advent of many other wireless gateways and IOT protocols. What sort of GSM networks are available where these controllers are installed ?   What sort of SCADA software are you using ?    There may be other network gateways, especially ones the use protocols like MQTT, that are more appropriate than trying to use Short Message Service. And of course the task of "connecting multiple controllers to one another" is a little different than "connecting multiple controllers to a central control and supervisory system".  
  5. Numatics DeviceNet I/O

    Modular I/O systems can certainly be tricky on any network, especially one that treats them like a blob on differently sized data the way DeviceNet does.   I have a lot of DeviceNet experience but not with the Numatics G3. What other devices are connected to the G3 adapter, other than that Input module ? What was the context of the failure;  why did you replace both the communications adapter and an input module ? How do you read the Input data connection size, and set it;  through the EDS-based parameter editor in RSNetworx, or through some other tool or utility (or the onboard display on the Numatics adapter ?).
  6. DF1 Protocol For Bit Read

    I'm not a protocol driver author, but in general I'd initialize to zero when you open a connection or restart the driver, then roll over at 65535.
  7. DF1 Protocol For Bit Read

    Thanks for the followup ! Most A-B devices can be set for BCC or CRC, but SLC/MicroLogix default to CRC.   As you've found, it's a fairly ordinary CRC-16 checksum, so it's 2 bytes instead of 1. Remember also that the Transaction Sequence Number should increase by one every time you send a command;  the reply for that specific command event should have a matching TSN. The sequence numbers are one of the things that distinguishes DF1 from Modbus and allows true full duplex communication. Some A-B devices can be configured to ignore duplicate packets, so sequences of the same command with the same TSN will ignore all but the first one.
  8. how to change Panelview300 from DF1 to DH485

    There is a link in the thread above that tells you exactly how to load the DH485 or DF1 firmware into one of those terminals. If your question is really "I don't have the firmware, will someone please provide it for me", then ask THAT question.  
  9. Powerflex 755 Net I/O Timeout

    "Auto-Negotiate" is not the same as "Auto-Detect". A port that's set for auto-negotiation, depending on the exact implementation in the low-level firmware, will periodically drop the link and try to re-negotiate a link speed and duplex, even if it's already running at the highest link speed and full-duplex supported by the device.     With most ordinary IT gear, that's not a problem.   Your e-mail and web browsing and even YouTube won't notice a 100 ms drop in the link. But a cyclic I/O connection generally will. Let us know your outcomes, if you get an opportunity.  
  10. Powerflex 755 Net I/O Timeout

    Why ?   Unless you have also set the switch to 100/full and disabled auto-negotiate, you might be getting link drops in order to attempt auto-negotiation periodically. I do not recommend disabling auto-negotiation unless you have hardware (like some fiber/copper converters) that requires it. Your Class A subnet suggests these drives are on an enterprise network.   Are they isolated, or seeing a lot of other broadcast / multicast traffic ? Have you set up a port on the 708TX to mirror the CompactLogix traffic to ?   That will be where you connect and use Wireshark.   Generally the 708TX is a battle tank of a switch, well suited to ordinary automation projects. With the faults being so frequent, you should be able to get some diagnostics just from the link status LEDs on the switch ports to which the PowerFlex are connected. Are there any other I/O adapters or devices that also show faults/disconnections in the I/O tree of the controller ?  You may need to monitor those with GSV instructions or just watch the status indicators in the I/O tree while online.  
  11. Redundancy Processor Online Modifications

    If this is true "ControlLogix Redundancy", then you don't have to do anything to the Secondary because it automatically transfers all the edits from the Primary. This includes changes to the ControlNet configuration, if you're using ControlNet. I recently revisited a Redundant system running v19.52 and the hardest part was disabling redundancy so I could save to the CF card on both controllers.    And convincing the customer that there was no such thing as "running on secondary";    they simply couldn't comprehend that Chassis A and B were not "primary and secondary".   Bit of a language gap.  
  12. 1756 ControlLogix connect with 1734-ib8s

    You cannot use POINT Guard modules as though they were ordinary I/O modules, or with a non-GuardLogix CPU.  
  13. Devicenet to RS232 re-formatting

    Disclosure:  This is the sort of thing I do for a living, but obviously it's a pretty expensive thing to contract out.   I'm happy to discuss it directly.
  14. Devicenet to RS232 re-formatting

    Followup:   I got out my Hilscher SyCon.net configuration software and created a new project for a NetTap NT100-DN-RS, which is a DeviceNet Slave on one side and a programmable serial device on the other. The Configuration screen does let you change the default ID object Vendor, Type, Code, and Revision from representing a Hilscher NT100 gateway to anything you wish.  So that would let you get around the electronic keying issue.    You can set the I/O connection size to anything you like, so you could emulate the data size of the existing pressure controller. I have never used Hilscher's NetSCRIPT engine to program a serial interface.   That might or might not be a way for you to use the NT100 as a gateway for this application.  
  15. Devicenet to RS232 re-formatting

    Unfortunately, without access to the DeviceNet master configuration, what you want to do is either impossible or very difficult. While that MKS device is very useful (and a classic;  I wrote some of the first A-B technotes using it in 1999) it has a slave data layout that's built for ASCII string transfers and almost certainly doesn't match the pressure controller's data layout.     Imagine you're exchanging eight 16-bit words of data.   The "group 2 only slave" standard just means that the data gets from Point A to Point B every X milliseconds.   It doesn't say anything about what each word means or does. There's also the issue of electronic keying;  most master devices check the Identity Object and won't connect to a device that doesn't match what they expect.  If I was going to take this on, I would need a DeviceNet slave whose ID object could be modified, and which is custom programmable on the serial slave side.   The Hilscher NT100-DN-RS might do the job, or a Red Lion DSPSX with a DeviceNet slave.    I have used both of those devices but never tried to change their Identity Object. To analyze the network, you would need either a raw CANBus analyzer (and a very strong DeviceNet background) or a more sophisticated tool like Frontline Test Equipment's NetDecoder. Compared to paying the OEM to modify their program to work with a different pressure controller, how much effort and time can you put into this ?