AJ Melb

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About AJ Melb

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  1. Weather station

    I like THIS one
  2. FUS060 HART -> Modbus converter

    Hi all, I have a requirement to read Instantaneous Flow (easy) and Accumulated Flow (not so easy) from a Siemens FUS060 HART flowmeter. Instant flow can be read from PV or SV (depending on flowmeter config) - no problem there. The Moore Industries HCS device I'm using though, cannot request the Accumulated flow, which is in parameter 130, rather than a more accessible location. The gateway/converter needs to support: Send: 130,0 (Command 130, data length = 0) Response: 130,14 (data length in bytes), Totalizer forward (4 bytes), Totalizer reverse (4 bytes), Totalizer net (4 bytes). Has anyone come across a gateway that is a Modbus RTU slave (RS485 so I can multidrop a couple of them) and CAN retrieve this data? (it also must not insist on being the current source for the HART 4-20mA loop, as the flowmeter insists on being this) Regards AJ Something like THIS or THIS
  3. I'm testing/staging on a 5/05. The target hardware is a 5/04 with a Panelview already attached to Channel 0. The Motorola RTU is pretty nice - it natively supports Modbus, DF1, Modbus/IP so you'd think I could find a protocol/port in common :( I DO have a prosoft card - the MVI46-MCM. Its documentation is a bit scanty for SLAVE mode, but I'll persevere.
  4. I'm testing/staging on a 5/05. The target hardware is a 5/04 with a Panelview already attached to Channel 0. The Motorola RTU is pretty nice - it natively supports Modbus, DF1, Modbus/IP so you'd think I could find a protocol/port in common :( I DO have a prosoft card - the MVI46-MCM. Its documentation is a bit scanty for slave mode, but I'll persevere.
  5. Thanks for the responses. So this card is basically a KF2 sitting in a PLC rack to draw power /doh! It would have been nice if that was clearer from reading its manual. So its Prosoft or nothing when trying to add extra DF1 or Modbus ports ?
  6. I'll try that and report back. I'm guessing then that renumbering the DH485 to 2 or 3, and addressing 1 may also work. Seems a bit weird given there isn't anything connected to the DH485 port. But i've already tried much sillier things :)
  7. Hi folk, I'm trying to get a Motorola ACE 3640 to talk to an SLC5 processor, and have struck a snag. Configured as a DF1 master, the ACE talks fine to the channel 0 port of an SLC5/05, configured as per the 1st screenshot. However I really need it to talk to the DF1 port of a 1747-KE card, configured as per the 2nd screenshot. Soooo, my question is, what is the difference in configuration between these 2? as I'm scratching my head to find one. Half Duplex, CRC, 19.2k, n, 8, 1, slave addr1, ..... The symptoms I'm seeing is the DF1 light is flashing on the 1747, so its receiving messages. Its also transmitting responses as I can see the incoming data lighting up the receive led on the ACE - just no data sent or received to my sample N9 file, which works perfectly when I use the processor port. The 1747 doesn't require ladder to run does it? As you can see from the screenshots I set it up using a terminal session.
  8. Write throughput issue with ML1100/Rslinx/OPC

    More information in case anyone else has a similar problem: 1) There is definetly something fishy about N9:124 and above. Rslinx gives parameter errors when when this address (or higher is used), but N7:124 and above have no problem. I thought this could be related to using SLC-503+ as the controller, but it too from the documentation I've found can have N9 configured with up to N9:254, so that ain't it. 2) My write throughput problem is a loading issue - I can identically configure other PLCs and have no problems with writes, as long as I keep the number of points being read lower. I am NOT impressed with Rockwell's scanty documentation.
  9. How to intentionally make a program stop?

    It may be the reset only works if the timer condition is false/zero. If you the simpler TONs then having the logic feed them go zero/false will clear the timers. Additionally the accumulator or .ACC field is writeable in TON/TOF and I assume timers in many PLCs. Personally I dislike using latch and unlatch commands. It means drivers of the relay output are on separate lines, and its easy to do nasty things like oscillate contacts or leave latches in an indeterminant state. (Its the PLC equivalent of programming using if/then/goto = bad in my opinion) A cleaner/better technique is to have latching logic, where a contact holds itself in. Something like +---[ latch condition ]----------+----[ / Reset ]----------------( latch ) | | | | +-----[latch]---------------------+ If you will forgive the scrible. Latch holds itself in once triggered by the latch condition, until the Reset turns it off. So basically in your example I would have a whole lot of lines with a reset condition being your emergency door contact. "latch" can be a retentive contact or TON, if you need the state to survive run/program mode switches/power outages, or need delays. You can build up whole sequences and state machines this way (although I prefer numeric states for more complicated stuff) As for stopping a program - thats not a normal requirement either. You can stop execution of parts of a program by using subroutines, that you either call, or don't. Putting the entire PLC into program/stop is a one way trip if its even possible to do (forcing a fault like a maths overflow condition would do it in some PLCs but that ain't nice). When not limited by resources such as scan time, the normal/logical way to program is to have all the main logic run each scan, and just not do anything if not required. ie write your logic such that you expect it to be run all the time, with enough contact conditions on key lines that nothing happens when its not supposed to. Hope this doesn't confuse you further. Regards AJ
  10. Write throughput issue with ML1100/Rslinx/OPC

    Thanks for the link. Thats an interesting article, and one that appears useful for a niggling background problem I had - the RSLogix loader dropping out periodically, especially when doing online edits It doesn't unfortunately resolve the write errors I'm seeing though. I have gleaned a bit more information from Rockwell Knowledgebase & Tech support - SLC-503+ is the correct device to configure, and of the 2 interfaces that work (Ethernet Devices & Ethernet/IP driver) the Ethernet/IP Driver is the newer/preferred one to use. Still playing around with communications parameters and annoying Rockwell tech support - will see how I go.
  11. Hello forumers, I was wondering if anyone has had peformance issues in writing data to ML1100 PLCs? The system we have is 3 (eventually 20) Micrologix 1100 PLCs connected to a SCADA system via rslinx 2.5 and OPC over ethernet. After a bit of bumbling around to configure the OPC (ML1100 documentation is a bit scanty) I have it working fine for reads using: Ethernet/IP Driver (should this be Ethernet Devices?) SLC-503+ plc (as there is no entry for ML1100) Polled Messages at 1000ms (default) Communications Time-Out 5s Maxium Packet Size (ethernet) Update Hotlink after a poke I've fiddled wth the ML1100 channel 1 "Message Servicing Selection / Comms Servicing Selection" - both normally left ticked. For clarity all the SCADA data is stored in a single int file (N9) and varies from 40-100 registers per PLC. These are polled at 5sec intervals and Active DDE/OPC topics and Communication Events show the topics - 1 per PLC healthy. The PLCs do talk amongst themselves - a couple of MSG polls peer-to-peer each with a 1sec delay timer on each .DN or .ER A problem arises when I attempt to write a few registers in quick succession to a PLC, either manually from SCADA points or programatically. The SCADA system (Honeywell's Experion) gets timeouts, but I can't see anything showing up in Active DDE/OPC topics or Communication Events. I'm guessing there is some throughput related parameter I haven't configured appropriately, as the server itself is idling (3% processor usage on task manager), and none of the PLCs have scan times >40ms (they are fairly packed). Timeouts like this were more an issue back in the days of 1200baud serial links, not full duplex 100MB ethernet. Any hints? As soon as I start fiddling with settings I find the interface stops working entirely (generally with terse parameter errors in Active DDE/OPC topics), and restoring rslinx from a backup seems to be the only way to fix things (resetting original values and rebooting the server does nothing), which slows testing a fair bit. Regards AJ