Fiber Optic to PLC

[Wandering 0]

What adapter will/or should I need to connect a computer running Rsview to a ML1100 located one half mile away. Customer is requiring and supplying fiber Optic cable. That would be Computer to Fiber to plc. (Without requiring a computer at plc) • Rsview computer has a LAN card but not connected to Ethernet • Running Win XP • Running Logic 5 and 500 • Rslinx Gateway • Monitoring 3 Plc’s via dh+ • Micrologic 1100 requested for remote/new plc How about configuration for a SLC to? We have a separate application with above specs. but we can use wireless. Who is a reliable, tuff and not necessarily economical system??? Any help gladly appreciated

[Bill Linne 0]

Hi: At my plant we use Hirschmann products for all fiber applications. The stuff is very durable, and has provisions for dual 24vdc power supplies with auto switch-over in event a power supply fails. Hirschmann makes any number of configurations to suit your needs. The equipment is rail mount, small, and very reliable. Typical installation would be fiber cable from the main control system ethernet switch (which, in my case has fiber and copper ports) to the PLC cabinet, then a fiber x copper module to facilitate connection to the PLC. No special configuration necessary. You won't know the fiber is there once it is up and running. You can hire someone to terminate your fiber connections, or buy the equipment and with a bit of practice, learn to do the terminations yourself. Once we had all our PLC's on ethernet, I changed the MSG instruction rungs to use the ethernet path first, and in event that link results in a .ER bit, switch to the old DH+ MSG as a backup. Very robust system. Having fiber to the PLC cabinets adds great versatility (we used 6-strand fiber, and it takes two strands per circuit). So, I've got spare capacity to add security cameras on their own network segment if I want. You can review Hirschmann stuff here: http://hus.hirschmann.com/English/Industri...cts/index.phtml Regards, Bill

[Wandering 0]

WOW Seems to be good equipment, Thank you! I will contact a rep.

[manav 0]

Will the same specs run on ML1500 + NET-ENI? Will the serial to ENet conversion make any difference to the configuration or performance? I have this PLC config to be interfaced with PC at distance of 800 meters.

[TimWilborne 108]

No you won't get the same performance with the Micrologix 1500 and a 1761-NET-ENI as you would a Micrologix 1100 but all principles are the same when it comes to the fiber The 1500 still has a communications rate 38,400 so that will be your bottleneck. Interestingly in most applications the converter, such as the 1761-NET-ENI, is the bottleneck. But with the introduction of the Series D, one o the big features AB pushed was that they had optimized the communications between the ENI and the processor to the point that the throughput was actually greater than a direct serial connection

[Wandering 0]

Check out these links. I have been researching http://www.phoenixdigitalcorp.com/pdf_directory/Rockwell.pdf http://www.weedinstrument.com/product_groups/fiber.html hirchsmann There are more. Just WANDERING if anyone has used any of these? Or what type has been tested?

[Nathan 7]

Wandering - Lots of good advice here, did you get your question resolved? You don't need to worry about "fibre incompatibility" with industrial (ethernet) based devices. Basically you can treat on the PLC end like you're working over ethernet with the Fibre seamlessly connecting the distant ends. There are, of course, many different configuration/implementation options.

[manav 0]

But the ML1500 thru NET-ENI would still connect via fiber optic, at a distance of 800 meters even with reduced speed. Connection itself would not pose a problem? Since my RSView32 App is small it works fine over a serial port. Ethernet is the protocol to be used since RS-232 will not extend upto 800 meters. The network setup is in client's scope. All I have to do is give him go-ahead that thru NET-ENI I can connect the same app at 800 meters. Connection speed being reduced to that of a serial port is not a problem. But connecting the NET-ENI would not be a problem I suppose?

[BobLfoot 302]

Connecting the ENI should pose no problem. Client will need to provide an ethernet hub, switch or router for the ENI to connect to. I'd advise a service ethernet port {Pheonix makes some nice ones} at the remote location. That way you can connect an ethernet laptop to the eni and plc at the remote location and verify problem is network and not plc related. Just a thought.

[manav 0]

Thanks mate. The suggestion for a service ethernet port is very helpful, I will recommend the same to the client.

[paulengr 44]

Three ways: You can get a wireless serial modem. I like the ones from Aerocomm. Mouser (yeah, the electronics distributor) is one source. Don't bother with the NEMA 4 ones. It's just a fancy package. Get the regular ones. About $300 for a pair as I recall. This gives you 19.2kbps with a several mile range as long as it is the usual "line of sight". We run them all over a foundry. Much better than IEEE 802.11 modems because they will trivially penetrate steel structures and seem to do very well against RF noise makers (like 2800 degree molten iron...electron city). I have even used a KF2 box on the other end to go serial<-->DH+ so that the PC appears as yet another node on the DH+ network. Option #2: Put a fiber/Ethernet converter on each end. There are many sources for these. I'd just pull out a B&B Electronics catalog (www.bb-elec.com) and pick one. With control systems, not having a LAN isn't really a big deal anyways. "Domain controllers" and DHCP are just great ways to leave your control network locked up until the IT boys figure out what's wrong with their stuff this time. Just use static IP addressing and use the PC's default LAN configuration and everything will work fine. Option #3: Use option #2. Then install a KF2 box ($1500 :( ) onto your DH+ network to convert it to RS-232. Then install a Digi One IAP as a protocol bridge and a small switch ($1000...see B&B again). This lets you connect directly to the DH+ devices from the PC via the Ethernet connection as well as the Micrologix and allows for future expansion (one extra serial port, additional Ethernet ports, ability to utilize the DH+ network, and should you need it, access to open networks such as Modbus, Modbus/TCP, or Ethernet/IP). Watch out for what they install for fiber. If it is multimode (cheap), you are going to run into a bunch of trouble. Multimode fiber does NOT like distances over 800 feet. We've got a bunch of that garbage in my plant (1200 feet long, and the network terminates at one end). Better to start out with single mode fiber in my past experience for virtually all applications. The advantage of multimode is that it is cheaper, both in terms of price and quality. The advantage of single mode is that it can support effectively an arbitrary amount of bandwidth (via CDWM or DWDM if you ever need to exceed the OC-xx terabit speeds), that it's glass so it won't degrade over time, and that the transceivers are better built since anyone using it is paying for quality. The downside is that the transceivers are generally a little more expensive since we're talking telco grade here (single mode fiber has a range of about 20-40+ miles, give or take workmanship and transceiver limitations).

[Been Around 0]

Thank you so much. I have done alot of research lately and have learned a great deal. This really helps. We have to connect this to existing utility poles and cross a highway. I am going to have a hardwire cable for a backup if a limb falls and severes fiber optic cable. I will look for the best unit for a quick change from fiber to wires. I don't believe wireless will work as we have a substantial drop in elevation and lots of pine trees. I may try a unit anyway, there relatively inexpensive and worth the learning. Again , Thank you and happy programming!

[Wandering 0]

Thanks Paulengr, I will try the wireless