larryllix Posted August 5, 2016 Posted August 5, 2016 Is there a certain way to list the address of a Modbus port in NodeLink? I have tried 192.168.0.64 but the other end refuses to connect. I have tried 192.168.0.64:502 but NodeLink reports "unable to resolve". Would port 502 not also be https ?
io_guy Posted August 5, 2016 Posted August 5, 2016 Modbus has nothing to do with https, completely separate protocol. It's standardized port is 502 and is currently not configurable. The 192.168.0.64 is correct, no idea why it refuses.
larryllix Posted August 5, 2016 Author Posted August 5, 2016 Modbus has nothing to do with https, completely separate protocol. It's standardized port is 502 and is currently not configurable. The 192.168.0.64 is correct, no idea why it refuses. All I get for info is that it is Sunspec protocol on a OutBack Mate3 interface/bridge box. It wouldn't surprise me as OB has massive problems with comms and has spent years floundering. This is another new thing for them. Maybe a few years after they get their main product working they may get to it. More digging later that afternoon later. Thanks Rick
Michel Kohanim Posted August 5, 2016 Posted August 5, 2016 Hi larryllix, We already have a Polyglot working with Outback inverters. You may want to send a PLM to einstein.42. With kind regards, Michel
larryllix Posted August 6, 2016 Author Posted August 6, 2016 This appears the NodeLink / Modbus interface is for maybe a slave emulation and not a master since there is no mapping provisions and other required setup clues. I need analogues to stuff into ISY but it won't talk to my OB Mate3 and I don't see any mapping or provisions to map those? Thanks.
io_guy Posted August 6, 2016 Posted August 6, 2016 Nope, it's master. Currently limited to discrete IO with default register mapping (because that's all I have and need). Was waiting for new users to add anything else required.
larryllix Posted August 6, 2016 Author Posted August 6, 2016 Nope, it's master. Currently limited to discrete IO with default register mapping (because that's all I have and need). Was waiting for new users to add anything else required. OK Thanks. This slave seems to have 1000s of registers so custom addresses are needed to pick and choose registers, filtering out the massive amount of junk. It's been a long time since I have set up anything Modbus so I am not sure how the analogue values work or if there is even a difference than coils and contacts. That seems to be a PLC style terminology, I never used. I spent a few years, after that, working with DNP 3.0 so feel quite confused by Modbus now, even with it's brutal simplicity.
larryllix Posted August 6, 2016 Author Posted August 6, 2016 Can you even connect (initial post problem)? No. I forgot about that. I d/l and ran Modbus Poll, found and viewed some of the registers to prove the OB Modbus port even works. It does work. OB keeps tooting this is a SunSpec Modbus protocol, supposed to be some standard protocol.
io_guy Posted August 6, 2016 Posted August 6, 2016 Sunspec is just a standard register addressing scene. Should still be Modbus. If you can open it up for me to connext remotely I may be able to work on it. Otherwise we're likely biting off more than we can chew.
larryllix Posted August 6, 2016 Author Posted August 6, 2016 With DNP 3.0, the protocol was so big that implementation standards had to be developed to make devices compatible with each other, despite all being DNP3 so I assume the same implementation thing has developed for Modbus. I don't imagine the basic protocol should have changed.
io_guy Posted August 6, 2016 Posted August 6, 2016 I have no idea where you're going with this. DNP has nothing to do with Modbus.
larryllix Posted August 6, 2016 Author Posted August 6, 2016 I was just trying to explain what SunSpec is.
io_guy Posted August 6, 2016 Posted August 6, 2016 If it's DNP then NodeLink won't work, but it appears to support both.
larryllix Posted August 6, 2016 Author Posted August 6, 2016 It's not DNP3.0. It's Modbus and it responds to Modbus queries. DNP3 is a massiive protocol language supporting audio, video, and custom packages inside. Electrical utilities love it for equipment comms but Modbus just doesn't support them well enough. . Modbus is a very basic fixed length protocol with simple formats and standards. SunSpec is a standardisation of Modbus, on a much simpler scale, to make things work together, by standardising the addresses of registers making mapping more..."expected" Just cleaning up, I just threw my 1300 page DNP3 guide in the junk last week. The nightmares are starting to cease. LOL This is all having fun and you are right, the initial problem is: OB equipment will not answer NodeLink's poll, for some reason. I am not sure if there is some special security stuff that has to be first. The protocol can shut my equipment down so security has to be there. I am not sure what "refused connection" means. SunSpec does not specify any of the higher level protocol stuff like passwords or user name etc.. AFAIK.
io_guy Posted August 6, 2016 Posted August 6, 2016 Let's get back to my previous post... If you want to point me to the protocol and open your port to the internet, I can try to help. I have no chance of guessing why the connection was refused. Modbus is not encrypted so you could also Wireshark the Modbus poll chatter and see what's being negotiated.
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