Classic GOOSE is fast because it’s simple. An IED drops an Ethernet frame on the LAN, every subscriber on the same Layer 2 network picks it up, and nothing in between has to think. Sampled values work the same way. That simplicity has a hard limit: the first router. GOOSE and SV have no IP header. A router… Read More: R-GOOSE and R-SV: Routable GOOSE and Sampled Values »
Network variables get all the attention in LonWorks. They’re the clean part: bind an output to an input and values flow. But a lot of the traffic on a real channel isn’t network variables. It’s the commissioning tool installing nodes, a gateway tunnelling another protocol, a SCADA master reading status, and nodes answering all of it. That traffic… Read More: LonTalk Explicit Messages and Network Management, Byte by Byte »
Almost every LonWorks page online is about air handlers and lighting. That’s half the story. LON was also a station bus in MV and HV substations. ABB built a whole protection and control range on it: REF 54x feeder terminals, REC and REM units, SPACOM relays behind gateways, and MicroSCADA on top. Those systems are still in service.… Read More: LonWorks in Substations: LON Bus for Protection and Control »
Putting LonWorks on an IP network sounds like the easy part. The protocol doesn’t change, and Ethernet is already in the building. Then a device stops forwarding and nothing in the LonWorks tooling explains why. ISO/IEC 14908-4 doesn’t rewrite LonTalk into a different application protocol. It transports LonTalk packets over IP using a mechanism it calls CNP/IP. But… Read More: LonTalk over IP (IP-852): Setup and Troubleshooting »
Most comparisons of these two treat them as rivals picking a fight over the same job. That framing gets the engineering wrong, and it gets one important fact wrong too. BACnet defines LonTalk as one of its own data link layers. Clause 11 of the BACnet standard specifies how BACnet messages ride on the LonTalk protocol. They are… Read More: LonWorks vs BACnet: How the Two Data Models Differ »
The power line channel is the one that fails for reasons nobody wrote down. A surge arrester goes in on the same board. A lighting retrofit lands on the same circuit. Both are perfectly good electrical work, and both can take the network down. ISO/IEC 14908-3 is unusually direct about this. It declines to specify the medium at… Read More: LonWorks Power Line: The 125-140 kHz Channel Explained »
Free topology is the reason people put up with LonWorks wiring. Bus, star, loop, or any mix of them, on one pair, with one termination you can put anywhere. No daisy-chain discipline, no polarity to get right. It isn’t free of rules. It has distance limits, a termination that has to be the right value, and a power… Read More: LonWorks Twisted Pair Wiring: Distances and Link Power »
A Modbus register is sixteen bits and nothing else. What those bits mean lives in a document somebody emailed you. A LonWorks network variable carries its own type. Two devices that agree on the type exchange a temperature without anyone deciding whether it’s tenths of a degree. That difference is the reason the protocol exists, and it’s also… Read More: LonWorks Network Variables: Selectors, Bindings and Polls »
Pick the wrong service type and the network still works — until it doesn’t. Under light load everything delivers. Under load, the acknowledged multicast you specified starts eating the channel it needs, and the symptom looks like a hardware fault. ISO/IEC 14908-1 gives you four services. This is what each one actually does on the wire, when to… Read More: LonTalk Service Types: Which One to Use and Why »
Every LonTalk packet carries both a source and a destination address, and both live in the same header. There is no separate layer-2 addressing underneath — the standard folds routing and naming into one address field. Get the structure of that field straight and most of the network’s limits, quirks, and failure modes stop being mysterious. This is… Read More: LonTalk Addressing: Domain, Subnet, Node, Group and Neuron ID »