Intergas Eco RF vs HRE

The protocol is manipulating current in one direction and voltage in the other so wired.
It is no such thing. Find out what a digital communications protocol is. Or for a short simple taster re-read what I have wrote.

From the OpenTherm web site:
Standards for heating controllers
OpenTherm is a multi point to point communication protocol for use in residential heating. Furthermore, OpenTherm requires a standard type of connection like in any modern installation practice, i.e. a 2-wire low voltage and polarity-free connection. In addition OpenTherm can also be used as a wireless protocol.​

I doubt if any of you will understand most of this. It even gives the bits breakdown of the protocol.
https://www.domoticaforum.eu/uploaded/Ard M/Opentherm Protocol v2-2.pdf

OT/+ The OpenTherm/plus protocol provides a digital communications system for data-exchange between two microprocessor-based devices.​

3. Physical Layer describes the characteristics of the physical medium and the method for bit-level signalling.
4. OT/+ DataLink Layer describes the composition of OpenTherm/plus frames and allowable conversation formats.
5. OT/+ Application Layer defines data objects and the mechanisms for transfer of application data between the boiler and room controllers.​

It was based on OSI (Open System Intercommunication), which is an open protocol suite, which was being pushed heavily by governments as it was non-proprietary, for general computer to computer communication. If all conformed to OSI all equipment made by anyone in the world could talk to each other. It never took off, but parts of its layers are in many other protocols. OpenTherm has an applications layer, datalink layer, etc. The layers are software, written and burned into firmware. Every OpenTherm device must have a microprocessor to communicate.

I don't expect anyone on here to understand the deep level aspects of the protocol, as you have no need to know it. A protocol is a frame split into selections with each section containing information. Look at this:
https://en.wikipedia.org/wiki/Ethernet_frame#Preamble_and_start_frame_delimiter
The above shows an Ethernet frame. OpenTherm will have something like it.

OpenTherm is a microprocessor (computer) protocol specifically for heating/cooling systems. The sections of the OpenTherm frames may relate to temperature, which is master, which is slave, etc. Each device acknowledges receipt of a frame to the sender, so constant two-way communication.

The layers of the protocol (each layer has a specific function) translates raw bits into information and even giving a man-machine interface that is represented in symbols (numbers and words), for humans to easily understand. Insisting that computers represent the man-machine interface as symbols, not O or 1s, was Alan Turings greatest achievement. Hence the screen you are looking at right now to communicate with the computer you are currently operating.
 
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As VC said - the RF will be proprietary. The final link to the boiler will be OT via the base station.
The RF signal may be proprietary, so sender and receiver have to be on the same RF signal. However the protocol frames in the series of transmitted bits will be the OpenTherm standard.

As with the T6R, the OpenTherm protocol is sent from one device to another using a mixture of RF and copper wires. As long as the boiler is standard OpenTherm it can understand the sending device, which has to get the protocol onto copper wires for the boiler's microprocessor to understand. Before it gets OpenTherm onto copper wires it can do what the hell it likes to get it there by running it over any RF signal type it likes.

The T6 is a hard wired device which will use the OpenTherm protocol at the device then sending down the wires to the boiler's microprocessor. The T6R will do the same except throw the protocol over its own RF signal, then transfer it onto copper wires by the RF base station.

You are right in that one makers RF signal may not be compatible to anothers, but they are still throwing the standard OpenTherm protocol over the RF signal, whatever it is.

No one here has got anything right about it.
 
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It is possible to send an OpenTherm frame as the data inside an Ethernet frame. That means you can send OpenTherm over a Local Area Network (LAN) - a LAN is the cable from your computer to the modem, a LAN can have 1,000s of computers on it, you have just one or two. At the final destination the Ethernet frame is stripped down as it goes up the software layers until there is only the OpenTherm protocol left. Then OpenTherm is handed to the OpenTherm device or monitoring system (installers app on laptop, users app on a Smart phone for e.g.). This this stripped down to get the data inside the OpenTherm frame.

So, you can send OpenTherm protocols around the world.
 
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Triggered much :LOL: Google must be in melt down..


You still haven't found an RF OpenTherm stat have you. The comms between the components is not OpenTherm it's Ramses (in relation to Honeywell). You can cut and paste volume after volume of stuff on OpenTherm that does not make it a fact that its used in the way you are insisting.

BTW, v3 of the spec makes interesting reading too, but then I doubt you have that ;) :p.

Do you have an OpenTherm monitor? Do you have an HGI80? No? I do. I've been packet sniffing my boiler and OpenTherm based wireless multi zone Heating controlleslrs for years.

The fact OpenTherm works on a continuous read acknowledge process and Ramses II and by inference III does not is also a small clue that they're different.
 
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And of course each manufacturer can have their own encoded signal set between transmitter and receiver, Ramses II and III will not the only ones.

If the OT current and voltage was transmitted by RF, quite a feat in itself, I would look for a Honeywell transmitter to connect to a Vokera, Salus, Delta Dore, Nest, Remeha, Baxi, Thebens receiver and vice versa.

I only have V4 of the spec here but this will not have changed from the earlier version
 

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You lost me...
That is not difficult. They could have used Ethernet for the protocol, but they never as they wanted a light protocol that is not resources heavy to process, so devices can have a small microprocessor inside them (like room sensors). All OpenTherm devices need a microprocessor. So Honeywell created a fast and small protocol with little overhead requiring little processing power and bandwidth, specifically for heating/cooling giving it away for open use for £1.

Look below. The Physical Layer deals with the physical hardware level. That is the bits received from the copper wires and RF signals - converting the bits into protocol frames. The DataLink Layer and Application layer are software only, in most cases being in a firmware chip. The DataLink layer receives data from the Physical Layer, processes it then gives it to the Application Layer. The application layer takes data from the DataLink layer then gives it to an app. It does not even know the Physical layer exists, not caring about that layer, only what is below and above. It is divide and rule.

3. Physical Layer describes the characteristics of the physical medium and the method for bit-level signalling.
4. OT/+ DataLink Layer describes the composition of OpenTherm/plus frames and allowable conversation formats.
5. OT/+ Application Layer defines data objects and the mechanisms for transfer of application data between the boiler and room controllers.

I have operated more network analysers, on many network types and protocols right down to bits and bytes levels, than what you have had hot dinners, believe me Dannyboy.

Many here, you included, do not know what a protocol is confusing it with the physical medium. View a protocol as a letter sent to a lawyer. It is received with another letter sent back to acknowledge receipt and that contents of the letter are not corrupted. If the contents are corrupted (say coffee split on the letter) the receiver (lawyer) requests a resend. The letter is opened by the lawyer then the contents (data) extracted and looked at. The lawyer analyses the data in the letter then sends a letter back to the sender, again the receiver sends a letter acknowledging receipt. If there is no acknowledgement of receipt the lawyers sends another letter. That is the basis of how protocols work. Exchange of information from one device to another.

So a boiler can communicate with a simple temperature sensor. Or with a full blown controller. Either way they are consonantly sending to each other. OpenTherm, as it is mainly on an enclosed system does not need so many acks, as a protocol moving over the Internet from country to country being processed by routers and moved into the data sections of differing protocols along the way. All this movement, and stripping down protocols (overheads) requires processing. OpenTherm in its basic form needs little as its network is stable and reliable.

If you want to learn drop the arrogance. You are a plumber for God's sake.
 
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If the OT current and voltage was transmitted by RF, quite a feat in itself,
Only the OpenTherm protocol is transmitted over an RF. The temperature sensing device gets data then puts it into a protocol (letter) forming it into a bit stream. The bits are put onto an RF signal. The base receiver/sender, receives the bit stream with a small microprocessor, as in the case of the T6R, depending how it it set up, either operating a small switching relay, or just sending the bit stream onto copper wires to the boiler's microprocessor on its pcb to process the OpenTherm protocol. The boiler does not care how the OpenTherm protocol got to it - it could have been around the world 10 times on differing RF signals, or on a wire that is only 1 foot long, for all it cares.
 
I am in lecture mode. Take note. Pay attention.
nwgs, you were lost years ago. :)
 
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