FS20/FHT/HMS/EM/KS: Basic information.

[jrkalf]

* This topic is under construction *
Please reply to this topic to help shape this information sticky.
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General
FS20 is Home Automation Protocol and a name for domotics products created by Contronics GmbH.
It's designed like many other domotics implementations to make life in your home easier. It allows for simple radio controlled switching of appliances in your home. FS20 is cheaper then other solutions like zwave, bidcos, zigbee, onewire.

Contronics has designed solutions for both Plugged-in use (wall sockets) and to be build in behind the walls so it's invisible.

The domotics range it covers is quite large:

• General Power: Light and Electrical switching
• Heat Control & Energy savings
• Basic security control
• HMS protocol modules
• Miscellaneous

Availability
It's generally available in Germany where it's sold by a electronics company called ELV AG. You may order with ELV from abroad via their website. In a wider area it's sold by Conrad which has resales channels in various countries in Europe.

Protocol
FS20 in most situations contains a sending or a receiving module. Only a few models can do both.
In most cases it's unidirectional traffic without any feedback. So if the remote sends a ON or OFF signal, it doesn't get any feedback the command was received and processed properly. In most use cases this is more then enough of course as most actions within your house will have visual feedback anyway (lights turning on and off).

The FS20 protocol operates on the 868MHz band.

Technical german protocol explanation of the FS20 protocol: http://fhz4linux.info/tiki-index.php?page=FS20+Protocol

Protocol Security
FS20 isn't a very secure protocol. Only a small variety of devices have a security mechanism that prevents tampering from outsiders. For example: if you know someone else's house code (8-digits) and device code (4 digits) you'll be able to turn on lamps, or turn on electrical switches. These aren't protected. But items like the central heating system (FHT) does come with a 2 way sync protocol to prevent tampering from outsiders. There is no official statement (as far as I've found) stating why they chose this setup. The logical conclusion would be that a light switched on doesn't have that much effect and can do with lesser protection.

Protocol Range
As pointed out the protocol at some points isn't secure and it's only UNI-direction. Meaning the receiver can't send, so it won't send back if the action completed succesfully or not, or it even heard the sending signal at all. Visual confirmation of the functioning of a device in the early stages is required.
If you have "dead zones" in your setup, there are repeaters for sale to help you bridge the gaps. These devices are FS20 RPT-2:

As pointed out above, it may seem you can reach 100m range. Keep in mind that it's up to 100m. Inside a house the range will be far less with concrete/metal in the walls. A three story house may easilly require a repeater to bridge the distance between the ground floor and the third floor.

General Power: light and electrical switching
This can be done in various ways. FS20 has a variety of on/off switches and dimmers. Both as plugs you can put into the wall socket, or wall mount option that can be hidden from view. For example the FS20 ST-3 as plug-in device and the FS20 WS1 as wall mount device.

Another option for LED devices: FS20LD. A description and modification for these devices has been posted by KidE over here.
These devices are receivers only. They have to be programmed once, and then you can control them by a remote control device.

Heat Control & Energy savings
FS20 has a heat control system to more efficiently heat your home.
It includes using a thermostat, a radio-controlled flow-valve for the radiators and even a window/door sensor to sense when the room isn't closed.
Base of the heat control system is a device the FHT80-b (version 1,2 or 3). There are also options for using the FHZ1000-2 (not to be confused with the FHZ1000pc!).

Protocol security
The FHT devices do have an added layer of security to prevent outsiders from tampering with your devices. You have to pair the devices so only so they'll only respond to the device it's paired with.

This FHT80b device does various things:

• Temperature readings
• Humidity readings
• Controls the FHT8v radiator flow-valve.
• Controls a FHT8w boiler relais.
• Receives sensor information from the FHT8TF-2 window/door sensor. (it checks if the window or door is opened or closed).

Advantages:

• Control each room temperature individually and accurately by having a FHT80-b thermostat per room.
• You can couple up to 15 FHT80-b devices to a FHT8w.
• When the FHT80-b notices that a window or door is opened it will automatically send a signal to the radiator valve to close itself. This in return saves energy because you're not trying to heat up the world outside your room.
• Allows for timed programming for room temperatures (for each room individually!)
• A FHT80-b can be controlled by a PC-interface device like the FHZ1x00pc or a CUL/CUNO device.

Important:

• The FHT80-b device doen't directly control your boiler, it talks to the FHT8w which sends the boiler a signal to turn itself on/off.
• A FHT80-b can only control one room. It either sends a signal to all the FHT8v radiator valves to open themselfs up, or to close. A single FHT80-b can't individually control valves in seperate rooms.

Technical protocol information on FHT: http://fhz4linux.info/tiki-index.php?page=FHT+protocol.

Basic security control
FS20 can interface to various FS20 enabled sensory devices that can be used for basic security control.

In the previous section we've already spoken about the FHT8TF-2 sensor. It sends a signal to it's controlling peer to let it know if a door/window is opened or closed.

Another option is the shutter control devices they have. You can hook up a FS20 control module onto your electronic shutters to remotely control them. FS20 RSU for example is a small device to be built into your wall so it's hidden from sight, it's not the only device. Check the shutters section of the ELV site to see more examples.

Other examples of sensory devices are:

• FS20 PIRI-2 are motion sensor devices. Some are just on-off switches. They even have a dimmer version.
• FS20 ES1 Vibration sensor.
• FS20 IRL Infrared light beam. (think of a trip-wire setup)

Miscellaneous
Think we're done on the options? No, FS20 has some other control options as well:

• Rain sensors
• FS20 to Telephone bridge. According to ELV specifically used in situations where it's paired with the FHZ1000-2 system. To send or receive triggers within your domotics system. According to ELV video's it's also usable for receiving security triggers from basic security devices and dial preset numbers on those triggers.
• Light sensors
• IR to FS20 gateway
• Radio Panel a wallmount radio which can be remotely controlled via FS20.
• Doorbell system. With a separate Gong and Pusher.

HMS100 protocol modules
HMS100 is an added part to the FS20 protocol family with a very specific target for it's modules. You will notice an overlap with FHT80 devices, but they're not locked to this system and they can be directly used via FHZ1000-2, FHZ1x000pc or CUL devices.

• HMS100 WD Flood sensor.
• HMS100 CO Carbon-monoxide sensor.
• HMS100 TFK Window/door sensor. Not to be mistaken with the FHT80TF-2.
• HMS100 TF Temperature / Humidity sensor.

Computer Interfaces
A seperate section has been created for the computer interfaces. It can be found: HERE.

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Keep in mind with all the information above. It's a work in progress. If you have anything to add, or correct. Please leave a message below and it will be corrected.

[Digit]

Nice post, good overview of what it can and cannot do. But I have another opinion on:

In most use cases this is more then enough of course as most actions within your house will have visual feedback anyway (lights turning on and off).

So, if an action fails, you just hit the button again to repeat the action? But what if it's event driven? Oops.
And how about those times when there's no visual feedback? Holidays for example.

In my opinion, stating that visual feedback will suffice is a bit "short through the corner"

[jrkalf]

You're absolutely right about that, but it's how the protocol works.
There are solutions to this issue btw. I've got a dead zone in my house as well and I use a FS20 RPT-2 for that.
It's a simple repeater device repeating a command that was send.

I'll try to post more on that tomorrow, there seems to be a bit of a control part in that as ELV states that the signal won't be repeated beyond 2 repeaters, for example:

Sender --> repeater --> repeater --> receiver


Jelle

[jrkalf]

Digit, I've added some extra information inside the information post. With a picture even.
And yes, I've verified that the simple switch devices have a listening radio onboard only. They don't send back their status.

[richard naninck]

Two additions:

To get somekind of feedback, just install a repeater even if you don't need it to cover the distance between modules. A repeater just repeats the signal but the nice thing about that is that the FHZ1300PC receives its own message again hence creating somekind of feedback / status. I use it like this so I know that messages sent by the PC are indeed sent because the repeater got it and sent it back to the 1300PC. Keep in mind that a repeater only handles the FS20 modules and no FHT modules.

As for FHT's, you can only bind them with either the FHZ1300PC OR the FHZ1000. You can't bind them with both at the same time. I got 10 FHT80b's talking to my FHZ1300PC and the PC controls the FHT's, but also receives from the FHT's in case an FHT was controlled manually.

[jrkalf]

Two additions:

To get somekind of feedback, just install a repeater even if you don't need it to cover the distance between modules. A repeater just repeats the signal but the nice thing about that is that the FHZ1300PC receives its own message again hence creating somekind of feedback / status. I use it like this so I know that messages sent by the PC are indeed sent because the repeater got it and sent it back to the 1300PC. Keep in mind that a repeater only handles the FS20 modules and no FHT modules.

That in fact seems like no solution at all. the FHZ hears his own signal yet again, but it can't directly query the S4B / TC6 (wall switches) and ask them for their status. I know there's a part in the FHEM manual about sending a "set <device name> sendstate" but that can't be translated into a getstate of any kind. Hence the FS20 ST-3 or WS1 modules are only radio receivers. They do never send their status back.
It's not that bad, if you keep in mind you want to use a repeater to cover all the corners of your house.

As for FHT's, you can only bind them with either the FHZ1300PC OR the FHZ1000. You can't bind them with both at the same time. I got 10 FHT80b's talking to my FHZ1300PC and the PC controls the FHT's, but also receives from the FHT's in case an FHT was controlled manually.

I thought I had already covered that. I'll read it again and update it if needed.

I was amazed by your comment that the FHT system can't be relayed via the FS20 repeater. Although it's understandable.
Is there a repeater system as far as you know to cover that?
I know the FHT80b signal is bi-directional

[richard naninck]

If I covered your info twice I must have missed it somewhere. My bad.

FHT signals cannot be repeated and since FS20 only has one repeater device, I guess that's it.

You misunderstand what I meant by using a repeater to gain status. The FHZ1300PC has somekind of buffer. It holds outgoing FHT messages upto 3 minutes before sending. When sending too many messages, you get an overflow and the FHZ becomes really slow because it is pushing out the complete buffer but gets way behind while doing so. Also while sending a message using the FHZ, the message itself may get stepped on by an FHT or any other device producing messages. In short, there are chances that messages sent by the FHZ are missed. When introducing a repeater you atleast know if a message was sent correctly simply because you get the same message back by the repeater. While coding all this stuff you can do two things: Either you send a message telling a light should go on and then tell your software to light up the light OR you use the repeater to get that status. You press a button in your software remote (HouseBot term I guess) and the light should go on but there is no feedback of any kind so how is your software remote lighting up the lightbulb image? -> by using a repeater.... Hope you get what I mean now.

FHT80b's send large data packets 3 to 4 times per hour. Every two minutes you receive info about how far (%) a radiator motor is opened. You can imagine the amount of 868MHz traffic when introducing 10 FHT80's with 13 motors. It becomes a bit dence in traffic and collisions are very much a fact of life so you may miss a lightswitch every now and then. This becomes less of a problem when using a repeater in your system.

[KidE]

ok this feels like a trail and error case. Iĺl take my 3 x 100 meter extension cord if you arrange the beer

[jrkalf]

Count me in for such a party..
At the moment I'm ordering my fht80b set and CUL device

[richard naninck]

Third addition:

The FHZ1300PC uses the FTDI chip much like RFXCom and Plugwise and many others. That way you can address it using a standard rs232 COM port over USB. Before seeing data in for instance a hex terminal, you first need to send a valid message through the FHZ. If you don't it appears that the FHZ is not receiving anything..

Same goes for the FHT's. I first had all FHT's bound with a FHZ1000 and was surprised I didn't see any data coming from the FHT's on my FHZ1300PC. After restting the CEnt option to nA in the FHT, the FHT's binded with the FHZ1300PC instead of the FHZ1000 and data became visible.

Much of this info can be found online and some of it in the link posted in the first post. I just mention it here since those two things cost me much time to figure out.