But to add some information: the RPi Compute Module is designed for industrial applications so expect it to be much more robust than the standard RPi. Regarding the eMMC memory, it is very difficult to find reliable information about the durability of a specific chip but it looks like eMMC uses MLC and SD cards TLC NAND flash. MLC flash supports from 3 to 5 times more P/E (program/erase) cycles than TLC flash. Be free to google more information
So i think the only way to find out is running specific stress tests.
Here is a suggestion: if there is any interest and we find a trusted community member to do an unbiased review of the Telegea Smart Hub, we would be glad to supply some free samples to run OpenHAB and try it with different deployment scenarios. Let me know.
Do you also sell the things shown above like the USB relay Board? Does it fit in your din rail case anderen is it Plug and Play or ist any configuration needed?
Just got notice for this thread, very promising. If still applicable I would really like to try one of those as well. Let me know if you are still interested for Some unbiased testers.
And keep up the good work.
Hi, I am using openHAB with a raspberry for more than 3 years with a lot of binding and devices and I would be interested to test and review your server hardware, if possible.
Thank for telling me whether you are interested !
Best regards
Jetblack (from France)
Wow, looks like this article on LinuxGizmos has boosted our popularity a lot. Thanks for your interest in reviewing the Smart Hub. I will see what I can do to send out some more test samples.
We only produce the Smart Hub, the other components are provided by third party.
The relay card in the picture is a Conrad 4-channel USB relay card. It is compatible with the crelay software, which detects the card automatically and allows to control the relays via command line (OH Exec binding) or HTTP API (OH HTTP binding). Other USB relay cards are also supported but the Conrad card provides DIN rail mounting.
Otherwise we also use this 8 channel relay card, which is connected to the Smart Hub via the I2C connector. Up to 8 cards can be daisy chained, providing a total of 64 relays (this should be enough even for the most demanding Smart Home scenarios). The cards relays are controlled via GPIO lines provided by the MCP23008 Linux kernel driver.
For temperature and humidity a good solution is a Modbus sensor connected via RS485 to the Smart Hub which permits long cables. Unfortunately these are usually quite expensive. The sensor from our demo plant is a low cost chinese sensor which is discussed in this forum thread.
But if you can wait, we will have our own Modbus temperature and humidity sensor based on the Sensirion SHT21. It will be available at a very reasonable price in about 1 month. We are currently testing these prototypes.
Ok Thank you, let me know if it will be possible to test and review your board. I have a question : I use 10 1-wire devices with about 50 meters of wires. Does your integrated 1-wire interface withstand such a load ?
Thank you !
The 1-wire interface the Smart Hub provides is the bit banged 1-wire protocol via GPIO pin. It has in integrated pullup of 4.7KOhm on the data line and 3.3V power supply for the bus. We have tested it successfully with up to 300m cable length and 20 DS18B20 temperature sensors. Depending on the actual cable length you need to add an additional 4.7K or 2K pullup.
This is exactly what we have planned. Being focused on energy efficiency, we need to be aware of room occupancy to avoid heating empty rooms. So adding a motion sensor seems like a good idea. Light level can come in handy, of course.
You may have noticed that our Modbus sensor is composed of 2 PCBs. The bigger one contains the power supply, the PIC and Modbus handling while the smaller has the actual sensor component mounted. This way we can easily add new sensors. So there is surely more to come.
I’m a big fan of having physical switches for my lights as a backup, I see you have a few examples of relay boards you can link up to… But you got any ideas of how to increase the number of available inputs to cater for 16 or 32 switches around the house? Maybe a relay board that has 8 relays and 8 inputs and then being able to link up to 4 of them?
Next challenge will be making it so that some of the relay boards can be located in another circuit breaker box elsewhere in the house. So being able to attach one of these relay boards to the smart controller but on a long cable somehow.
The SmartHub has 6 GPIO pins available on the screw terminals and another 4 on a jumper block. At the moment the only possible solution I see to increase that is using a third party Modbus module with digital inputs, connected to the Smart Hubs RS485.
Here also a Modbus relay card would do the job. We don’t provide these at the moment but if there would be demand for this we could develop our own solution.
