I’ve bought an MQTT Thermostat. The included wired DS18B20 doesn’t fit my application, I want to include my own with a different wire and sheath. But I haven’t been able to find the pinout for the connector on the board for the chip.
Could someone please post the pinout for the thermometer connector on the board? Thanks!
No one has tried this before? Come on… Well, I can trace Vss, Vdd with a multimeter but still…
You’re asking in the wrong place. This unit is Martin Harizanov’s design.
Hmm, I think I am exactly at the right place for the question. I bought the thing in the OEM shop and this is section of the forum where OEM HW is discussed. I respect his work a lot but I don’t particularly care who designed the thermostat. If such a forum exist, please move my question where his designs are usually discussed. Thanks!
I think it’s evident that nobody frequenting this forum knows the answer to your problem, or they would have answered. Hence the suggestion to try the designer’s website.
Martin comes here occasionally, but you will probably have less time to wait if you approach him directly.
Well, it’s weekend after all so we don’t know yet who knows frequenting here. Whatever, till I get to instal it i’ll have it figured anyway. Out of lazyness I thought I start by looking for the info from fellow forum members who know the device.
It might surprise you to know that there is a page on Martin’s website with circuit diagram, pcb layout and all the supporting data. Hence my suggestion to look there. But as by your own confession you’re too lazy…
Yes, I have been there. It doesn’t have the information I seek. And it only has the 3-relay board info, not the single relay one sold at OEM. I haven’t even been able to find the board and sch. designs for the single relay device. Neither at Harizanov, nor at the OEM GitHub page. Only for the 3-relay one but the pages don’t have the pinout even for that. Hence I turned to this forum. I thought since I bought it at the OEM shop people might be knowledgeable about it. Going this route it shouldn’t be important who designed the board but I did know. Though I might post on his page later when it stops timing out requests.
Hi @kobuki
This is the correct place to ask for support for the Wifi relay. We support all items we sell via the OEM shop to the best of our ability:
Here is the CAD schematic of the 3 channel version of the wifi realy. The pin-out for the SD18B20 is the same on the 1 channel version:
The middle pin is data and the outside pins are Vcc / GND. If the PCB is not marked you should easily be able to identify GND by looking at the ground plane around the pin, you can double check using a multimeter.
I hope you don’t mind I’ve renamed this topic and moved it to the Wifi Relay section to make it easier to find.
Good luck 
@glyn.hudson: thanks for the info and also for moving the thread (I dunno why I haven’t found the relay thread). I again fixed the title to contain DS18B20 instead of DS28B20
@glyn.hudson
This needs to be put somewhere where it can be found and won’t get lost.
Thanks. I could swear it wasn’t here the last time I saw it, or it was the 3-channel diagram: http://guide.openenergymonitor.org/integrations/mqtt-relay/
But near the and of the page the image above is there.
The Schematic is on the docs page: WiFi MQTT Control Relay Thermostat - Guide | OpenEnergyMonitor
@Glyn,
“Physical Dimentions” > Physical Dimen S ions
Fixed, thanks 
