Using Smart Implant to measure temperature with a 10 kOhm passive temperature sensor

[sahan.jenny 1]

Has anyone done this before. or know if this is possible? I have 4 of these sensors i need to hook up?

 

Alternatively, is it possible with another z-wave compatible device?

[pogo 3]

I don't thing those sensors are expensive enough to buy another z-wave device instead of new quite cheap DS18B20... You can buy 4 of them for about $5 I believe...

Why you think your 10kOhm are any better? Compatible device will cost You about $40-$60... if exists...

Edited November 12, 2021 by pogo

[Tim__ 110]

More info on connecting DS18B20 here

 

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and here

 

 

[Martin_N 143]

@sahan.jenny

Hi,
you threw yourself "on a thorny path ...".
NTC sensors can be used.
You have to make a simple voltage divider. I recommend a "pull-up" resistor to limit the current and adjust the voltage to a range that you can measure at the 0-10V analog input.
Then just write the voltage / temperature conversion table in QA (or in the scene).
Note that the table will be quite large and will depend on the required temperature range.
I suggest a step of 0.5 ° C.
In practice, I have already made such tables. Be sure to use the NTC datasheet, where you will find the Ohm / Temperature table. From the above, recalculate the voltage / temperature divider according to the needs.
Then in the mentioned QA (scene) you will periodically query the voltage value on the analog input, you will find in the table a line with the temperature corresponding to the given voltage (the condition will be you will find out between which voltage values the measured voltage will be).
Voala .. mate thermometer.
Watch out for a few trifles.
You will have to add temperature compensation, because the passing voltage will heat up the entire circuit depending on the current flowing ... if you have an NTC near the Smart Implant, it will also heat all the surroundings ...

1) study this topic, it can help you a little:

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2) The time required to read my contribution and the fiber provided by me will be paid for by any NTC laboratory if you immediately purchase a Dalas sensor on the 1Wire bus.

3) if this has not discouraged you yet and you want to play ... I keep my fingers crossed and share the result with us.

P.S. if you plan to have SI in the same place as NTC, you can ignore NTC. SI has internal temperature measurements.
I use it to measure the temperature in the rooms when I have SI under the switch.
In the internal SI settings, it is possible to make temperature compensation ...

eM.

 

[sahan.jenny 1]

so strange. i received no notifications of your replies, so assumed nobody had answered. thank you very much for answering though. 

 

the reason i had asked is cause i am getting a balanced ventilation unit with heat exchanger installed which already has 5 NTC 10k@25oC sensors intalled. I just received it and explored if i could replace the sensors with the digital sensors that work with the universal implant, but this is not possible without breaking things and i've decided i dont want to go that way.

 

So my options are to install my own qubino sensors in the ducting, or try to read the NTC sensors. I'll try to do both as this is as much a hobby as it is a functional thing. 

 

Unfortunately though i know it is a 10k @ 25 oC sensor, i did not get the full table. I'll see if the manufacturer of the ventilation unit is willing to share.

 

I also found that the HeatIt thermostat is able to take 10k external sensors. I was thinking that might be the simplest way forward. Anyone have any experience with this? Or aware of any other z-wave devices able to read this input?

 

Regards,

 

Sahan

[Martin_N 143]

@sahan.jenny

So, if you want to play and have it as a hobby, you can choose Arduino or ESP8266 / ESP32 with thermistors. From ESP you will read the values of JSON REST api help.
You will find a lot of examples.
Of course, if you have wi-fi in range.
If you want or need to stay on Zwave, see here:

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[sahan.jenny 1]

oooh. i'm very excited about this option. but you just exceeded my ability capabilities. 

 

i have wifi, but if i can make it work with just z-wave i prefer it. as having the information available within my Fibaro HC2 as a device just makes it easiest to integrate it with my scenes.

 

i have followed the link, and googled ESP8266 and ESP32 but unfortunately i have zero experience with circuit boards, or how to flash / program them... 

 

Are you aware of someone who has done this before and published it online?