💬 Multi-Sensor: Temp/Humidity/PIR/ Leak/Magnet/Light/Accel

[ghiglie]

I'm quite a noob, but totally with the NRF. Interesting PCB, I'll try asap to put a sensor together!

[NeverDie]

I made one last change to add water leak detection to it. I just now uploaded the version 7 files. :)

[NeverDie]

I have the Version 1 design now working with the si7021 breakout board that I got from Aliexpress. Note that if you use these breakout boards, remember to remove the voltage regulator and solder bridge across the two pins as shown in the photo below:

This is because the coin-cell voltage is already in the desired range, and so there's no need for further voltage reduction.

[Toyman]

Is v7 already for CR2477? BOM still mentions CR2032

[NeverDie]

@Toyman said in 💬 Small Wireless Temp/Humidity Leak/Magnet/Light/Accel Sensor:

Is v7 already for CR2477? BOM still mentions CR2032

If I had kept the same button cell holder as some of the earlier version it would be. However, I switched to a narrower profile battery holder in the BOM (which benefits the leakage sensor part of the design). Not sure if an equivalent CR2477 holder is still available with the new design. Haven't checked. When I brought up the possibility of a CR2477 earlier, it didn't seem to generate much enthusiasm at the time. So, I took that to mean most people weren't really interested.

[krisha]

Nice project!

What about adding two resistors to measure and send the battery level as well?

[NeverDie]

@krisha said in 💬 Small Wireless Temp/Humidity Leak/Magnet/Light/Accel Sensor:

What about adding two resistors to measure and send the battery level as well?

not needed. You can measure the battery voltage without a divider.

[NeverDie]

I just now uploaded the Version 8 files, which contains pads for an optional 100uF ceramic capacitor. Thank you to @nca78 and @scalz for the suggestion.

[NeverDie]

Now reads temperature and humidity from the si7021 and sends the values to Domoticz for graphing:

[ghiglie]

...another n00b question: what are the PCB dimensions?

[NeverDie]

@ghiglie said in 💬 Multi-Sensor: Temp/Humidity Leak/Magnet/Light/Accel:

...another n00b question: what are the PCB dimensions?

The diameter is 27.15mm.

[ghiglie]

@NeverDie Thanks! I'll ask the fab if they can do it without charging extra costs. Or I'll "square" it - maybe with a hole in the angles to screw it. Really like this design.

[NeverDie]

@ghiglie What is it that you'd want to screw it to? It might be easier to just tape it or glue it in place. It's light enough that it wouldn't need much holding strength. Screwing may be overkill.

[ghiglie]

@NeverDie said in 💬 Multi-Sensor: Temp/Humidity Leak/Magnet/Light/Accel:

@ghiglie What is it that you'd want to screw it to? It might be easier to just tape it or glue it in place. It's light enough that it wouldn't need much holding strength. Screwing may be overkill.

I was thinking about the top of a door... You'r right, I overestimated its weight.

[NeverDie]

@ghiglie said in 💬 Multi-Sensor: Temp/Humidity Leak/Magnet/Light/Accel:

@NeverDie said in 💬 Multi-Sensor: Temp/Humidity Leak/Magnet/Light/Accel:

@ghiglie What is it that you'd want to screw it to? It might be easier to just tape it or glue it in place. It's light enough that it wouldn't need much holding strength. Screwing may be overkill.

I was thinking about the top of a door... You'r right, I overestimated its weight.

If you've never tried them, these things are great:
https://www.amazon.com/Command-Poster-Hanging-60-Pairs-17024-60ES/dp/B01FIK56Q4/ref=sr_1_3?ie=UTF8&qid=1510769859&sr=8-3&keywords=3m%2Bcommand%2Bmounting&th=1
They have a lot of holding power (more than ample for one of these sensors), and yet they can be cleanly removed without damaging the surface you hang it on.

3M also has a velcro-like version so that you can attach, then detach and re-attach as much as you want.

[NeverDie]

First, the good news: it works! :) I've uploaded photos of the version 7 board that I just today received and put together. It powered up without a hitch and started sending temperature and humidity values to Domoticz like a champ. The one caveat is that I will need to increase the board diameter by a couple of millimeters, as there presently just isn't enough proper physical separation between the supportive male leak detection pins and the CR2032 battery holder. So, I will do that, and I will post a version 9 after I have received and tested the improved boards.

[ghiglie]

@NeverDie Thanks! Here in Italy they's sold with another name, but it's still a 3M branded one. I'll look for a pack! :)

[NeverDie]

I have uploaded version 9. This should fix the physical clearance issue. Also, I upgraded the cap to be a 1206 220uF ceramic capacitor, as the cost is nearly the same as for an 0805 100uF capacitor. I should think that 220uF will offer plenty of reserve for the future when the battery ultimately develops a high internal resistance.

[NeverDie]

More good news: I today received the PCB for a revision of my PIR module that's meant to be compatible with this Multi-Sensor. I just now did a dry-fitting, and, indeed, it should all fit together just fine:

That means the entire PIR sensor can be quite small and compact! :)

[NeverDie]

For PIR capability, the multi-sensor can simply plug into this PIR module: https://www.openhardware.io/view/420/AM612-Passive-Infrared-Sensor-Breakout-Board