Clean looking sensor node

[NeverDie]

@Cliff-Karlsson said:

I really like the pcb´s you are using @NeverDie, is it possible to buy them anywhere?

I'm just doing this for fun. If you want to buy something pre-made, I'd suggest buying a Moteino.

[Cliff Karlsson]

@NeverDie
Ok, but is the PCB availible at OSHpark or is the files availble for sharing?

[NeverDie]

@Nca78

Are you sure there's space for the coincell holder? The case is pretty thin. I ordered some tabbed coincells, but am still waiting for them to arrive.

[NeverDie]

@Cliff-Karlsson
Maybe later. I'm still improving the design.

[NeverDie]

@Nca78 said:

That's why I selected it, best suited for temp sensor.

Just received the first version of the PCB but it will need some improvements.
But looks like it will work, not too bad for my first PCB ever

Here's a newer evolution of my small TH node that includes a co-planar antenna. So, no long monopole antenna sticking out of the case.

I haven't attached the TH sensor yet because I've run out of them, but I'm pretty sure it will fit.

[NeverDie]

@nca78
What's the best way to remove the cover on this thing? Do I just go for it with a pry tool, or is there a special trick to it?

I'm hopeful it will fit a CR2477 tabbed battery, but it would likely be a very close fit if it does. In case it doesn't, have you come across any options that are a bit thicker?

[NeverDie]

@NeverDie said:

One possible concern with this particular example is that it has a metal band around it. That's not so ideal for an RF node, but it may not matter, as I tested the PCB node (just by itself, without the solar puck) within a closed refrigerator and still got adequate signal from it.

I tried running one of my nodes inside the solar puck that has the metal band (above). It's maybe a few dB worse, but the link budget is large enough that it just doesn't really matter. So, I think it remains a viable option as an enclosure for thicker nodes that don't easily fit inside the OP's thinner recharger puck.

[Nca78]

@NeverDie said:

@nca78
What's the best way to remove the cover on this thing? Do I just go for it with a pry tool, or is there a special trick to it?

I'm hopeful it will fit a CR2477 tabbed battery, but it would likely be a very close fit if it does. In case it doesn't, have you come across any options that are a bit thicker?

Sorry no magic solution to open

For the cell it should fit a 2477 but you need a thin PCB + thin holder.
Box is 10.6mm high minus 1.2mm thickness for the cover and 0.8mm PCB it leaves you with 8.6mm. 2477 is 7.7mm so you have 1mm left, not much but I think just enough if you use basic holder that's just made of a folded metal sheet.
But for such a basic sensor you would not need such a huge cell, CR2032 should last a very long time already, and 2450 could match your need of extra long lifetime and at the same time easily fit in the box. If your sketch is programmed correctly by the time a 2450 is dead the sensor will probably have become completely off because of aging

[NeverDie]

I received the Q8 wireless charging pad (above):
http://www.ebay.com/itm/Q8-QI-Wireless-Charging-Pad-2-USB-Port-Splitter-HUB-Charger-Pad-For-Phone-F5/301913729117?_trksid=p2047675.c100623.m-1&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D39345%26meid%3Decb1959e8f164eb5ad0a17aeaa297f59%26pid%3D100623%26rk%3D3%26rkt%3D6%26sd%3D252485416371

However, it is even thinner than the OP's vented puck, and it's about double the square inches of foot print. So I don't see any real advantage to them.

[NeverDie]

For a thicker case, Amazon Dot looks like it might be very nice:

A bit pricey though!

[Nca78]

@NeverDie said:

I received the Q8 wireless charging pad (above):
http://www.ebay.com/itm/Q8-QI-Wireless-Charging-Pad-2-USB-Port-Splitter-HUB-Charger-Pad-For-Phone-F5/301913729117?_trksid=p2047675.c100623.m-1&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D39345%26meid%3Decb1959e8f164eb5ad0a17aeaa297f59%26pid%3D100623%26rk%3D3%26rkt%3D6%26sd%3D252485416371

However, it is even thinner than the OP's vented puck, and it's about double the square inches of foot print. So I don't see any real advantage to them.

I have ordered one also (In fact two as aliexpress payment messed up and asked me to process payment again, but few days after I realized the "failed" payment was in fact processed and sellers were sending everything twice...).
I'm planning to use one as gateway box with wemos d1 mini and smd pa/lna NRF24 side by side. Any chance it will fit this type of ESP board inside or it's too thin and I should go for ESP12 module instead ?

[NeverDie]

@Nca78 said:

@NeverDie said:

I received the Q8 wireless charging pad (above):
http://www.ebay.com/itm/Q8-QI-Wireless-Charging-Pad-2-USB-Port-Splitter-HUB-Charger-Pad-For-Phone-F5/301913729117?_trksid=p2047675.c100623.m-1&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D39345%26meid%3Decb1959e8f164eb5ad0a17aeaa297f59%26pid%3D100623%26rk%3D3%26rkt%3D6%26sd%3D252485416371

However, it is even thinner than the OP's vented puck, and it's about double the square inches of foot print. So I don't see any real advantage to them.

I have ordered one also (In fact two as aliexpress payment messed up and asked me to process payment again, but few days after I realized the "failed" payment was in fact processed and sellers were sending everything twice...).
I'm planning to use one as gateway box with wemos d1 mini and smd pa/lna NRF24 side by side. Any chance it will fit this type of ESP board inside or it's too thin and I should go for ESP12 module instead ?

I just now measured the D1Mini, and it's about 6.7mm thick. If you removed the USB connector, it would be thinner.

I haven't opened the QB wireless pad, so I don't know how much depth is available. However, the case itself is 8.5mm thick. In comparison, I measure the case thickness of your OP puck as 11.7mm.

[Nca78]

@NeverDie said:

I haven't opened the QB wireless pad, so I don't know how much depth is available. However, the case itself is 8.5mm thick. In comparison, I measure the case thickness of your OP puck as 11.7mm.

Thank you. Sounds like it won't fit
For Amazon Dot yes it looks great, but 50$ is a bit too expensive for a case

[NeverDie]

I notice that Kalia made his own uniquely shaped enclosure that he 3D printed himself:

(for more detail see his posts under: https://forum.mysensors.org/topic/1566/mysensors-sensebender-micro-3dp-case/18)

I'm not yet savvy about 3D printers, but from what I've been reading lately the line artifacts in the plastic may vary in how prominent they are depending on the quality of the software slicer that's used to produce the g-code that's sent to the 3D printer. Still, I'm not sure to what extent it's avoidable or just a reality of 3D prints. Would such line artifacts always be visible, regardless of which printer or software produced it?

In any event, I like the way Kali molded the battery holder into the case itself. Very clever!

[mfalkvidd]

@NeverDie the lines will be more or less visible depending on layer height (which varies by 3d printer model) but can easily be made totally smooth. See this video

Cold Acetone Vapor Finishing for 3D Printing – 03:02
— doodaddoes

[NeverDie]

@mfalkvidd said:

@NeverDie the lines will be more or less visible depending on layer height (which varies by 3d printer model) but can easily be made totally smooth. See this video

Cold Acetone Vapor Finishing for 3D Printing – 03:02
— doodaddoes

Funny that in the video the demonstrator uses a polypropylene chamber, as I'm pretty sure acetone will strongly react with it. Aside from that, though, it was a good video. Thanks for posting it!

He seems to imply this acetone vapor chamber approach only works on ABS printed models. Is that correct?

Also, what must the 3D printer's layer height be for the lines to no longer be visible (without resorting to acetone vapors)?

[NeverDie]

Looks as though my small TH mote will have no problem fitting inside the OP's enclosure:

I can also configure my medium TH mote to also fit. The enclosure is too thin to accomodate AAA batteries, but I should be receiving the button cell batteries from China very soon.

[Nca78]

@NeverDie said:

Looks as though my small TH mote will have no problem fitting inside the OP's enclosure:

I can also configure my medium TH mote to also fit. The enclosure is too thin to accomodate AAA batteries, but I should be receiving the button cell batteries from China very soon.

Don't forget a capacitor parrallel to the button cell battery if you want it to last more than a few days

[NeverDie]

@Nca78 said:

Don't forget a capacitor parrallel to the button cell battery if you want it to last more than a few days

That's good input, as I haven't yet tried running it on a button cell. Is a button cell alone just not able to keep up with the Tx load? I had wanted to avoid button cells altogether, but even an AAA battery has too wide a diameter to fit in this enclosure.

[NeverDie]

It might be worthwhile to make a board specifically for this enclosure. It would necessarily have to have a somewhat similar size as the board that was in it, so that it could mount an LED near the LED window, and a micro USB at the USB window, all while fitting the groves of the enclosure.

BTW, how did you get that sticky black foam tape out of it? I tried scrapping it off, but I didn't manage to remove all of it.

[Nca78]

@NeverDie said:

That's good input, as I haven't yet tried running it on a button cell. Is a button cell alone just not able to keep up with the Tx load? I had wanted to avoid button cells altogether, but even an AAA battery has too wide a diameter to fit in this enclosure.

No it can't keep up with it without a serious voltage drop, especially at startup and with RFM radio. A 100µF ceramic capacitor (and sleep between successive tx in your code) should be enough from what I read from scalz who made a few boards with button cell + RFM.

I just uploaded version 0.2 of my dedicated board to Seeed, it should be just the right size this time Led is in front of the led window but on USB side I don't have anything, it's just a vent.
For the black tape I don't remember having so much pain to remove it, maybe it's different between enclosures, I will tell you when I receive the next one.

[NeverDie]

@Nca78

It would be nice to keep the usb port as an aid in reprogramming it, so that the case doesn't have to be opened or without having to do wireless OTA programming of it. Alas, it's probably feature creep.

[NeverDie]

On my medium node, I found that if I used right-angle FTDI header pins and if I splayed the antenna and the Temp-humidity-pressure sensor out horizontally, then the overall thickness was low enough that I could fit it inside the OP's enclosure.

Also, I think that if, rather than clipping the LED's legs after soldering it close to the board, I instead left the LED legs long, then I could bend it over and have it pointed at the LED window on the OP's enclosure, to maximize its visibility outside the closed enclosure. So, on a future version, I'll try that.

[NeverDie]

After a long-wait, I received my so called "tabbed" CR2477 batteries today from China via AliExpress. According to the seller, they would look like this:

and so that is what I was expecting. Instead, what the seller sent me was:

which obviously has no tabs.

Anyhow, the second photo shows the depth of the battery in relation to the OP's case. It looks to me as though with tabs it likely would have been too thick for the cover to snap back on the OP case.

[scalz]

@NeverDie
not cool
I hope your 2477 will work well
my little xp about coincells showed me that i can't trust ali coincells.. well i tried only few orders, but those wasted my time searching for bugs whereas batt were discharged and didn't check this in first place as i was using fresh ali coincells. I was thinking it couldn't be that! Then i checked their voltage in case...and was surprised!
Changing for good and strong coincell was day&night.

if it can help you to not run in dumb issue, for future

[NeverDie]

@scalz said:

@NeverDie
not cool
I hope your 2477 will work well
my little xp about coincells showed me that i can't trust ali coincells.. well i tried only few orders, but those wasted my time searching for bugs whereas batt were discharged and didn't check this in first place as i was using fresh ali coincells. I was thinking it couldn't be that! Then i checked their voltage in case...and was surprised!
Changing for good and strong coincell was day&night.

if it can help you to not run in dumb issue, for future

Urban Dictionary: "get shanghaied"
www.urbandictionary.com/define.php?term=get shanghaied
Top Definition. get shanghaied. verb, ditransitive, passive (with to Be or to Get). to be swindled, cheated, lied to, robbed, stolen from, duped, conned, deceived.

Not sure what I'll do with the "non-tabbed" batteries. Shipping costs between the US and China are asymmetric, and it would probably cost me more in time and money to ship them back with tracking to the seller than I would get in a refund. Oh well, I guess I'll be buying batteries from Digikey in the future. It will cost twice as much, but at least I'll get the real thing.

[scalz]

@NeverDie
ahah, this one is funny

[NeverDie]

I just now ordered this CR2460 battery from Digikey: http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=212190252&uq=636150784616350020

It's a bit thinner and should have a better chance of fitting inside the OP case.

[NeverDie]

Epilogue: I get a call from Digikey to tell me that they can't ship the button cells by first class mail because they contain lithium. Mind you, I only ordered 3 of them. Instead, they can only be shipped by either UPS ground or FedEx ground, both of which will cost me about $10 for the shipping alone. Yet, USPS apparently had no trouble delivering the CR2477 button cells from China using ePacket delivery. Argh, it's all just ridiculous!

[mfalkvidd]

@NeverDie no, USPS are not ok with that. http://pe.usps.gov/text/pub52/pub52c6_004.htm#ep270347

[NeverDie]

@mfalkvidd said:

@NeverDie no, USPS are not ok with that. http://pe.usps.gov/text/pub52/pub52c6_004.htm#ep270347

Not that it matters, but I wonder why is it acceptable for lithium batteries to be shipped installed in equipment, but unacceptable if not installed?

[mfalkvidd]

@NeverDie my guess is that the rulemakers took a pragmatic approach. Banning batteries in equipment might have been too hard, which could have brought down the entire proposition. So they opted for rules that are less safe than total ban, but more safe than no rules at all.

[Nca78]

My two cents

Batteries inside equipments are protected from shock by said equipment, shocks/bending beeing one of the main reasons for battery fires.

It could also be related to the "density" of batteries. Having one battery burning inside an equipment will slow down the propagation of the fire and is relatively easy to deal with a fire estinguisher.
Having a fire in one battery that will propagate to other batteries shipped together is a nightmare.

But I'm surprised they apply this rule (that I thought were made to deal big rechargeable batteries) to a bunch of button cells

[NeverDie]

LOL. This is the ultimate catch-22: I can't mail the falsely advertised batteries back to China, even if I wanted to! The only way to do it would be to first install them in some equipment and then ship the equipment, but then they would be used batteries and no longer new, so the seller could refuse a refund on those grounds. Since returning them is impossible, maybe I can appeal to Ali Express for a refund without returning them. This is becoming entertaining.... A refund from Ali Express would almost cover the cost of shipping from Digikey.

[hek]

They sent the wrong stuff. Opening a "case" will most probably get your money back.

[Nca78]

I just received the white version and it's gorgeous ! Ordering bunch now to put everywhere in the house

[NeverDie]

@Nca78
Would you please post a link for the white ones? All I recall ever finding were the black ones.

[Nca78]

Link is here but unfortunately it says "no more available"

https://www.aliexpress.com/item/Factory-price-Qi-Wireless-Newest-Charger-for-iPhone-for-Samsung-Galaxy-S4-S5-Note3-for-Nexus/32637381497.html

Found some here at 3€ :
https://www.aliexpress.com/item/Qi-Wireless-Newest-Charger-for-iPhone-Samsung-Galaxy-S3-S4-Note2-Nexus-All-free-shipping/32735986077.html

and here 3€38
https://www.aliexpress.com/item/2016-New-Fast-Charge-Qi-Wireless-Newest-Charger-for-Samsung-S4-S5-Note3-Cell-Phone-Accessories/32669922722.html

[Nca78]

And same seller has one it seems, at 2€78, but only interesting if you buy 1 item to get free shipping, else the one at 3€ is cheaper as there's no limit in item count for free shipping option

https://www.aliexpress.com/item/Best-Price-Qi-Wireless-Newest-Charger-for-iPhone-for-Samsung-Galaxy-S3-S4-Note2-for-Nexus/32647646301.html

[Nca78]

@NeverDie I found a good way to open them without any damages.
I have that cheap DIP chip extractor that's very bad at doing it's job, but it happens that it's the perfect size to fit in the vents at the bottom, if you put it inward and pull you can pop up the bottom cover easily.

I bought 10 white chargers from the "woweinew" shop for 30$ with China Post Registered Air Mail included after a few seconds of negociations.

I also found some SMD 7021 breakouts with only minimum components onboard, they are a bit more expensive but save some space in PCB surface and thickness. And no need to waste time removing and shorting the voltage regulator.
https://www.aliexpress.com/item/Industrial-High-Precision-Si7021-Humidity-Sensor-with-I2C-Interface-for-Arduino/32524005324.html

[NeverDie]

Just FYI: it turns out you have to avoid exposing the si7021 sensor to high humidity (>80%) unless you turn its buiilt-in heater on--which, unfortunately, will drain a battery rather quickly. It's in the datasheet, but not as prominently as it should be. Therefore, going forward, I'm switching to the BME280, which costs more but appears not to have this issue. I do have some si7021's, but I think I'll probably only trust the temperature reading and consider the humidity reading as a rough gauge only.

[NeverDie]

@Nca78 said:

Link is here but unfortunately it says "no more available"

https://www.aliexpress.com/item/Factory-price-Qi-Wireless-Newest-Charger-for-iPhone-for-Samsung-Galaxy-S4-S5-Note3-for-Nexus/32637381497.html

Found some here at 3€ :
https://www.aliexpress.com/item/Qi-Wireless-Newest-Charger-for-iPhone-Samsung-Galaxy-S3-S4-Note2-Nexus-All-free-shipping/32735986077.html

and here 3€38
https://www.aliexpress.com/item/2016-New-Fast-Charge-Qi-Wireless-Newest-Charger-for-Samsung-S4-S5-Note3-Cell-Phone-Accessories/32669922722.html

The first link has them back in stock. I just now ordered one from them.

[Nca78]

@NeverDie said:

Just FYI: it turns out you have to avoid exposing the si7021 sensor to high humidity (>80%) unless you turn its buiilt-in heater on--which, unfortunately, will drain a battery rather quickly. It's in the datasheet, but not as prominently as it should be. Therefore, going forward, I'm switching to the BME280, which costs more but appears not to have this issue. I do have some si7021's, but I think I'll probably only trust the temperature reading and consider the humidity reading as a rough gauge only.

Yes I have seen that but I wonder how much the "drift" really is. As long as the temperature is still precise (and it is from my observations) a drift in humidity measurement is acceptable, as long as it can still reflect changes. I've also ordered BME280 (6 pins version with no voltage regulator) from 2 different suppliers anyway, so I will be able to compare sensors side by side with every other part coming from the same batches.

[NeverDie]

Great. I'd be interested to hear of any conclusions you might reach from whatever comparisons you're able to perform.

[Nca78]

At the moment I have still not received my BME280 sensors so I'm testing with the si7021 only.
For the first step I have put 3 of them on top on each others and checked their reported values over nearly one week.
I must say I'm very impressed by what I have seen at the moment, the maximum temperature span I have seen was 0.3°, and 3% for humidity.
Now I can confirm the sensors report the same values, I'll move one of them in the children's bathroom where it's supposed to have the maximum humidity exposure. If reported humidity is high enough (>90%) I'll leave it there for 2 weeks then move it back together with other sensors and see if it got a shift in humidity measurement.

Typical display in Domoticz: very reproductible values between the 3 sensors.

[NeverDie]

Sounds like a good experiment.

[Nca78]

So unfortunately when I started this test it was "dry" season so even in batchroom it didn't prove very conclusive.
Had problem with battery life also due to bad settings + power cuts. Limitless reconnection time before going to sleep was fatal with 4h+ power cuts

Just reprogrammed them today and put them back in place, 2 @1MHz with CR2016 and 1 @8MHz with CR2025.
Rainy season is back and I have high humidity values on the 3 of them, 91% in bathroom right now so I should be able to run the test.

[hautomate]

These chargers are looking really good... Great job on this!

Has anyone used these garden lights? They look like they'd be ready to go as a PIR/multi-sensor considering there's already a AA holder and plenty of room under the lens. Maybe they could be tucked up by the ceiling. It wouldn't quite be flush because of the sloping top, but it may not be bad.

Searching around I see at least two different variations--one has a smoother, cleaner look to the lens and the other looks more "knobby." Some come with a battery and some do not.

A bunch of lights

With battery

Without battery

[Nca78]

@hautomate well it doesn't look so great imho.
There's no space for PIR lens so you have to make one yourself, it looks like hard plastic and it won't be easy to drill without generating any cracks.
No holes to put other types of sensors like temperature/humidity/... so same problem. In addition if you put it under the sun to charge, the temperature inside will not allow any measurement of this type.
Charging circuit is primitive, it's probably the same IC than in the 1$ garden lights and it just puts voltage to the battery +/- without any control of voltage: not a good way to maintain a good health for the battery.

So in the end you have a box that you need to modify to make it a sensor (except maybe a light sensor), you have a solar panel that provides a too low voltage so you need a step up converter, you have a charging circuit that's too bad to use and that in the end won't make the rechargeable battery last longer than 2 AA... Rather expensive for a plastic box

[NeverDie]

Also, at least based on my experience with cheap Chinese solar garden lights, the battery connections (and probably a lot of other parts too) will rapidly corrode/rust and fail soon after. Sorry if that sounds negative, but I see nothing to suggest otherwise in this instance. So, if you do decide to try it anyway, I suggest you try just one and see how it handles your weather first.

That said, my wife bought some solar garden lights at Costco earlier in the year, at about $8 each, and so far they're holding up and are working very well.
However, in that case, you've got an institutional buyer (Costco) with an interest in quality handling the due diligence on build quality and with a very generous and easy return policy. On Aliexpress, that just doesn't exist.

[hautomate]

@Nca78

Yeah, I hear ya...

I'm thinking indoor use here and not using the solar panel or circuitry for anything--just use the plastic and lens and pack it with PIR and temp/humidity. Mounted up high on a wall, any holes could be drilled on the top as that side wouldn't be seen.

I'm going to try one out...

[wallyllama]

Finding things to make into cases is fun. Here is my raspberry pi.

[Al Wolkow]

This post is deleted!

[Nca78]

@nca78 said in Clean looking sensor node:

Typical display in Domoticz: very reproductible values between the 3 sensors.

So some follow up on the sensors comparison. I'm still using the same sensors, unfortunately my son threw his behind (I think) his wardrobe so I cannot access it. But I put the 2 others side by side in the fridge, waited 20 minutes after closing the door and after 3 years of use they are still impressively consistent !

[Nca78]

And after getting out of the fridge, side by side, only a reasonable difference in humidity level. ( and yes, the weather is unconfortable today )