PIR am312

[TheoL]

@Dwalt if I understand it correctly, it monitors motion actively? So that it keeps the pin high as long as it keeps detecting motion?

Keep me informed, please. That way I can remove that part from my nodes.

[NeverDie]

@Dwalt
Did you ever find anything out regarding its true current consumption?

[acp]

Hi,

Sorry to bump this old Thread.
But i thought i give some Info in case anyone stumbles on it via searching am312+mysensors like i did some Weeks ago.

I used the banggood Module for a Battery Powerd Node.
At first it was running from 3xAAA Alkaline Batteries.
But after a Week Batteries where emtpy.

So i had a detailed look at the Node.
The PIR Module has a 3V regulator on Board, which seems to be designed for 5V input.

The Batteries only provided ~3,9V wich resulted in ~1,4V behind the regulator, but the Module was working properly.

So i decided to remove the regulator from the PIR Module and power it from 2 AAA Batteries (providing ~2,4V input).

Additionally i removed another 3,3V regulator i was using for the nrf24l01 Radio.

Now the Power consumption is down to ~0,2 mA while sleeping (ATMega328+NRF24l01+Pir Module) and ~15mA when awake.

Running without Problems since 2 Days.

[AWI]

I just received my samples of the AM312 and ( @gohan as promised) my observations/ measurements. (which are not in line with @acp observations above)

1. Rock stable. Even if I use the on-board regulator to also power a MySensors node it does not get into trouble (fires only when supposed to)
2. The hold-time is as specified in the datasheet 2.3 seconds
3. Power consumption: 14.2 µA! when idle 15.4 µA when active.
4. These boards can handle anywhere between 3.3 and 12 V power (ldo on-board).
5. I won't be using any of the small or modified HC-SR501 or similar BISS0001 based sensors anymore. These typically have 4 times higher power consumption/ very sensitive to all kinds of power and environment noise/ large/ but adjustable (can live with that and handle in software).

[NeverDie]

@AWI

Thanks for your post! What type of detection range are you getting out of it? i.e. within what range can you reliably detect motion?

[sundberg84]

@AWI - Could you see what happened below 3.3v? Ie, using 2xAA ?

[gohan]

I can't wait to get my pir sensors 😀

[NeverDie]

Me too. Based on AWI's report above, I just went ahead and ordered them.

[AWI]

@NeverDie It looks like its in specification. My "lab" is not that big... I could easily detect around 5 meters through the open door ;-)

[AWI]

@sundberg84 I turned the voltage down to 2.6V and it was still fully functional. Did not test noise sensitivity (disassembled the test set-up) The sensor is specified to 2.7V, the LDO (HT-7530) has a typical voltage drop of 100mV in normal operation.
Seems to be very small (< 5mV) when Vin is below 3V.
Conclusion: looks good for 2AA alkaline.:ribbon:

[NeverDie]

@AWI said in PIR am312:

@NeverDie It looks like its in specification. My "lab" is not that big... I could easily detect around 5 meters through the open door ;-)

FWIW, when I click on your specification link, all I get is "Access Denied". Is it just me, or can anyone else here click through to it?

[AWI]

@NeverDie The "specification" is a link back into this forum (https://forum.mysensors.org/topic/6658/pir-sensors/18) so you should be able to access it...

[kontrollable]

@NeverDie Same here, access denied!

[NeverDie]

@hek Seems there's a problem: a simple link back to forum is resulting in "Access Denied." Can you fix it?

[hek]

You are linking to thread in the moderators private area.

[AWI]

@hek @NeverDie @kontrollable My stupid mistake... :blush: I was referring to this from the datasheet Pir-AS312

[gohan]

but also it depends on the lens right?

[NeverDie]

Unfortunately, the link you posted (https://forum.mysensors.org/assets/uploads/files/1493990586841-pir-as312.pdf) reports file not found.

Since links aren't working, can someone upload the pdf of the datasheet to this thread as a file attachment?

[Edit: That's funny: After I posted the link, now when I click on it I'm now granted access! So, I'll attach it to this post now that I finally have it.]0_1494013513879_1493990586841-pir-as312.pdf
Hopefully others can now access the re-uploaded version.

[NeverDie]

For Halloween, it would be pretty amusing to have the PIR turn on some eyeballs like this:
https://cdn-shop.adafruit.com/product-videos/1200x900/3356-05.mp4
especially if you had about 6 of them scattered about.

[Nca78]

Missed this thread last week...
Just tested mine today with 3.3V supply and I have similar current consumption, around 15µA on my multimeter but the full board in sleep mode. It's staying active as long as there's movement detected, and seems stable: no interference from NRF24 radio when sending updated state to gateway.

But I have poor range, I'm not sure why, maybe the orientation of sensor/lens, or maybe the hot temperature, over 30°C, I will do more tests tomorrow if I can.
I tested with a not very well aligned fresnel lens from a SR501 I can detect at over 4m

I've got some AM612 too, with extra setting for active duration & sensibility, and an OEN pin to enable output based on analog signal (on datasheet example they use it with a photoresistor). If I believe the very similar detection profiles in the datasheets it's the same sensor but the AS312 has settings hardwired in the "can".

Not sure if 2 AA/AAA is the best solution, I would go for lithium cells. CR2032 would probably have too short battery life in a busy room (somewhere around 6 months) but bigger cells like 2477 or CR123 (>1000mAh) would last way over 1 year. Compared to AA they have the big advantage of staying over the 2.7V minimum value in the datasheet for most of their life.