Im looking at getting some mmWave devices and there is such a huge amount of variation out there now,
Looking specifically at the HiLink HLK-LD1125H-24G. Is anyone using these boards and can advise on how they are performing?
Any other recommendations etc or things I should look out for before ordering?
Thanks
I’m in the process of experimenting with RCWL_0516. At work the product I work on uses a TI sensor. The MM Motion/Presence Sensors are highly sensitive. False positives need to be accurately managed. With the right False Positive rejection, and understanding increased penetration; I suspect these could be excellent Motion Sensors. My first application will be a down looking ceiling mount point to a concrete floor. Remember if horizontal in a room, you can get detections beyond the room parameters.
A lot of people use them and they are frequently discussed. You can find those earlier and usually still active mmwave threads by using the Search box. Also, you can look up each ones specs and compare them. One may suit my needs and not yours for your location or it may have secondary features that arent useful to most but, very useful to you. I highly highly recommend doing that research and not going on whatever is “popular” Your asking good questions and educating yourself though, thats a good sign and excellent to see!
On a side not, I would avoid using the RCWL-0516 like the other guy mentioned. He should probably complete his experimenting before making a recommendation. Those things are notorious for arriving and all of them being broken, having range issues, or interface issues. Even when you get one that actually works, its basically just as good as a PIR sensor. Trust me, i still have probably 10 of them that came DOA and i didnt feel like returning them and the hassle to get my 6$ back.
Spend a little extra and buy ld2410 or newer models. They’re 50x better than RCWL-0516 and unlike RCWL-0516, they actually work really well. I wouldnt waste your time or money…
I’m in the process of removing mine. I replaced four PIRs with 24GHz uWave sensors. The bloody things see through walls and false trigger the lights. Back to PIR for me.
They’re not for every house/building or even every room, thats for sure. A lot of times you can configure them to your liking but, thats not always possible either. I still use 80% PIR but, I think its good for people to try new things out.
Edit:
Unless its the RCWL-0516 those things are worse than a dumpster fire.
To be fair, I am happy with my PIRs for motion, its more specifically for room presence detection than anything.
Ha. No. These: https://www.aliexpress.com/item/1005005946930840.html
They do work well with Z2M and allow tuning of the range and sensitivity but they are quite wide angle so to get good coverage of the intended area I end up spilling through the side walls.
Also my robot vacuums trigger them, where as my “pet immune” PIRs don’t. They set off my security alarm the first time the vacuum schedule started.
I hoped two of them would be better at sensing presence in the “throne rooms” when “sitting and thinking”.
Nice! Ive got a porcelain thrown room too! Its where my best ideas come from…
Even with PIR sensors, it seems like I cant ever get things dialed in 100% Me personally. I wouldnt dare use a PIR as a single condition that triggers an action, especially an alarm. Not unless your trying to make enemies out of every police officer in town.
I never get false alarms with my PIRs. Except for one. It is in a room on the north side of the house so gets direct sunlight and tree shadows in the wind. I just don’t include that sensor in the alarm. This is another thing I was hoping the uwave sensors would fix.
As far as “IR only” sensors for alarm purposes goes: “real” ones have a selection, called “pulses” - basically you can adjust number of Fresnel zones a man must cross in order to trigger an alarm, normally you set that to 2 or 3. That makes them pretty reliable, but the only true solution is a combo sensor: combination of IR and MW: alarm triggers only if both technologies are triggered. No false alarms, works very reliably - no problems in ~20 years of working with alarm systems.
I tried those combo sensors outside where PIRs would false trigger a lot in changing sunlight. Unfortunately they still false trigger on moving trees that are creating the moving sunlight! I use cameras and object detection outdoors now. 100% better.
Out of curiosity: to me mmWave was a new kind of sensor, but as an electronic engineer I’m familiar with microwave theory (I don’t work,in the field though). Honestly want to know: Has the application of microwave tech to alarm systems existed longer than I’ve thought?
Yes, microwave in PIRs has been around for 10+ years, used widely in outdoor PIRs.
Dual-technology sensors are out for quite a while, yes, although first models were IR+ultrasound combo’s (picture - the big one, compared with modern combo and my hand). But MW combos are out for quite a while, too, yes, definitely over 20 years (when i started working with alarms 20 years ago they were already present)
tom_i: combo sensors are made for indoor or for outdoor use, they are different not only in weather protection, but also signal management is different. While you can’t (shouldn’t) install indoor sensor outside you basically can install outdoor one inside…
For outdoor you have also “a special ones”, like THIS one - it’s for windows, doors protection etc… it has 3 IR sensors in one case, alarm only triggers if all 3 detect an obstacle. We have a few of these installed (among others in the woods), and no one threw a single false alarm yet. Like i said, they generally require to pass at least two (or more) Fresnel zones to trigger an alarm, which practically no tree branch does, (unless it’s cm’s from the sensor).
Regarding sunlight: MW part is immune to sunlight (or quick/slow changes of it) so it won’t trigger an alarm if IR part is clear.
Ok, there’s always “but”…i guess if sun triggers IR part at exactly the same moment when tree branch almost breaks off…
Yeah I know, but as I said moving bushes/trees casting moving sunlight/shadows will still false trigger them. I tried a few (outdoor rated) and they all false triggered even with number of pulses set to max.
Personally, i think the best solution is simply self education. A lot of people say neither sensor will do and only a combination will work. I do kind of agree with that in a broad “answer for everyone” view. There really isnt any one size fits all answer IMO. I think a lot depends on the individual and number of people/pets in the home, the location, the user’s expectations and needs… I just dont think its as simple as saying “this or that” is what someone needs. I think it just depends and its not that difficult for anyone to experiment and find what works best for them and where it works, especially id they need borh sensors inorder to make 1. I say people should just experiment and find out for themselves.
