Presence Sensor Device

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neb

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#3224203 29-Apr-2024 15:16

SirHumphreyAppleby: Assuming you're using the LD2410, these will work on 5-12V, so I would probably use a 12V power supply.

As a more general rule, if something can take a range of input voltages, always supply something on the higher end of the range. Running low-voltage DC through longer cables is a major pain, so going with the higher voltage means you're compensating for drop in the cable. If your 12V arrives as 10V that's fine, but if your 5V arrives as 3.5V it's less good.

This is also why many USB power supplies output 5.1 or even 5.2V, and why many switching regulators have cable drop compensation circuitry built in. Which the manufacturers of the Middle Kingdom then either ignore or copy the values from the data sheet, getting it wrong either way.

Username1

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#3224358 29-Apr-2024 22:52

I have the LD2410 connected to an ESP32. The furthest distance would be around 10 meters so I can run any kind of cable and a 12v power supply to a bunch of them?

neb

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#3224359 29-Apr-2024 23:04

That depends on the voltage and transmission speed, neither of which are given on the LD2410 web page. Assuming TTL-level serial signalling at 9600bps run over UTP, you should be OK for 10m. The faster the speed, the smaller the voltage swing, and the noisier the environment, the more problems you'll run into.

SirHumphreyAppleby

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#3227288 7-May-2024 11:28

SirHumphreyAppleby:

I'm not sure what the output voltage is. I expect it's the same as the input, but I need to confirm (I have cables and another five units on order).

In case anyone is interested, the LD2410 modules output ~3v (my voltmeter only displays whole numbers). The timer I wanted to use this with will trigger at 3V according to the specs, but annoyingly, it's not.

neb

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#3227420 7-May-2024 17:52

You could probably solve this with a level converter to get a larger voltage swing, Adafruit has these for various protocols. RS232, if that's what the protocol is, is valid from +/-3-15V and is usually run at 12V (with out-of-spec use at 5V), so it's not surprising that you're not having much luck running it at the barely-detectable threshold for signalling.

SirHumphreyAppleby

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#3227424 7-May-2024 18:07

neb:

You could probably solve this with a level converter to get a larger voltage swing, Adafruit has these for various protocols.

Once configured, you can just use the high/low output to determine if a person is within the desired ranges. I plan to use a cheap MOSFET board to switch the 12V supply and use that as the input to the timer.

ace310

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#3234109 24-May-2024 11:01

I have 2 of Tuya MTG075-ZB-RL in my kitchen/dining area and they work great. Lights are controlled by shelly 2.5. Both integrated in Home Assistant. They have light sensor which I use to trigger the lights based on the LUX value. It has worked 99% of the time.

I have just ordered esp32 & ld2450 from aliexpress and will be trying out the espresence on it. Lots of guides online on how to build one, here is a short youtube video with full guide. I am planning to add bh1750 light sensor to it as well once this works. Will get some nice enclosure 3d printed once I have the parts. ld2450 can detect 3 subjects which is what I am more interested in.

Best and Worst Presence Sensors

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SirHumphreyAppleby

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#3254966 1-Jul-2024 09:26

I'm ready to install a sensor above the front door. While I have successfully tested the radar with Gib and particle board, I've decided I will mount the sensor under a plate on the ceiling rather than trying to sense through fibre cement board. The ESP32 will be in the ceiling. I expect it would work through the cement board, but given how difficult the spot is to access, I'd rather not have to change it later.

The LD2410 library available through the Arduino IDE feels somewhat incomplete. I thought I could just configure the gate sensitivity to turn off the gates I wasn't interested in and read the remaining values directly. This isn't the case, so I ended up using the stationary/moving distance and energy measurements and limiting the range. The distances were not always accurate in the Hi-Link software, so I may need to modify the library or write my own code if I am unable to fine tune using the current configuration as I'm really only interested in the second gate (i.e. ~75-150cm below the ceiling).

ace310

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#3254969 1-Jul-2024 09:37

SirHumphreyAppleby:

I'm ready to install a sensor above the front door. While I have successfully tested the radar with Gib and particle board, I've decided I will mount the sensor under a plate on the ceiling rather than trying to sense through fibre cement board. The ESP32 will be in the ceiling. I expect it would work through the cement board, but given how difficult the spot is to access, I'd rather not have to change it later.

The LD2410 library available through the Arduino IDE feels somewhat incomplete. I thought I could just configure the gate sensitivity to turn off the gates I wasn't interested in and read the remaining values directly. This isn't the case, so I ended up using the stationary/moving distance and energy measurements and limiting the range. The distances were not always accurate in the Hi-Link software, so I may need to modify the library or write my own code if I am unable to fine tune using the current configuration as I'm really only interested in the second and third gates (i.e. ~75-150cm below the ceiling).

I have it working nicely with Esphome in HA unless you want it in Arduino. Lots of yaml configs on github.

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Handle9

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#3272916 17-Aug-2024 15:52

ace310:

I have 2 of Tuya MTG075-ZB-RL in my kitchen/dining area and they work great. Lights are controlled by shelly 2.5. Both integrated in Home Assistant. They have light sensor which I use to trigger the lights based on the LUX value. It has worked 99% of the time.

I have just ordered esp32 & ld2450 from aliexpress and will be trying out the espresence on it. Lots of guides online on how to build one, here is a short youtube video with full guide. I am planning to add bh1750 light sensor to it as well once this works. Will get some nice enclosure 3d printed once I have the parts. ld2450 can detect 3 subjects which is what I am more interested in.

Best and Worst Presence Sensors

How'd you get on with adding the ld2450 to esprescence? I'm in the process of putting espresence around the house for bluetooth tracking so if it's easy may add other technologies to some of them.

ace310

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#3272957 17-Aug-2024 17:47

Handle9:

ace310:

I have 2 of Tuya MTG075-ZB-RL in my kitchen/dining area and they work great. Lights are controlled by shelly 2.5. Both integrated in Home Assistant. They have light sensor which I use to trigger the lights based on the LUX value. It has worked 99% of the time.

I have just ordered esp32 & ld2450 from aliexpress and will be trying out the espresence on it. Lots of guides online on how to build one, here is a short youtube video with full guide. I am planning to add bh1750 light sensor to it as well once this works. Will get some nice enclosure 3d printed once I have the parts. ld2450 can detect 3 subjects which is what I am more interested in.

Best and Worst Presence Sensors

How'd you get on with adding the ld2450 to esprescence? I'm in the process of putting espresence around the house for bluetooth tracking so if it's easy may add other technologies to some of them.

I am using this bermuda integration. Basically added bluetooth proxy to my esphome yaml and used the integration. Not using espresence.

https://github.com/agittins/bermuda

Here is the full esphome yaml

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