Thanks EVB;

1. Yes; Last test with a bare pro-mini 3.3v
2. I did that...

// Enable and select radio type attached
#define MY_RADIO_RF24
#include <MySensors.h>
uint32_t SLEEP_TIME = 900000;  // sleep time between reads (in seconds * 1000 )
int oldBatteryPcnt = 0;
#define FULL_BATTERY 3 // 3V for 2xAA alkaline. Adjust if you use a different battery setup.
void setup()
{
}
void presentation()
{
  // Send the sketch version information to the gateway and Controller
  sendSketchInfo("Battery Meter", "1.0");
}
void loop()
{
//    // get the battery Voltage
//    long batteryMillivolts = hwCPUVoltage();
//    int batteryPcnt = batteryMillivolts / FULL_BATTERY / 1000.0 * 100 + 0.5;
//  
//    if (oldBatteryPcnt != batteryPcnt) {
//      sendBatteryLevel(batteryPcnt);
//      oldBatteryPcnt = batteryPcnt;
//  }
  sleep(SLEEP_TIME);
}

Again : 4.2mA (no sleep )
So sad !

May I suggest you think about self discharging parameter in case of a reloadable battery and a long life time ?

@Yveaux
YESSSSSS !<
That was the last problèm to solve.
Back with my own MySensors routine all is perfect ! (8uA in sleep mode)
I am very happy now and I thank all those who assisted me.
You've made my day !
Gilles

In my mind: The longest the wave the better the result through the rain;
So: 1st US;
2nd radar;
3rd IR
(may be I'm wrong )

May I suggest you think about self discharging parameter in case of a reloadable battery and a long life time ?

@Yveaux said in Battery Powered Sensors:

.... All was ok, so what did you change (and why)

A the very beginning, hesitating with the procedure, I've probably burnt the Minicore bootloader in the programming ProMini without noticing it... That's the only explanation I see.

Finally, I found it….
A big thank you to all those who helped;
Here's my report in case it could be usefull to others (so, they will not waste as much time as I did)
All began with my FTDI refusing to work with the MiniCore library, returning this classic error code: "avrdude: error: could not find USB device with vid-0x16c0 pid-0x5dc vendor'www.fischl.de' product'USBasp' when I wanted to reprogram a ProMini.
So I opted for programming via another ProMini (Arduino as ISP)
The first ProMini was able to receive the MiniCore bootloader and then my sketch without any problem, but the followings did’nt....No error message was reported; I spent 9 days trying hundreds of times changing only one thing at a time... unsuccessfully.
But this morning I tried again using version 2.0.0 of Arduino’s IDE, and here I received an error message; "Impossible to recognize the Arduino as ISP" !!!!
Eureka.... I had the idea to inject the MiniCore BootLoader + the “Arduino ISP” sketch in the 2nd via the IDE Arduino 1.8.13 and then use this very 2nd one to program others; At that moment, everything became normal; The tests were ok and went to "sleep" so I loaded my sketch and everything is good now.
So: If you try to use Arduino as ISP with MiniCore Both Arduinos sould have been burnt with MiniCore BootLoader
Thank you again.

PS: Could the admin delete all my useless posts ?

Please, have a look at the time stamps:

More or less 10 seconds if sleep time >= 10 000 ms
Only a little more than 3 sec if sleep time = 2 000 ms
Could it help ?

@skywatch said in Battery Powered Sensors:

@Gilles-BILLARD I understnad your frustration - I have been there myself.

I suggest s simple node to test with, something like the door/window sensor with just one switch.

I did that right away and the result is....
All's OKay without sleep(xxx):

2021-04-10 17:38:22.898 Status: MySensors: Node: 52, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:38:22.899 Status: MySensors: Node: 52, Sketch Version: GB.3.0
2021-04-10 17:40:25.515 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:40:31.277 (GiBi-Home) Light/Switch (Security Sensor)

Présentation then 2 minutes until I change the input twice

But with sleep() included...

2021-04-10 17:34:12.251 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:34:12.251 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:34:22.491 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:34:22.486 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:34:22.486 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:34:32.561 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:34:32.556 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:34:32.556 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:34:42.631 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:34:42.626 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:34:42.626 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:34:52.701 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:34:52.696 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:34:52.696 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:35:02.772 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:35:02.767 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:35:02.767 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:35:12.842 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:35:12.837 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:35:12.837 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:35:22.913 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:35:22.908 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:35:22.908 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:35:32.984 (GiBi-Home) Light/Switch (Security Sensor)
2021-04-10 17:35:32.979 Status: MySensors: Node: 51, Sketch Name: Temperature Sensor Sleep
2021-04-10 17:35:32.980 Status: MySensors: Node: 51, Sketch Version: GB.3.0
2021-04-10 17:35:43.055 (GiBi-Home) Light/Switch (Security Sensor)

The same kind of reboot up to présentation()

So sad !
NOTA: The sketch is the one provided as an example in BinarySwitchSensor.ino sketch
I've just added sleep( 10000) a the very end.

@skywatch said in Battery Powered Sensors:

...........have you checked the baud rate the pro mini or uno you are using as a programmer - maybe it is 115200 and that is optimistic for a 3.3V board.

The programmer is loaded with standard Arduino ISP sketch (19200 default baud rate)

@skywatch

Radio : https://www.amazon.fr/NRF24L01-antenne-module-emetteur-recepteur-sans/dp/B01FLVTY3G/ref=sr_1_21?dchild=1&hvadid=80470576921758&hvbmt=be&hvdev=c&hvqmt=e&keywords=nrf2401&qid=1618066959&sr=8-21

@skywatch said in Battery Powered Sensors:

@Gilles-BILLARD It's in the sketch when you start serial interface. As an aside have you checked the baud rate the pro mini or uno you are using as a programmer - maybe it is 115200 and that is optimistic for a 3.3V board. Make sure the programmer is using 19200 just to be safe.

For inof I am using arduino ide 1.8.13 and musensors 2.3.2 with a £2 aliexpress serial prgrammer and have only encountered warnings about sck (which can safely be ignored)....

Ha, OKay; I've aslo supposed a pb from that, so I removed the sérial monitor and baud rate config.
And after the bootlaoder burning, the log is OKay.. the MEGA328P ID is also the good one and always the same for all 328

@skywatch said in Battery Powered Sensors:

I suggest s simple node to test with, something like the door/window sensor with just one switch.

I'll do that, but for my thermal sensor the test cannot be more simple

......burn MiniCore bootloader with 9600 baud, 3.3V, 8MHz INTERNAL, BoD DISABLED.

I don't have the choice for the baud rate; Where is it located ?

Then add the radio module (you can try another if you have it

I swaped everything I could. (The radio modules that was connected to the single functionning sensor included)

what radio modules are you using? - A link or photo might help, there are bad ones and fakes that could be a problem for you).

Bought from Aliexpress;

Load your sketch and try again.

I have done the whole process hundreds and hundreds of time

You can measure the current to the whole set up and then just the radio to see if radio is not sleeping. ....

Yes I'll do that...