@Koresh can you give us an ETA of the sensor? I'm looking forward to buy some :)

@Sander-Teunissen you can modify the motion sensor to work on 3.3V (see http://www.instructables.com/id/Convert-a-5v-PIR-Motion-Sensor-to-33v-for-ESP8266/)

same problem here:
minimal example worked and I figured out that assignment of an ID helps :)
Maybe I missed this point that I have to and that auto assignment doesn't work the way I thought.

Thank you for you quick response!
I tried to use the TTL directly and it works :)
But now I'm afraid that I could kill the arduino by doing this all the time.

The moisture sensor used here is a sensor of this type ebay article with a LM393 comparator chip.

Best regards!

Hi there!

I'm new to mysensors and wonder myself if it's possible to power up an external sensor (moisture, rain, etc.) only on demand just a few seconds before the readout.

As the most external sensors come with their own PCB / μC they drain battery. So my idea here was to power them up when I really need them with

• a transistor
• or a MOSFET

by pulling up the gate with a digital output of the arduino.

Do you have any experiences which MOSFET (and additional resistors, preferably not SMD) are well suited to switch the sensors on with an 3,3 V arduino mini pro TTL?

Many thanks in advance