<![CDATA[Possible to have an external power source for moisture sensors??]]>I want to run 6 analog moisture sensors on a single arduino nano(if possible). I am guessing that may cause erratic behavior from power issues. Is there a way to use an external power source and still provide a connection to the nano, like is done with a jd-vcc pin on my 8 channel relay, so the sensor will work correctly?

]]>https://forum.mysensors.org/topic/11411/possible-to-have-an-external-power-source-for-moisture-sensorsRSS for NodeSun, 14 Jun 2026 22:43:14 GMTTue, 20 Oct 2020 13:21:38 GMT60<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Mon, 26 Oct 2020 07:41:19 GMT]]>I have MySensors node with 5 moisture sensors - work without problems for one year.
Node platform:

  • Arduino Pro Mini 5 V
  • RFM69HCW powered by 3,3V voltage regulator + resistors on communication lines
  • 5x FDRobot moisture sensors
  • 3x DS18B20 temperature sensors

powered by 5V, 1A power supply

]]>https://forum.mysensors.org/post/107897https://forum.mysensors.org/post/107897Mon, 26 Oct 2020 07:41:19 GMT<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Wed, 21 Oct 2020 09:50:52 GMT]]>@mrhutchinsonmn So long as the ground wires are all connected together you should be fine.

But before you do a lot of work, search on here about moisture sensors, it might save you a lot of time.

]]>https://forum.mysensors.org/post/107868https://forum.mysensors.org/post/107868Wed, 21 Oct 2020 09:50:52 GMT<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Tue, 20 Oct 2020 19:41:20 GMT]]>@mrhutchinsonmn yes. Relays draw a lot of power when switching. Moisture sensors draw almost no power.

]]>https://forum.mysensors.org/post/107867https://forum.mysensors.org/post/107867Tue, 20 Oct 2020 19:41:20 GMT<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Tue, 20 Oct 2020 19:17:23 GMT]]>@mfalkvidd I was looking at it through the perspective of my 8 channel relay which needs an external power source to work reliably. Seems 6 moisture sensors will work fine.

]]>https://forum.mysensors.org/post/107864https://forum.mysensors.org/post/107864Tue, 20 Oct 2020 19:17:23 GMT<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Tue, 20 Oct 2020 19:12:52 GMT]]>I don’t see why it wouldn’t work, but on the other hand I don’t see the original problem either.

]]>https://forum.mysensors.org/post/107863https://forum.mysensors.org/post/107863Tue, 20 Oct 2020 19:12:52 GMT<![CDATA[Reply to Possible to have an external power source for moisture sensors?? on Tue, 20 Oct 2020 17:08:59 GMT]]>@mrhutchinsonmn Did some more research. It seems it is possible to run all 6 sensors on a single board without a 2nd power source since readings are not taken simultaneously. Is that a correct assertation?

]]>https://forum.mysensors.org/post/107858https://forum.mysensors.org/post/107858Tue, 20 Oct 2020 17:08:59 GMT