Damaged Soil Moisture Sensor Upgrade

by Challon in Circuits > Sensors

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Damaged Soil Moisture Sensor Upgrade

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I hope this simple instrucable will help some folks out there like me who like to use these cheap soil sensors in their projects. I found that over time the sensor will corrode and become of no use, so I decided to upgrade them so to speak with some simple 24 gauge stainless steel wire to make them last even longer after they have become useless. This simple upgrade has given a lot longer lifespan to these cheap sensors.

Notice in the image that one side has corroded to the point that the sensor is no longer usable.

Tools and Material Needed.

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  • Tweezers, Small Flat Head or Scratching Awl
  • Stainless Steel Wire (I use 24 gauge) found on Amazon pretty cheap.
  • Wire Cutters
  • Soldering Iron and Solder
  • Old Soil Moisture Sensor
  • Clamp and Fan - Hold the parts while soldering and also help draw away the solder fumes.

Scratch & Awl

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I take and scratch away the coating just above the sensors exposed metal strips that corrode with time. While I didn't calculate or do all the math involved to be certain the readings would be super accurate after the upgrade. The sensors still work like before and I've had them last for many months now.

Cut and Tin

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Cut and tin the wires on one end and then straighten them as best as possible. Does not have to be perfect. Do your best. :)

Tin the Pads

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Now lets tin the pads we scratched off earlier and solder the new stainless steel wires we just tinned to the sensor.

Cut and Done.

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Now that we have the new wires added to the sensor we can cut off the additional wire hanging over the ends and you're done.

I have successfully been using these types of upgrades on sensors for months now. The original sensor depending on how ofter you probe for data will usually only last a month at best if you do not change the polarity in your code every once in awhile. Regardless, this is a quick, cheap and easy fix for those sensors that have already been damaged. Happy time folks!