ST Moisture Sensor Battery Replacement

(Kmugh) #1

The ST moisture sensors come with a CR2 battery that fits so snugly in the plastic housing that it is almost impossible to remove. The sensor comes with a fabric ribbon/strip to assist in removing the battery, but the end of the strip that it supposed to be firmly held by the housing rips off easily.
I finally used a screwdriver to take the battery out only to notice dents in the rechargeable (I know!) CR2 battery that I put in when I bought the sensor.

I am wondering if I can solder wires and connect the sensor to an external AA/AAA housing. Questions I have are:

  1. Whether CR2 batteries are 3V (as opposed to 3.xV - like 3.3V, etc)
  2. Whether I can replace the CR2 battery on the moisture sensor with a couple of AAs (or any other cheaper alternative)


Yes you can. There is a thread on modifying presens sensors by ST to use 2xAA. You should look into it. We modified them to fit into a project case or into a bigger 4xAA case. But you get the idea.

Go there and check it out.

(Kmugh) #3

Thanks for the link.
I tried using a CR123A battery on the moisture sensor, and it works well so far.
Did not test with 2AAs since the CR123A worked.
Only thing bothering me is that CR123A batteries are 3.7V as opposed to 3V on the CR2s …