View single post by kingbob151
 Posted: Tue Nov 30th, 2010 03:45 pm
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kingbob151

 

Joined: Wed Oct 13th, 2010
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I had the cust contact the local water board. Here is an excerpt from the email he sent me.

1.  Conductivity.  Moisture sensors do just that:  measure the dryness or moisture content of the items being dried.  The conductivity of water provides the path of this measurement between the two source points provided by the sensor.   Here the degree of resistance (or conductance) is read by the sensors, which eventually provides an interpretation to the degree of dryness.  This conductance within water is measured in millimhos per centimeter.  The national average of public tap water conductance is generally above 600 mmhos/cm.  Here, in Monterey Park, it is 750 mmhos/cm. 

I pulled up the latest specifications of the Foresthill water provided by the Foresthill Public Utility District.  The reading astounded me.  We have the public tap water at only 30 mmhos/cm.  That means that our Foresthill water has extremely low calcium and mineral content thus it "could" cause the sensor to read erroneously the amount of water within the source, i.e. clothes.  This could be the reason that the moisture sensor is not working right - it's input source (clothes) has the wrong conductance (water) to which it was designed.  But this wrong conductance cannot be changed since this is our extremely wonderful water being used.  This is a design issue, I believe.  What do we do now?  How do we adjust for different levels of mmhos/cm?  It is an ohms law problem.