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Electrical conductivity for soil by milliVolts

May 18, 2009

Hi,
we are trying to measure electrical conductivity for a soil but we did not have a electrical conductivity meter instead we used a pH meter that measure electrical voltage by mV (millivoltmeter), my question is how to convert this reading which was -4 mV in to MS-1,
I am grateful for your time to answer thanks.
Sydney/Australia

Nawal Mohidin
student - Sydney, NSW, Australia

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Hi, Nawal. I don't believe that you can measure conductivity with a pH meter. Neutral water with just a little salt and low conductivity will read pH 7.0; neutral water with a lot of salt and high conductivity will read pH 7.0.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
May 18, 2009

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Lab grade pH meters have a setting that reads in m volts. After all, a pH meter is nothing but an extremely sensitive volt meter with some unusual probes. Ted's answer is still correct. You can not convert volts to conductivity without a lot of conditions and special equipment. James Watts - Navarre, Florida May 19, 2009 May 20, 2009 VOM meter on Amazon (affil links) Hi Nawal, A multimeter suitable for your readings costs only a few dollars from your closest Dick Smith or Jaycar store. You can read resistance and take the reciprocal to get conductivity, or for a few more dollars you can get one with a direct conductivity scale. (For people outside Australia: Dick Smith and Jaycar are chains of electronics sellers). Bill Reynolds [deceased] consultant metallurgist - Ballarat, Victoria, Australia We sadly relate the news that Bill passed away on Jan. 29, 2010.

I think that for soil testing he is going to have to have probes of a very specific area. Also, for soil, he is going to have to supply a specific moisture content or the numbers mean absolutely nothing.

James Watts
- Navarre, Florida
May 21, 2009

I had millivolts readings of hanna pH meter model 611 which surprisingly gave a similar figure with a conductivity meter reading in microsiemens but divided by a factor of 10.does this mean that millivolts have direct relation to conductivity?

simon mukono
consumer - kenya
July 16, 2009