spannerhead
Member
I bought an ec meter from eBay and it only reads us/cm. Can I convert this to ec or is it just a cheap shit meter and I need to get a decent one? Googled it but can't find a conversion chart.
Meter only reads us/cm and I need ec, can I convert?
- Thread starter spannerhead
- Start date
EC is measured in Siemens per meter. (S/m). Convinient unit is microseimens per centimeter (uS/cm) or milisiemens per centimeter (mS/cm). What is often refered as EC is actually mS/cm, so if you want that measurement you just divide uS unit with 1000.
TDS (ppm) is actually not a very good measurement unit as it is the estimate (wrong estimate) of the amount of diluted solids. There are three different conversion charts from EC to TDS, so you can expect much confusion when using it.
USA 1 ms/cm (EC 1.0) = 500 ppm
European 1 ms/cm (EC 1.0) = 640 ppm
Australian 1 ms/cm (EC 1.0) = 700 ppm
TDS (ppm) is actually not a very good measurement unit as it is the estimate (wrong estimate) of the amount of diluted solids. There are three different conversion charts from EC to TDS, so you can expect much confusion when using it.
USA 1 ms/cm (EC 1.0) = 500 ppm
European 1 ms/cm (EC 1.0) = 640 ppm
Australian 1 ms/cm (EC 1.0) = 700 ppm
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Sativied
Well-Known Member
Only difference between most EC and most ppm meters is that the ppm meter converts the value to ppm for the display. Check out the following reference:
http://milwaukeetesters.com/pdf/ph-ec_info.pdf
If it's a 0.5 factor, which most of those cheap chinese clones on ebay use, it's just a matter of doubling the value and removing 3 zeros. E.g 500 ppm = 1.0EC
http://milwaukeetesters.com/pdf/ph-ec_info.pdf
If it's a 0.5 factor, which most of those cheap chinese clones on ebay use, it's just a matter of doubling the value and removing 3 zeros. E.g 500 ppm = 1.0EC
waterdawg
Well-Known Member
It is my understanding that all meters, EC and TDS meters measure EC, the difference being TDS meters do the calculation re. Multiplication factor for you. Knowing the conversion factor will enable you to know both. My HM EC-3 has a conversion factor of .5 so if my display shows 1000 my tds is 500. Not sure why EC is better or worse, are they not the same thing really. But yes it can be confusing to say the least lol.
Sativied
Well-Known Member
Technically EC is more accurate because the conversion factors used are simplified, there's another factor that plays a role. Don't remember what it was, similar to temperature in ph measurement. However, most cheap meter are not THAT accurate in the first place, so the rounded result on the screen is the same.
Being in europe I was used to EC but now buy ppm meter on purpose. Just a personal preference, numbers like 400-1000 ppm work better than 0,8-2,0 etc.