Hey guys i have a question about my PPM/EC tester. it has two sides to it one being a EC x 500 and one being a EC x 700....im not totally sure which one i should be using or what the difference is in either. Any thoughts? thanks.

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Hey sweetie. I haven't a clue. ISO would know, as well as toke. Just thought I would drop by to say HI!!!!!! how hi? not sure.....How high are you? I am about 5'4" ...... LOL!

N0 help whatsoever. but Hello Iceice!!!

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usually to find the EC one would divide their ppm by 500(as a general unit, some meters come with conversion charts.) I'm not sure why a meter is telling you to use both calculation types. I'd say use the 500, if it has a switch or something you can switch it to the 700, but you'd need to divide your ppm by 700 instead of 500.

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Having never done hydro, I won't be any help to you, here. But, I have a related question for any electronics minded folks. If an EC meter measures electrical conductivity, wouldn't a simple ohm meter do the same? Maybe have to probes mounted on something to keep them a standard distance apart, and connect the leads of the meter to the top of the probes? Then, if one were to compare the readings of an EC meter with the ohm meter at various levels of nutes, work out a formula and use the CHEAP ohm meter, instead. Just a thought.

I would try it, if I had an EC meter. I have countless multi-meters.

Pappy

I find the multi meters to be a waste of money considering that sometimes they are even twice as expensive than if you'd bought the meters separate. Alsio, what happens when a meter or probe breaks? it may be a hassle, but having separate meters is (IMO) the easiest and most cost efficient.

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I grow my bounty and spread it to those who need it. Johny law Won't stop my crop.

The multi-meters I'm referring to, are volt/ohm meters, used for electrical troubleshooting and repair. Not a ppm/ec/tds meter. The meter would just measure the resistance (hence, the electrical conductivity) of a given solution.

My theory: The higher the solution's resistance, the lower the EC. In other words, the lower the mineral content of a solution, the higher the resistance (ohm).

Pappy

that would work, unless you were using a nutrient that caused resistance. I'm no electrician, but as far as I know silica is one such nutrient, and I use it in my hydro setups. Your theory would work for base nutrients, but as you start to add additives you might get some inaccurate readings.

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That is all an EC meter does. It measures electrical conductivity, which IS resistance to current flow. An EC meter cannot differentiate between substances in the solution.

A volt/ohm meter at Wal Mart can be purchased for less than $10.

Pappy

Pappy,

While the EC meter gives you a figure based on the electrical resistance of the fluid, the meter is also processing that figure through some algorithm to arrive at the number it gives you. Find that algorithm and you have a low-cost EC meter...likely not waterproof though...

Also, ya gotta wonder how acurate a $10 WallyWorld ohm meter is...factory calibration is not likely too good.

ISO

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Thanks for the imput guys...i have been using the 500 side of the meter and everything has been fine so i will stick with that.

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HI Jangel! lol thanks for droppin by! and dont feel too bad, im only 5'7"!

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.: Let it grow, let it grow, let it grow :.GP 4 Life