Jaz
Well-Known Member
I scored one of these you-beaut (you-shite) jobbies from eBay for under $20 (AUD). The video below had me intrigued; I thought since they can be calibrated, they may be a decent meter.
This unit has a Vivosun stamp on it but the buttons don't perform the same as in the video.
My guess is these units are like those Hebe vapes where every man and his Snoop Dogg pay a Chinese company to stick their logo on it and then on-sell it for twice or three times the price as the unbranded ones.
These blue ones go by various other names from what I've seen on y/t.
There's also unbranded white EC meters on eBay from under $10 which look identical bar the colour, the same button arrangement and I think the only difference between the higher priced ones is the carry case, which probably cost as much as the unit itself to manufacture, lol.
Don't ask me why there's a window in the case, you can't exactly dip the thing in solution while in the case so there's no need for a window to see the reading on the screen.
I've seen vids of people reviewing these meters for their hydro setups, straight out of the box with no hint of calibration; they don't have a clue!
Review:
First test, placing it in no-name distilled water:
A shake dry and then into Analytical Reagent, it was climbing and took quite a few minutes to settle @ 1200 μS/cm, not exactly accurate (I took a photo to save for the supplier should I need it).
Unlike the video, it took a bit of jiggery-pokery to figure out how to calibrate this one. The numbers (and letters) flash after you hold the Mode/Cal button in EC mode and instead of the up/down arrows, I was able to increase the reading using the on/off button instead but not in single digit increments like the vid; it jumps @20-30 or so with each press and it goes lower by pressing the Hold button and at the same @20-30 rate so I didn't get it exact but I was able to get very close.
I have to be honest, once calibrated this thing is surprisingly accurate, hitting the same numerical value each time I took it out and put it back into the solution over quite some time.
The downside:
I measured my tap water and after a clean I measured the solution again; it read @ 1500 μS/cm - this particular unit is not worthy of my stamp of Quality Assurance.
I took a photo and sent it with the first pic to the supplier letting him know his product isn't consistent, expecting to 'Return to Sender' his package for a replacement/refund.
His reply:
To avoid further inconvenience, we will refund you full money and you don't need to return it. Is that ok?
I can accept that, so I guess this is now my EC meter, though I'll probably end up using the battery to power my calculator.
I suspect the supplier is a distributor selling various Chinese products and has no idea about EC meters, no offer of replacement, just refund the customer, keep the feedback positive to keep selling more to unsuspecting buyers.
Conclusion:
If you have a thing for Measurements and Instrumentation, accuracy and precision or taking regular measurements for your hydroponic system and require accuracy - I do not recommend it.
I may've got a dud unit but my gut tells me all the variants will be pretty much the same; you get what you pay for.
If you're doing the odd measurement you could absolutely use this for 'relative' measurements.
i.e. it'll be able to tell if your run-off is higher or lower than what you're putting in.
As you can see, it can tell you no-name distilled water is near 0, my tap water reads about 200 μS/cm +/- 50 μS/cm depending on temp and the reagent varies between 1200 and 1500 depending on temp and how it feels at the time, lol.
Before I put it in the bin, lol, I'd put this in the Low Accuracy/High Precision category and once calibrated it was both Accurate and Precise but for who knows how long and whether it's consistent in other fluids. That wild 1500 μS/cm reading doesn't give me confidence in this unit.
I did recalibrate again and it's reading accurately so if you're prepared to calibrate regularly you may find it useful.
The following day after placing it in the solution it was still reading in the ballpark, a day later and the result was varying throughout the day, up to 150 μS/cm off the reagent scale.
Apparently the older versions had a calibration screw under the fascia sticker but the newer models have the calibration built into the programming.
This unit is calibrated to the 500ppm NaCl standard a.k.a. TDS - total dissolved solids where ppm = EC x 500
For those that don't know, different ppm standards are used, ppm500 tends to be common but some articles/books/manufacturers/nutrient suppliers use the 700ppm KCl standard, so keep that in mind if you're following ppm recommendations or better still start using EC instead of ppm as EC is a worldwide standard that doesn't change across continents, etc.
Keen to read reviews of other models from other members here.
j
This unit has a Vivosun stamp on it but the buttons don't perform the same as in the video.
My guess is these units are like those Hebe vapes where every man and his Snoop Dogg pay a Chinese company to stick their logo on it and then on-sell it for twice or three times the price as the unbranded ones.
These blue ones go by various other names from what I've seen on y/t.
There's also unbranded white EC meters on eBay from under $10 which look identical bar the colour, the same button arrangement and I think the only difference between the higher priced ones is the carry case, which probably cost as much as the unit itself to manufacture, lol.
Don't ask me why there's a window in the case, you can't exactly dip the thing in solution while in the case so there's no need for a window to see the reading on the screen.
I've seen vids of people reviewing these meters for their hydro setups, straight out of the box with no hint of calibration; they don't have a clue!
Review:
First test, placing it in no-name distilled water:
A shake dry and then into Analytical Reagent, it was climbing and took quite a few minutes to settle @ 1200 μS/cm, not exactly accurate (I took a photo to save for the supplier should I need it).
Unlike the video, it took a bit of jiggery-pokery to figure out how to calibrate this one. The numbers (and letters) flash after you hold the Mode/Cal button in EC mode and instead of the up/down arrows, I was able to increase the reading using the on/off button instead but not in single digit increments like the vid; it jumps @20-30 or so with each press and it goes lower by pressing the Hold button and at the same @20-30 rate so I didn't get it exact but I was able to get very close.
I have to be honest, once calibrated this thing is surprisingly accurate, hitting the same numerical value each time I took it out and put it back into the solution over quite some time.
The downside:
I measured my tap water and after a clean I measured the solution again; it read @ 1500 μS/cm - this particular unit is not worthy of my stamp of Quality Assurance.
I took a photo and sent it with the first pic to the supplier letting him know his product isn't consistent, expecting to 'Return to Sender' his package for a replacement/refund.
His reply:
To avoid further inconvenience, we will refund you full money and you don't need to return it. Is that ok?
I can accept that, so I guess this is now my EC meter, though I'll probably end up using the battery to power my calculator.
I suspect the supplier is a distributor selling various Chinese products and has no idea about EC meters, no offer of replacement, just refund the customer, keep the feedback positive to keep selling more to unsuspecting buyers.
Conclusion:
If you have a thing for Measurements and Instrumentation, accuracy and precision or taking regular measurements for your hydroponic system and require accuracy - I do not recommend it.
I may've got a dud unit but my gut tells me all the variants will be pretty much the same; you get what you pay for.
If you're doing the odd measurement you could absolutely use this for 'relative' measurements.
i.e. it'll be able to tell if your run-off is higher or lower than what you're putting in.
As you can see, it can tell you no-name distilled water is near 0, my tap water reads about 200 μS/cm +/- 50 μS/cm depending on temp and the reagent varies between 1200 and 1500 depending on temp and how it feels at the time, lol.
Before I put it in the bin, lol, I'd put this in the Low Accuracy/High Precision category and once calibrated it was both Accurate and Precise but for who knows how long and whether it's consistent in other fluids. That wild 1500 μS/cm reading doesn't give me confidence in this unit.
I did recalibrate again and it's reading accurately so if you're prepared to calibrate regularly you may find it useful.
The following day after placing it in the solution it was still reading in the ballpark, a day later and the result was varying throughout the day, up to 150 μS/cm off the reagent scale.
Apparently the older versions had a calibration screw under the fascia sticker but the newer models have the calibration built into the programming.
This unit is calibrated to the 500ppm NaCl standard a.k.a. TDS - total dissolved solids where ppm = EC x 500
For those that don't know, different ppm standards are used, ppm500 tends to be common but some articles/books/manufacturers/nutrient suppliers use the 700ppm KCl standard, so keep that in mind if you're following ppm recommendations or better still start using EC instead of ppm as EC is a worldwide standard that doesn't change across continents, etc.
Keen to read reviews of other models from other members here.
j
