ExtechInstruments RE300 ExStik ORP Meter

Accuracy and value for money

For over a month, this ORP meter performed like a champ.The other day, after submerging about 1/2 into water for a test, the meter refused to "Self Check" when turned back on. After disassembly, I found moisture in the compartment where the module plugs into the stick. Blew out, let dry a few hours and the unit returned to self check properly.Today, the unit failed to self check and, upon calling FLIR, the tech ran me through a "software reset" which did not fix the problem. I was then connected to a CSR who asked for my invoice and said that a new unit would be sent to me ASAP. The service was excellent, i received the new item in a timely mannerIt would appear that this unit is really not well enough designed for regularly swapping out the ORP module with the pH module and maintaining waterproof status. I recommend that you make sure the unit is tightly assembled upon receipt and, if you need a pH meter, to purchase a separate product. I will use this unit to only check ORP and will not submerge beyond the module locking nut.

I wanted to use the meter in demonstrating the ORP in ionized water, compared to tap water. It took too long to get to the reading of the ORP, it also did not give an accurate reading when it was in the minus range. Plus the minus range only went to - 100. Some of the ionized water samples were - 200 and more, the Extech meter could not give those readings.

This device is awesome. It is compact, accurate and reliable. It is easy to use and maintain, and provides readings relatively fast.

Purchased the RE300 from T.E.Dep. and was shipped a unit with a dry probe. Unit provided inconsistent and unreliable readings. T.E.Dep. refused to take it back (was at day 45 from purchase) so they brushed me off with the "no returns period" statement and pointed me to the manufacture to get it replaced.Contacted manufacturer and was shipped a replacement probe which turned out to be even more unreliable than the one it was replacing. The replacement unit gives readings all over the place when sampling the same solution over and over. If the probe is left in the sample, it will give a reading of 0mv after about 3 minutes.Contacted manufacturer again (Frank) and was given a "that's interesting" response when I explained the results I was getting. He forwarded me to Tech Support where I ended up in voice mail. I called right back and the lady who answered the phone made arrangements to send me another replacement.If the 2nd replacement works, I'll adjust my rating accordingly.Just received the replacement of the replacement and it too is absolutely unreliable. Soak in distilled water (or tap) for 10 minutes, turn on, swish into solution to be tested, wait 1 to 3 minutes for stable reading. Reading never stabilizes and removing the probe, turning it off and back on again and into the solution gives yet a different reading than the one just before it and it is off by over 50 Mv.The unit is made in china and I'm betting that the age of the probe having traveled that far may have a lot to do with why it doesn't work. It may be simply too old.I'm going after a refund now. I'm sick of wasting my time. When I shell out 100 bucks for a probe, I expect it to work.

They need to add more In depth instructions. My meter is reading all over the place. I’ll add hupochlorousacid and it goes down. Started displaying ph for some reason. Gremlins. Trying to problem solve or get refund.

works great

We use handheld testers to verify calibration results on production equipment. I have a full range of these Extech stiks and they work well. Calibration is normally with one standard. Provides a quick and convenient way to spot check ORP in different locations. Very rugged. Instructions are translated from Chinese, but its pretty easy to use. I recommend this range of sticks.Note that I have lots of the Extech sticks for various measurements, I am in the industrial water business, I have bought 20 or more of them as well as other brands. This one particular stick is the first one that has failed. When I received it I did not check out, the sensor is held on with a hand nut, it was not tight, my bad, got wet on the inside and $100 gone, used it once, like it, but the children on the assembly line were either not given food that day or working for 20 hours straight. Hey you probably don't want to believe it but I've been to China a lot, it is what it is.So check the assembly before you use, just in case the nut wasn't tightened properly. They don't like water on the inside.