HM Digital DM-1 in-Line Dual TDS Monitor, 0-9990 ppm Range, +/- 2% Readout Accuracy

So easy to install, accurate and well made

This is a compact in-line TDS meter with two sensors. This enables a reading to be taken from two positions in an RO system. In my case I prefer to take a reading immediately post-RO membrane and a second reading post DI, the final permeate. The reading from either sensor is selected by a button for each sensor. I have checked the accuracy using measurements taken by a professional grade WTW conductivity meter and I can say that this HM device is accurate enough. Installation is straightforward. The two requisite T pieces are provided. Note that the sensors are not designed to be read water in a receptacle and will not display an accurate reading. The device is intended to be used in-line within the tubing of a live RO system. Also note that inserting the sensors into the upright of the T piece does require some force, they will not simply push in easily like a length of RO tubing. The resistance must be overcome for a correct installation. It is best practice to install the sensors into each T piece before installing the T piece. This allows you to squint through the open end of the fitting and ensure that the two sensor prongs are clearly visible and facing you as a pair and are both visible poking down into the fitting, like a pair of posts. Otherwise the device will not read accurately.

Smaller then I expected but absolutely perfect little TDs reader. Also have a handheld one and the readers are the same. Comes with battery's ready to install straight away. I am a window cleaner and will be installing this after my RO system and after my DI vessel to I can keep a clearer eye on the TDs levels.

I bought this to replace a similar device which had failed. This one outperforms the other in every way. I already have one of these which has been in use for several years alongside to one which failed and I have only just had to replace the batteries although, to be fair, it doesn't get a great deal of use. The batteries are LR44/G13/SR44W which I bought some time ago for something else but cost less than £5 for 100 from Ebay. There are no clibration adjustments so it is possibly not as accurate as some but more than adequate for most uses and with only simple on/off and in/out controls it just sits there and does the job.

Its a very good device with nice, clear instructions in English. I have mine checking the water coming from the membrane and after the di resin chamber so I can check the performance of each component. Comes with batteries already installed but annoyingly it doesnt come with any of the little blue connector clips.

Once installed which is so easy a 2 year old could do it, you just have to press the button to turn it on and look at the screen, no messing about like the hand held TDs metre. Great peace of kit at a great price.

Great product, easy to fit, comes with Velcro strips attached to make easy attachment and viewing. Auto switch off means the battery doesn’t get run down if you forget to switch it off.

Excellent and extremely useful bit of kit. I always forgot to check the levels of TDS with my manual meter when producing RODI water but now its just a press of a button! Would recommend if you have a memory like mine!!

洗車用純水器のお手軽数値測定のため導入。すでに純水器2台連結で運用してるのでそれぞれの出口に設置。 そのままでは装着できないのでホームセンターで砲金オネジチーズ、takagiのG1/2メスコネクター、ネジ付き蛇口ニップルを２個ずつ購入。amazonの一緒に購入されてる商品からクイックコネクターも準備。 別途準備したものの方が金額倍くらいかかりました(汗 苦労したかいもあり無事装着でき測定できてます。他レビューから防水ではないみたいなのでモニターの設置場所は検討中です。

Fácil instalar, confiable, me ayuda a ver como esta mi sistema

Works well

المنتج سئ ويعطي قراءه غير صحيحه جربته ووضعت مياه في كوب وسجلت قراءه المدخل والمخرج وجدت القراءه مختلفه في نفس الكوب بفرق من 5 ٪ الي10٪ درجه كما انه غالي جدا وهناك منتجات اقل سعر واعلي كفاءه وجوده

Es sencillo de usar. La cslidad parece buena. No necesita regulación