The unit is supplied with pH solutions Kalibriereren, 2 pen knives and a calibration screwdriver. There appears to be robust. I chose due to a very positive review for this. Only later it occurred to me that this review was written by a buyer who had only this appliance. Coincidence? Maybe.
At first I had difficulty festzusstellen which knife is what there. That's not mentioned in the instruction manual. The problem is that held in English only manual. I am of the opinion that an instruction manual must be accompanied with the distribution of a device in Germany in German.
Despite quite a decent Engtlischkenntnisse make purely in English held operating instructions is a nuisance, because simply uncertainties arise. This can be compensated by imagings - unfortunately just are not there! After I had so looked at the measuring pins exactly the pressure "PH" struck me as only on one of the pins. What the other is not clear to me is also not shown in the instruction manual. At the bottom there are two screws for calibrating that are presented with wide pH ranges. Since two pH solutions were included, it would have been a lot of goal-oriented, respectively allocate exactly the screw a solution.
For me, at any rate a Kalibnrierschraube has not responded well: It turns simply a wolf. There are already visible at slight wobbles quite different figures, the settle to laaaaaaangsam again.
After I meant to get it done so about (and solely an illustrated or detailed German manual would have been necessary), I chose the occasion of a hardware store visit for a display with tablet solution for 13, indicating the pH values in the 0.2 difference , Here a clear illustrated instructions existed. The DIY solution worked very well and was recommended to me by my neighbor. These values differed from the high-quality, calibrated equipment by 0.4 to 0.6 - depending on wobbles! I have set the perfect basis tablet display my pool.
Now I ask myself why I have spent over 100 for this device, and the benefits it has for me. I'm going to now again buy pH solutions for calibrating and try again. If this fails again, I will send this very expensive part, may raise expectations that I had me clear values expected values.
It may be that the very poor operating instructions generated such deficiencies. But I am of the opinion that an instruction manual must be prepared in German, in the alternative are imagings settle. Then it must be detailed. If the calibration process is so insufficient dasrgestellt, the nerve is made: The device can not even need to be used. It then simply no value or it is useless. I am quite accustomed etc. fend me a variety of "Chinese" operating instructions, but so it goes simply not because of the sensitive operation is shown insufficient.