Questions and answers FAQ

DIY electronic Hydrometer

Questions and answers FAQ

  • Do I have to tare the iSpindle with weights?
    It is indispensable to enable the iSpindle functionality! Add weights such as nuts, lead balls etc. to the bottom until the inclination is 25° from the vertical. See also example pictures in the documentation. Normally about 20g are sufficient. +/- 5° deviations are often still acceptable.

  • It doesn’t work, I don’t see anything
    The best way to find out what the iSpindle is doing as information is to read it’s log. This can be done via a serial monitor like HTerm or Arduino IDE. Connect the spindle via Micro USB, then open the Com Port with the serial monitor above and read it. Set baud rate to 115200. It brings light into the dark.

Here is a youtube howto:

  • How get to the iSpindel - the portal
    Switch it on, press the reset button 3-4 times which sets up an access point. That means you will see a new Wifi network “iSpindel” where you connect to with your computer, smartphone or tablet. Now the browser should automatically redirect you to the pagehttp:// If not, navigate there yourself. If you are now on the portal page, under Configuration you can enter your token and the wifi password that you need for your network. Then click on safe and it will send the data to Ubidots. This means that the iSpindel is not reachable in normal operation, until you manually start the portal again.

  • Why can’t I access the iSpindle in normal operation
    The critical part of the battery life time is that the iSpindle is active as short as possible and maximum time being indeep sleep! The Wemos in active operation requires more than 300x of energy, so this trick is indispensable to achieve the runtime.

  • The Micro USB port is for program updates? Correct, see Firmware Update

  • How can I calibrate the voltage display? From firmware 3.0 on you can adjust the conversion factor. By default, factor 191.8 is used. You can adjust by this formula: ```` (displayed voltage / measured voltage) * current factor (191.8) = new factor

The new factor should be between current factor more or less 20% (191.80.8 - 191.81.2). ````

  • Can I operate it in a stainless steel container? Is it possible to get through the faradic cage? To achieve a sufficient WLAN signal strength you can do the following things:

    • Break open the faradic cage. This is possible by electrically separating the lid from the pot. Can be achieved by applying a silicone sealant between the two parts.
    • Use a passive antenna. Use a shielded cable that is stripped from both ends (i. e. Lambda/4), where one side ends in the pot, exactly 3.2mm. This is transmitted passively from the inside to the outside and vice versa. A good example can be found here:
    • Install a wifi range extender next to the barrel to increase the signal level.