In recent years there have been significant changes to the availability of home brewing equipment, mostly due to the ubiquitous deployment of Craft Breweries throughout North America and Europe. The trickle down effect means the average home brewer has progressed beyond the plastic bucket and has a few more high tech arrows in their quiver. The device that has caught our attention is a digital hydrometer designed for home brewers and produced by a company from the Netherlands called Brewbrain. The device is 'The Float'.
Float hydrometer and thermometer
The idea of placing a device that lives in-situ while your wort is fermenting to measure specific gravity and temperature has been around for awhile. The over-riding advantages are: less chance of introducing wort infection as a consequence of drawing samples for external measurement; and preservation of volume. It also allows for obtaining readings during spunding without having to exercise parasitic draw down of the fermentation vessel. The current enabling technologies these devices use are Wifi, Bluetooth, Li_ion cells, and miniature gyro sensors.
We were attracted to the form factor of the 'Float' design from Brewbrain for a couple of simple reasons. Our reasoning was:
1: the use of Li-Ion 18650 rechargeable cells give a higher density and more precise and consistent center of gravity than devices that may use smaller or non-rechargeable cells, and this should result in less variability in SG readings that are so easily affected by interference in the wort caused by metabolic turbulence, and subsequent adhesion of hop detritus to the hydrometer case.
2: Keeping it simple: the use of Wifi instead of bluetooth
a: Most home internet ecosystems already have Wifi running persistently. Both Bluetooth and Wifi devices use the 2.4 GHz band, so they have the potential to conflict. Although BT's technology of adaptive frequency hopping was designed to reduce interference between technologies that share the 2.4 GHz spectrum, what if your BT device hops onto the same frequency your Wifi is broadcasting? If this happened when a digital hydrometer is trying to send the readings to your log file via BT, the result could be packet collisions resulting in corrupt data.
b: If a digital hydrometer is using bluetooth to transmit data, and you want to collect that data in a log file, then you need to always have a device (tablet, smart phone, etc.) that is running the hydrometer software in real time open, and is capable of receiving bluetooth signals near your fermenter. In turn, if you want to transmit that data to a cloud based log file, then that device is also Internet connected. This means the extra burden and cost of having a dedicated device you can leave near your fermenter at all times, and probably having it plugged in. For battery only powered devices, this is not an advisable charging algorithm. For a Wifi enabled digital hydrometer, you connect it with the existing Wifi router that is already on your network, and this facilitates the direct transmission of your data from the hydrometer to your cloud based log file. For most users, this setup will result in significant overall cost savings to their Home Brewing infrastructure..