Brewometer kickstarter thoughts - digital bluetooth hydrometer

[TorMag]

It's a hydrometer - use it like any other. Maybe I don't understand your question?

WHAT????? It's a hydrometer? Damn it, I ordered the GD wrong thing. Thanks for the help buddy.

 

[user 204491]

WHAT????? It's a hydrometer? Damn it, I ordered the GD wrong thing. Thanks for the help buddy.

Sorry, what did you think you ordered? Maybe we can help you out.

It's not a hydrometer exactly. It's a unit that you drop in your fermenter and it constantly measures both specific gravity and temperature, reporting those over bluetooth to a nearby device like a phone or tablet.

 

[TorMag]

Sorry, what did you think you ordered? Maybe we can help you out.

It's not a hydrometer exactly. It's a unit that you drop in your fermenter and it constantly measures both specific gravity and temperature, reporting those over bluetooth to a nearby device like a phone or tablet.

I thought it was a toaster! My wife is going to be pissed.

 

[user 204491]

I thought it was a toaster! My wife is going to be pissed.

Haha, yeah, there's no helping you then! You're on your own with that one

 

[Murphys_Law]

I thought it was a toaster! My wife is going to be pissed.

Well, now that you have it may I suggest you repurpose it and use it for something else? You may want to try and use it for beer making instead!

 

[TorMag]

In all seriousness. I know it is a hydrometer and I know what they do. What I meant was how to you go about using this to calculate efficiency. I've looked at the calculators, they have adjustments for the temp your hydrometer is calibrated for, is that something you have to worry about with this device? When your mash is done, do you just scoop out a pitcher of wort, let it cool down a bit and drop the device in to get a reading? At that point do you have to compensate for the temp?

 

[LBussy]

In theory, the app adjusts for temp. In practice with any hydrometer I've noticed the closer it is to calibration temp, the better the reading is regardless of how careful you are about the adjustment.

 

[user 204491]

In all seriousness. I know it is a hydrometer and I know what they do. What I meant was how to you go about using this to calculate efficiency. I've looked at the calculators, they have adjustments for the temp your hydrometer is calibrated for, is that something you have to worry about with this device? When your mash is done, do you just scoop out a pitcher of wort, let it cool down a bit and drop the device in to get a reading? At that point do you have to compensate for the temp?

So again, just to be clear, this isn't an actual hydrometer, and the accuracy of this unit (for me at least) is not sufficient for me to take my "truth" readings throughout the brewing process. For that I use a set of precision hydrometers.

As far as measuring efficiency goes, I would look to a program like Brewer's Friend (that's what I use) or Beersmith. Here you take readings throughout the brew day (post-mash, pre-boil, post-boil, end of brew day), and they will calculate the efficiency for you as you go. You can also use some of the one off calculators, but I just find the software to be easier as you're using it to look at your recipe and what not during brew day, so it's pretty easy to just plug the numbers in.

Post brew day you no longer calculate your efficiency, but you look to calculate the attenuation you're getting from your yeast (basically how much of the available sugar has been converted to alcohol). For that I also recommend using a precision hydrometer.

The Brewometers are great for looking at things like fermentation trends, knowing when to move on to the next step in your process, and so on, but with +/- 2 gravity points accuracy, that could impact your efficiency and attenuation numbers pretty severely.

 

[user 204491]

Oh, and no, you shouldn't have to worry about making temperature adjustments with these units, but keep in mind that the sensor is measuring the temp of the air inside the Brewometer, not measuring the temp of the wort directly. That means it will take a bit to adjust to matching the temp of your beer/wort. Not a big deal if you're using it just to measure gravity, but if you're using it to take a temp reading, give it a few minutes to adjust.

 

[TorMag]

Oh, and no, you shouldn't have to worry about making temperature adjustments with these units, but keep in mind that the sensor is measuring the temp of the air inside the Brewometer, not measuring the temp of the wort directly. That means it will take a bit to adjust to matching the temp of your beer/wort. Not a big deal if you're using it just to measure gravity, but if you're using it to take a temp reading, give it a few minutes to adjust.

Thanks, both those answers help a lot. I appreciate it.

 

[BrunDog]

In all seriousness. I know it is a hydrometer and I know what they do. What I meant was how to you go about using this to calculate efficiency. I've looked at the calculators, they have adjustments for the temp your hydrometer is calibrated for, is that something you have to worry about with this device? When your mash is done, do you just scoop out a pitcher of wort, let it cool down a bit and drop the device in to get a reading? At that point do you have to compensate for the temp?

No, this is not practical for this application. It's not an 'instant read' hydrometer. You should use a refractometer for this purpose. Or use a glass hydrometer and thermometer and do the temp calibration calculations.

 

[Murphys_Law]

So far the only issue I have with my brewometer is that he's lonely and needs a friend. I may have to order a 2nd one soon!

 

[user 204491]

I swear I wish I had like a dozen of these things, but for now I will make due with only two!

 

[TorMag]

No, this is not practical for this application. It's not an 'instant read' hydrometer. You should use a refractometer for this purpose. Or use a glass hydrometer and thermometer and do the temp calibration calculations.

So what you are saying, is this is not good for determining your OG and FG?

 

[Derp]

So what you are saying, is this is not good for determining your OG and FG?

Properly calibrated, it's good enough for my purposes, but I still use a refractometer to take readings pre- and post- boil. After the wort is chilled and in the fermenter I verify that the Brewometer is reading within a point or two of the final refractometer reading and then I let it do its thing. Once I see that it has settled down to my expected FG for a couple of days I consider fermentation to be finished and transfer into kegs without a final refractometer reading.

 

[Vandulus]

So what you are saying, is this is not good for determining your OG and FG?

It depends on how accurate your measurements need to be. According to their FAQ it's accurate to +/- .002 SG points which should be more than enough for most people. The only use I can see where that may not have enough accuracy is when selling beer as the ABV can only be +/- .3% off from label which .002 SG points comes awfully close to.

 

[TorMag]

It depends on how accurate your measurements need to be. According to their FAQ it's accurate to +/- .002 SG points which should be more than enough for most people. The only use I can see where that may not have enough accuracy is when selling beer as the ABV can only be +/- .3% off from label which .002 SG points comes awfully close to.

For a second there I was worried I wasted $120.00

 

[PlexVector]

I just used mine for the first time. The data only makes sense when you look at the graphed data. When you trend the data it pretty darn accurate.

 

[enkamania]

I keep averages for 8, 24, 48 and 72 hours.

 

[BrunDog]

So what you are saying, is this is not good for determining your OG and FG?

No, that's not what I said. But it seems you have received your answers from the other responses. Good luck with yours.

 

[jimmayhugh]

Got my Brewmometer yesterday.

Here's a short PHP script that will interrogate the brewmometer, and display it. I use Debian, and an odroidC2, so I'm not guaranteeing that it will work on any other system.

<?php
 
//Reduce errors
error_reporting(~E_WARNING);

$brewometer = "XX:XX:XX:XX:XX:XX"; // put your brewometer MAC address here

$command1 = "gatttool -b ".$brewometer." --char-read -a 0x3b";  // get SG
$command2 = "gatttool -b ".$brewometer." --char-read -a 0x37";  // get temp
$command3 = "gatttool -b ".$brewometer." --char-read -a 0x48";  // get battery

while(1)
{
  $result = exec ( $command1 );
  $resultArray = explode(":", $result);
  $result = hexdec(trim($resultArray[1]));
  $result = (float)(($result-19) / 1000) + (float)1.000;
  $sgStr = sprintf("SG - %01.3f", $result);
  $result = exec ( $command2 );
  $resultArray = explode(":", $result);
  $tempStr = hexdec(trim($resultArray[1]));
  $result = exec ( $command3 );
  $resultArray = explode(":", $result);
  $batStr = hexdec(trim($resultArray[1]));
  echo $sgStr."\n"."Temp - ".$tempStr." degrees\n".$batStr."% remaining\n\n";
  sleep(1);
}

?>

More to follow...

 

[boat_eggs]

anyone use rechargeable batteries in these? wondering if the higher voltage will burn up the brewometer

 

[BrunDog]

Should be a non-issue. How much higher is voltage?

 

[CaptnDelta]

anyone use rechargeable batteries in these? wondering if the higher voltage will burn up the brewometer

Which rechargeable battery has a higher cell voltage than alkaline?

Cheers,
-Th

 

[user 204491]

From their blog:

Battery (CR123A 3-volt, non-rechargeable battery). LiFePO4 rechargeable will work but are lighter and require multipoint calibration, other rechargeable will not (voltage too high).

I got the exact ones the units ship with to avoid any problems. They're $1.50/each if you buy them in 12 packs from Amazon. That's basically 50 cents per month of usage.

https://www.amazon.com/gp/product/B000IXCO8K/?tag=skimlinks_replacement-20

 

[jimmayhugh]

I got it working with my RPi3 and some coding. I save the data points to a MySQL database, and uses gnuplot:

More to come...

 

[LBussy]

Is that SG plot going backwards?

Looks good! I love how everything is hackable these days.

 

[jimmayhugh]

Is that SG plot going backwards?

Looks good! I love how everything is hackable these days.

No, actually that's just sitting in a jug of water that sitting on top of one of my computers .

I'm getting ready to move it into a spare refrigerator to see how it reacts at fermentation temps.

 

[Derp]

I got it working with my RPi3 and some coding.

That's fantastic. I don't feel very good about leaving an iPad in my garage 24/7.

 

[boat_eggs]

From their blog:

Battery (CR123A 3-volt, non-rechargeable battery). LiFePO4 rechargeable will work but are lighter and require multipoint calibration, other rechargeable will not (voltage too high).

I got the exact ones the units ship with to avoid any problems. They're $1.50/each if you buy them in 12 packs from Amazon. That's basically 50 cents per month of usage.

https://www.amazon.com/gp/product/B000IXCO8K/?tag=skimlinks_replacement-20

Thanks, I guess I missed that somehow.

BrunDog: most rechargeable Li batteries chemistries are 3.7v or higher. The cr123a batteries are 3v