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.
Brewometer kickstarter thoughts - digital bluetooth hydrometer
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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
Well-Known Member
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!
I swear I wish I had like a dozen of these things, but for now I will make due with only two!
So what you are saying, is this is not good for determining your OG and FG?
Derp
Well-Known Member
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.
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
Mellow Goose Brewing
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.
I keep averages for 8, 24, 48 and 72 hours.
No, that's not what I said. But it seems you have received your answers from the other responses. Good luck with yours.
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.
More to follow...
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.
Code:
<?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...
OP
OP
boat_eggs
Well-Known Member
anyone use rechargeable batteries in these? wondering if the higher voltage will burn up the brewometer
Should be a non-issue. How much higher is voltage?
CaptnDelta
Well-Known Member
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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
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
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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...
More to come...
Is that SG plot going backwards?
Looks good! I love how everything is hackable these days.
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
Well-Known Member
That's fantastic. I don't feel very good about leaving an iPad in my garage 24/7.
OP
OP
boat_eggs
Well-Known Member
Thanks, I guess I missed that somehow.
BrunDog: most rechargeable Li batteries chemistries are 3.7v or higher. The cr123a batteries are 3v
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The Bean micro board can handle 3.6V, so yes, technically 3.7 is too much. The weight difference is another deal breaker. So no rechargeables!
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.
Things settled out nicely in the Fermentation Chamber (it's still just a jug of tap water):
HLSheppard
Well-Known Member
I think my Brewometer / Tilt's battery is dying as it floats in my latest IIIPA. Not only has the range drastically decreased, but the readings are bouncing wildly. 1.041 to 1.034, then 1.011 to 1.024 in the space of two days.
Amazon is selling there 7" Android Fire tablets for $33 today on Prime Day. Not a bad price for a dedicated tablet
https://www.amazon.com/gp/product/B00TSUGXKE/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B00TSUGXKE/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
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I gave up using the Fire tablet because Amazon would download/update every evening which causes the Fire to lose wifi connection. When it reboots it wouldn't auto connect to the app. There may be a work around out there but I just bought a used cellphone to use instead.
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Things settled out nicely in the Fermentation Chamber (it's still just a jug of tap water):
But shouldn't it always be reading ~1.000? Something else going on in that graph?
I have been using my brewometer for about 3 months (battery still going ok).
It's pretty useful tool, and quite precise if you avoid it getting stuck in a krausen or next to the carboy wall.
Here's my Magic Hat #9 clone:
That's what I assumed as well, but the graph showed a different situation.
The jug was originally filled with tap water, and the Brewometer dropped in there. As it sat at room temperature, I noticed a gradual rise in SG. I decided to place it on one of my computers, figuring that the computer would warm the water up, which it did. It also caused a rise in the SG as the water warmed up. I then took the whole shebang to my Fermentation chamber and let it cool down. As it did, the SG also came down.
My software gets the raw data from the Brewometer and displays it with little modification. The temperature is simply converted from a hex value to a decimal value, while the SG reading undergoes a straight forward calculation. I posted a version of the calculation here. The actual calculation is:
Code:
$result = (float)(($result-19) / 1000) + (float)1.000;I'm not privy to the inner workings of the Brewometer, so I don't know if there's a temperature compensation algorithm in their software, but I'm going to continue looking around.
If I understand, you can jailbreak it and basically turn it into just an android tablet
I agree, there must be something like that going on under the hood of their kit, because at the very least, SG should drop with a rise in temperature, yes?
Cheers!
That's been my understanding...
From their FAQ:
Q. Does the SG reported by the Tilt/Brewmometer compensate for the current temperature automatically?
A. Due to the polycarbonate housing of the the Tilt/Brewometer, no correction is needed for 38F to 98F. Temperatures above 98F result in an decrease of SG of about 1 point per 10F. i.e. water at around 160F will read 0.994.
That's what I assumed as well, but the graph showed a different situation.
The jug was originally filled with tap water, and the Brewometer dropped in there. As it sat at room temperature, I noticed a gradual rise in SG. I decided to place it on one of my computers, figuring that the computer would warm the water up, which it did. It also caused a rise in the SG as the water warmed up. I then took the whole shebang to my Fermentation chamber and let it cool down. As it did, the SG also came down.
My software gets the raw data from the Brewometer and displays it with little modification. The temperature is simply converted from a hex value to a decimal value, while the SG reading undergoes a straight forward calculation. I posted a version of the calculation here. The actual calculation is:
Code:$result = (float)(($result-19) / 1000) + (float)1.000;
I'm not privy to the inner workings of the Brewometer, so I don't know if there's a temperature compensation algorithm in their software, but I'm going to continue looking around.
I did some quick number crunching, assuming a hydrometer calibrated at 60F, measuring only water, the gravity readings from the brewometer from 38F to 98F should range from 1.001 to 0.994.
I tried to back into a temperature that would give me a reading of ~1.018 like your graph showed, but with the gravity of water at 32F being only 1.0008 I don't see that being feasible. And as you said it was warmer, not cooler, so the gravity should have read lower.
Huh?
You asked, "SG should drop with a rise in temperature, yes," and according to the manufacturer the answer is no.
They state that temperature does not impact gravity readings in the same way they do hydrometer readings, as they are not measuring the gravity in the same way that an actual hydrometer does.
But in The Real World, the SG does in fact change with temperature
And that's not something "wrong" with hydrometers.
Fluid volume really does change with temperature, thus changing the SG.
I would expect a "digital hydrometer" to respect physics...
Cheers!
And that's not something "wrong" with hydrometers.
Fluid volume really does change with temperature, thus changing the SG.
I would expect a "digital hydrometer" to respect physics...
Cheers!
But in The Real World, the SG does in fact change with temperature
And that's not something "wrong" with hydrometers.
Fluid volume really does change with temperature, thus changing the SG.
I would expect a "digital hydrometer" to respect physics...
Cheers!
Between 4C (about 40F) and 30C (about 90F) the density of water drops only by about half a percent. Or from 1.000 to 0.995. It's a subtle effect and a few degree change during fermentation won't change gravity much at all.
nope. They measure the fluid density the same way hydrometer does using method that goes back to Archimedes.
All of the "number crunching" and hypotheticals doesn't invalidate the real-word results. Just for grits and shins, I'm gradually lowering the temp of the water jug to 38 degrees today and will continue to monitor and post the results.
What's with the quotation marks? That sort of comes of as dismissively condescending. You know we're right, right?
My "number crunching" clearly shows that your real-world results are invalid and that your initial hypothesis that the issue was simply temperature related can't be the whole story. The error you showed can't be dismissed that easily. There is something wrong with either your code, your brewometer, or your physical setup. Despite what your electronics say, I promise that your jug of plain water was in fact not at a specific gravity of 1.020 @ 90F. We're trying to help you, man...
I'm assuming the brewometer uses a gyroscope to detect the level of tilt? My guess, based solely on the one graph, is that the readings reported by the gyroscope are some how temperature dependent. It's a wild guess as I have yet to play with a gyroscope in my projects, but notice that the inaccuracy only occurs way above normal fermentation temperatures, being a new product maybe the developers didn't do much testing in this temperature range, or think it was necessary? I don't know...
My questions are is error repeatable? Does it have a lower temperature limit? Is this just your unit, or is this every unit? What is actually the accurate working temperature range of these meters?
