Refractometer

[HPD Turbo]

I just purschase a refractometer. I allready and the diference with the Hidrometer is huge: Refractometer 1.028, Hidrometer 1.023.
Is this normal?

 

[saltysupply]

yup the difference can vary alot, especially if the hydrometer is old or dirty.

 

[Travis L. Stevens]

Did you calibrate it with a solution near what you're measuring, or just plain freshwater?

 

[Mr31415]

Stupid question - but you are using the hydrometer's tables when determining the SG? Is the refractometer ATC?

 

[HPD Turbo]

Travis:
Yes I calibrate with destilated water.

Mr31415:
Yes I am using the Hidrometer table for SG, what is ATC?

Thanks guys.

 

[Mr31415]

Automatic Temperature Compensation.

 

[HPD Turbo]

<a href=showthread.php?s=&postid=11076257#post11076257 target=_blank>Originally posted</a> by Mr31415
Automatic Temperature Compensation.

No it is not, in the intruccion saids that it has to wait 30 seconds for temp to equal the instrument.
Thanks for your inputs.

 

[ScottL4619]

I think that means that it is ATC; my ATC refractometer says the same thing. You have to wait 30 seconds so that the temperature of the water matches the temperature of the prism. If they are the same temp, then the refractometer will be accurate.

 

[HPD Turbo]

Yes you are right, it is ATC.
I am still shock on the readings. As I know now my water was about 1.031 SG last month (1.026 Hidrometer reading).

Thanks a lot!!

 

[Randy1]

You mean we should wait 30 sec. after putting the drop of water on the refractometer before reading??

 

[ScottL4619]

I generally put some water on, flip the flap down, and then wait a little bit. I don't really time it out, I usually just go and do something for a minute and come back and check it. As long as the water stays put, you could probably leave it on there for hours and it would still be accurate. Just make sure it's at least 20 or 30 seconds before reading. This allows the water temp to match the temp of the device and makes it more accurate.

 

[skeeter_ca]

I did not know that!