Broken Refractometer?

[zman]

I have a REF103 refractometer that does not seem to want to zero out. I calibrated it using some distilled water. When I adjust the calibration screw the line is at the bottom of the zero and not at the actual zero line If I screw in the screw the light dark field gets lower. If I turn the screw out it does not go above the bottom of the "0". The instructions say to adjust the screw to make the light dark boundary coincide with the null line. What exactly is the "null line"?


Thanks,

 

[zman]

24 views and not one reply? Doesn't any one here use A refractometer?

 

[Shooter]

I have a REF103 refractometer that does not seem to want to zero out. I calibrated it using some distilled water. When I adjust the calibration screw the line is at the bottom of the zero and not at the actual zero line If I screw in the screw the light dark field gets lower. If I turn the screw out it does not go above the bottom of the "0". The instructions say to adjust the screw to make the light dark boundary coincide with the null line. What exactly is the "null line"?


Thanks,

The "null line" is the zero line. Are you adjusting the actual set screw and not the locking nut?

 

[zman]

Thanks for the reply

Yep. I am adjusting the adjusting the set screw and I figured that the "0" line was the null line and not the bottom of the actual number, but I wanted to make sure. I can screw the set screw until it is almost out of the refractometer. The locking nut does not seen to turn at all. I contacted the place where it was purchased and it is still under warranty

 

[Homercidal]

I never had that problem. I was bummed to find that my refractometer was way off after I had calibrated it the Last batch though. Then I realized that I had calibrated it when it was much colder in the house!

 

[Shooter]

Thanks for the reply

Yep. I am adjusting the adjusting the set screw and I figured that the "0" line was the null line and not the bottom of the actual number, but I wanted to make sure. I can screw the set screw until it is almost out of the refractometer. The locking nut does not seen to turn at all. I contacted the place where it was purchased and it is still under warranty

Well, I'd probably just take into them and see if they have any advice. If not, sounds like a new one won't be a problem. Good luck!

I never had that problem. I was bummed to find that my refractometer was way off after I had calibrated it the Last batch though. Then I realized that I had calibrated it when it was much colder in the house!

I went a long time without ever needing to calibrate mine. Recent swings in temperature have made it necessary to calibrate before every brew session.

 

[bad coffee]

Don't you guys have ATC refractos?

B

 

[Shooter]

Don't you guys have ATC refractos?

B

Yes, but they still need to be calibrated. ATC doesn't mean calibrate it once and done. Otherwise they could just do that at the factory and there wouldn't be any need for a calibration screw.

 

[Homercidal]

The refractometer needs to be calibrated to the surrounding air temp (The thing will read differently depending on how cold the unit is) But you don't have to calibrate it to the temperature of the sample.

 

[Shooter]

The refractometer needs to be calibrated to the surrounding air temp (The thing will read differently depending on how cold the unit is) But you don't have to calibrate it to the temperature of the sample.

Exactly!

 

[a10t2]

The refractometer needs to be calibrated to the surrounding air temp (The thing will read differently depending on how cold the unit is) But you don't have to calibrate it to the temperature of the sample.

I think this needs to be clarified a little. As long as there's an ATC function and the refractometer body is within the effective range (50-86°F generally), the refractometer won't need to be re-calibrated.

The way ATC works is by mounting the reticle on a bimetal strip, like a thermostat. The range of motion is still limited, which is why it only works within a certain temperature range, but as long as you calibrate it at the correct temperature it will be accurate throughout the entire range. If you need to read it outside that range, then yes, you would have to re-calibrate.

 

[Homercidal]

I think this needs to be clarified a little. As long as there's an ATC function and the refractometer body is within the effective range (50-86°F generally), the refractometer won't need to be re-calibrated.

The way ATC works is by mounting the reticle on a bimetal strip, like a thermostat. The range of motion is still limited, which is why it only works within a certain temperature range, but as long as you calibrate it at the correct temperature it will be accurate throughout the entire range. If you need to read it outside that range, then yes, you would have to re-calibrate.

I have not used mine much, but my limited experience shows that there is some discrepancy between temps that far apart.

At any rate, it's super easy to calibrate, as compared to pulling a large sample and cooling it and floating a hydrometer in it. If I have to check it each time, I'm not going to sweat it. And I'd rather check it each time than find out later that it was off by 10 points.

 

[zman]

Gotta give BIG Props to Williams Brewing. They got the defective refractometer on Wednesday and got the replacement yesterday.

 

[Bigscience]

The refractometer needs to be calibrated to the surrounding air temp (The thing will read differently depending on how cold the unit is) But you don't have to calibrate it to the temperature of the sample.

I'll recalibrate mine a few times during the brew day as the temp really changes in the garage with the burners fired up. It doesn't usually require too much adjustment but it also only takes a few seconds to check. I do verifications when checking fermentations and since the temp is pretty constant, it's always right on.

 

[bad coffee]

The refractometer needs to be calibrated to the surrounding air temp (The thing will read differently depending on how cold the unit is) But you don't have to calibrate it to the temperature of the sample.

hmm. I didn't know that. I'll have to try calibrating it next brew day. I've wondered about my readings seeming to be a bit off after the boil. (when the kitchen is hotter...)

B