Milwaukee Digital Refractometer Off

Leafer · 01/05/2014, 05:52 PM

I believe my Milwaukee Digital Refractometer’s readings are off and I’m not sure how to correct it. I have tried calibrating with RoDI and distilled water and have changed the battery. I have a 35ppt (1.0265) standard solution that reads at 32ppt.

I’ve been mixing fresh water a little too strong because of lower than actual readings I believe. A month or two ago AWT reported my salinity at 1.028.

I have an old squinty eyed refractometer but it as corroded to the point of being unusable.

So, do buy another squinty eyed refractometer? I’d really like the Milwaukee unit to provide readings I can have confidence in.

Any trouble shooting or corrective suggestions?

Khemul · 01/05/2014, 06:19 PM

Calibrate it with the 35ppt solution.

mark54321 · 01/05/2014, 06:28 PM

I had the same problem on mine that was delivered new. Most likely the prizm was displaced. It will happen if the unit was dropped or hit hard. I got a replacement and new one is reading correctly. Did you drop yours maybe? It says in the manual to be careful with it.

Leafer · 01/05/2014, 06:29 PM

Thanks for the reply Khemul. I would love to do exactly that. However, on this digital device, I don't see any other way to calibrate then at zero unlike the look through refractometers.

Leafer · 01/05/2014, 06:36 PM

mark, thanks. I can't remember dropping mine but its possible I could have done something to displace the prizm. I've had water splashed on it and I Know its not completely waterproof. I will call tomorrow and see about possible servicing.

mark54321 · 01/05/2014, 06:38 PM

It is not possible to calibrate this unit to 35 ppm solution, you can check against it but not calibrate.

Cloudburst2000 · 01/05/2014, 09:20 PM

I have the same unit. I have 35ppt calibration solution. I calibrate the digital refractometer with the RODI water, and then I use the 35ppt solution to verify calibration. Sometimes, it is right on the money. Occasionally it is .01 off. When it is off, I just either subtract or add the difference to the water I test with the digital refractometer. I don't use the 35ppt as a calibration solution but as a reference.

01/05/2014, 05:52 PM	#1
Leafer Registered Member Join Date: Mar 2007 Location: Flanders, NJ Posts: 259	Milwaukee Digital Refractometer Off I believe my Milwaukee Digital Refractometer’s readings are off and I’m not sure how to correct it. I have tried calibrating with RoDI and distilled water and have changed the battery. I have a 35ppt (1.0265) standard solution that reads at 32ppt. I’ve been mixing fresh water a little too strong because of lower than actual readings I believe. A month or two ago AWT reported my salinity at 1.028. I have an old squinty eyed refractometer but it as corroded to the point of being unusable. So, do buy another squinty eyed refractometer? I’d really like the Milwaukee unit to provide readings I can have confidence in. Any trouble shooting or corrective suggestions?

01/05/2014, 06:28 PM	#3
mark54321 Registered Member Join Date: Mar 2009 Location: chicago Posts: 2,040	I had the same problem on mine that was delivered new. Most likely the prizm was displaced. It will happen if the unit was dropped or hit hard. I got a replacement and new one is reading correctly. Did you drop yours maybe? It says in the manual to be careful with it. __________________ ############## ______MARK_______ ##############

01/05/2014, 06:38 PM	#6
mark54321 Registered Member Join Date: Mar 2009 Location: chicago Posts: 2,040	It is not possible to calibrate this unit to 35 ppm solution, you can check against it but not calibrate. __________________ ############## ______MARK_______ ##############

01/05/2014, 06:19 PM	#2
Khemul Registered Member Join Date: Aug 2011 Location: Fort Lauderdale, FL Posts: 988	Calibrate it with the 35ppt solution.

01/05/2014, 06:29 PM	#4
Leafer Registered Member Join Date: Mar 2007 Location: Flanders, NJ Posts: 259	Thanks for the reply Khemul. I would love to do exactly that. However, on this digital device, I don't see any other way to calibrate then at zero unlike the look through refractometers.

01/05/2014, 06:36 PM	#5
Leafer Registered Member Join Date: Mar 2007 Location: Flanders, NJ Posts: 259	mark, thanks. I can't remember dropping mine but its possible I could have done something to displace the prizm. I've had water splashed on it and I Know its not completely waterproof. I will call tomorrow and see about possible servicing.

01/05/2014, 09:20 PM	#7
Cloudburst2000 Registered Member Join Date: Nov 2009 Location: Lexington, KY Posts: 1,485	I have the same unit. I have 35ppt calibration solution. I calibrate the digital refractometer with the RODI water, and then I use the 35ppt solution to verify calibration. Sometimes, it is right on the money. Occasionally it is .01 off. When it is off, I just either subtract or add the difference to the water I test with the digital refractometer. I don't use the 35ppt as a calibration solution but as a reference.