How to adjust refractometer?

[kimha]

Hello

I purchased a used refractometer RHS-10ATC from a member from this site with no manual. Is there a simple way for me to test if this refractometer gives acurate reading? I have a couple of hydrometers and all of them give different readings.

This refractometer has a little knob for adjustment. But have no instruction on how to adjust it. I am guessing I can use bottle drinking water and check the reading. If it is not at zero I will adjust it to read zero? Is this how it works?

Any help is greatly appreciated.

Kimha

 

[Douglas LEHMAN]

Hello
Thats it, some adjust with a small screwdriver. Just use RO water at room temp., same temp. as the refractometer.

 

[kimha]

Thanks Doug. I have no RO water. Can I use water from drinking bottle?

 

[ostrow]

No, that is mineral water and will not have a zero salinity level. You need RO/DI water. Distilled water will work.

 

[kimha]

Thanks much. I will look for distill water at a grocery store and give it a try.

 

[jun_celis]

Distilled water is actually the recommended in my refractometers instructions to calibrate it.

 

[Rod Buehler]

you should also chech the chemistry forum for RHFs receipe to make a standard 35ppt solution for calibration. Table salt and a 2 liter bottle is basically all you need.