Question and Answer Forum

MISCO Refractometer Q&A Forum

Find answers to many common questions concerning applications, operation, calibration, and maintenance of refractometers:

Antifreeze & Heat Transfer (23)

Please advise if you have a meter that can measure glycol concentration in water? It will be used in a food processing industry.

We have two different types of refractometers that you can use to measure glycol concentration in water. The first is the MISCO 7084VP+ Glycol & Battery Tester. It is a traditional analog refractometer with scales for measuring both ethylene glycol (EG) and propylene glycol (PG) freeze points. For more accuracy, the MISCO Palm Abbe digital refractometer can be equipped with a number of scales for reading ethylene glycol (EG) and propylene glycol (PG). You may select from scales for measuring freeze point, concentration by weight or volume, specific gravity, density, and even boiling point. The Palm Abbe PA203X digital refractometer can be equipped with up to five different scales.

Hello, I am looking for a handheld portable device to measure the % mass ethylene glycol in a glycol / water solution. Thanks.

The MISCO Palm Abbe digital refractometer can be programmed with scales for measuring the percent by weight or percent by volume of ethylene glycol (EG) in an ethylene glycol (EG) / water solution. Just use the filters in the digital handheld refractometer section of the MISCO website to find the refractometer that is right for you. If you don’t see what you need, please contact MISCO customer service and we will create a custom refractometer to your specifications.

 

I need a refractometer to check Glycerin, and possibly propylene glycol. What handheld palm abbe would be best for me? The PA202 or PA203 Will the PA202 measure glycol? Does the pa203 come with pre-installed scales or custom scales for each use? My application is for antifreeze. Fahrenheit readings please. Please advise.

With the right combination of scales, either the Palm Abbe PA202x or PA203 digital refractometer will handle the job of measuring glycerin and propylene glycol antifreeze solutions. Scales are available to read nearly any physical property of glycerin and propylene glycol, including scales for freeze point and concentration or other units of measure such as specific gravity, density, percent by weight or volume, and more.

Do you have any refractometer that can tell whether an unknown liquid is glycol or glycerin?

No, unfortunately a refractometer cannot tell the difference between glycol and glycerin. Although we do have refractometers with both glycol and glycerin scales, you must know which fluid you are testing and test it on the correct scale to get an accurate measurement of concentration or freeze point.

I have some questions about your 7084VP+ MISCO glycol and battery tester. How would I use this refractometer to verify a 30% glycol solution in one of our systems since the unit it reads are in degrees Fahrenheit?

You have two choices. First, ask your glycol supplier for a chart of glycol concentration to freeze point. They will be happy to supply you with one. Then measure the freeze point of the fluid with the 7084VP+ and look up the percent concentration corresponding to your freeze point measurement.

Can the Palm refractometer be used to check Trieythelene Glycol?

Thanks for your question. The Palm Abbe digital refractometer can measure several triethylene glycol (TEG) physical properties including, percent by weight, percent by volume, freeze point, specific gravity, density, and boiling point.

What is the difference between the traditional analog Brix refractometer and the electronic digital handheld for Glycol testing? What are the benefits to having one over the other?

This is a good question. Brix is a measure of sucrose content in a sucrose water solution. There is not a direct linear relationship between Brix and glycol concentration. However, there may be a conversion chart available from your glycol supplier or you can make your own (we do not have conversion charts). Our analog Brix refractometer has a precision of +/- 0.2% Brix. The analog refractometer scale is subjective, meaning that two or more people looking at the scale are likely to report different readings depending how they view the scale. You also need to bring the glycol near your face to take a reading. Brix refractometers are temperature compensated for sucrose not glycol. Lastly, since you need to use a conversion table to manually calculate glycol freeze point, you introduce the possibility of making an error. A Palm Abbe digital refractometer with a scale for glycol would be a much better choice. First, the reading is digital which removes subjectivity from the measurement. Second, you can read directly in the unit of measure you desire, concentration or freeze point. This eliminates conversion errors. Since you place your sample in a well, you do not need to bring the refractometer near your face to read it. Also, a digital refractometer with a glycol scale will have temperature compensation specific to glycol. Lastly, the Palm Abbe digital refractometer has at least twice the accuracy of an analog Brix refractometer.

What are all the different salt scales used for? I need to measure salinity content but don’t know what scale I need.

Chemically, salts are ionic compounds that result from the neutralization reaction of an acid and a base. There are several varieties of salts containing chlorides, acetates, fluorides, and sulfates. The most common salt is sodium chloride (NaCl) or regular table salt. Although we have a refractometer scale that will measure most common salts, we also have an extensive list of scales for sodium chloride. You may select from scales for measuring sodium chloride concentration in percent by weight, specific gravity, freeze point, parts per thousand (ppt), g/100g, density, percent saturation, and even Baume. The most common units of measure are percent by weight, percent saturation, and freeze point. The scale that is correct for you depend on what unit of measure you are most interested in. Multiple salt scales can be programed into the MISCO Palm Abbe digital refractometer so you can just change between different units of measure as your needs change. MISCO also has scales available for the salinity of seawater.

Hi, will your hand held (both glycerin/ glycol) read below zero. In Utah we are required to provide -0 readings. Please let me know.

The glycerin scale on the Palm Abbe digital refractometer can measure the freeze point of glycerin from +32 to -46 °F. It can read glycerin concentration from 0 to 100%. The propylene glycol scale for this refractometer can measure propylene glycol freeze point from +32 to -60 °F. It can also read propylene glycol concentration from 0 to 100%.

I need to know the percent volume of my glycol?

.There are two methods to determine the percent concentration of glycol in a system. If using the MISCO Glycol & Battery Tester (7084VP or 7064VP), take a reading of the glycol on the freeze point scale and then cross reference the freeze point reading to the percent volume column on a physical property chart, available from your glycol supplier. If using one the MISCO Palm Abbe digital handheld refractometer, there are several scales available which directly display the concentration by volume of a glycol solution.

I need to detect Ethylene Glycol contamination in rain water as it flows through a pipe, in order to detect leakage from a heat-transfer system. I don’t need a measurement, simply a yes or no signal. Is this something you can supply?

The best method to detect low levels of ethylene glycol contamination in rain water is with the MISCO Palm Abbe digital refractometer. Equipped with one of several ethylene glycol scales the Palm Abbe refractometer can detect ethylene glycol to +/-0.1%. Refractometer scales are available for measuring ethylene glycol percent by weight, percent by volume, freeze point, specific gravity, density, and boiling point.

Products

Ethylene Glycol Refractometer – Ethylene Glycol Scales -Concentration & Freeze Point °C – MISCO Digital Refractometer

Ethylene Glycol Refractometer – Ethylene Glycol Scales – Concentration & Freeze Point °F-MISCO Digital Refractometer

I need a refractometer to check Glycerin, and possibly propylene glycol. What handheld palm abbe would be best for me? The PA202 or PA203 Will the PA202 measure glycol? Does the pa203 come with pre-installed scales or custom scales for each use? My application is for antifreeze. Fahrenheit readings please. Please advise.

With the right combination of scales, either the Palm Abbe PA202x or PA203 digital refractometer will handle the job of measuring glycerin and propylene glycol antifreeze solutions. Scales are available to read nearly any physical property of glycerin and propylene glycol, including scales for freeze point and concentration or other units of measure such as specific gravity, density, percent by weight or volume, and more.  You can combine your own scale choices with our build your own tool, or consider the below products.

Glycerin-Propylene Glycol Refractomete- Glycerine- Propylene Glycol Scales-Percent Volume – Freeze Point °C- MISCO Digital Refractometer

Glycerine-Propylene Glycol Refractometer – Glycerine & Propylene Glycol Scales – Percent Volume – Freeze Point °F – MISCO Digital Refractometer

I am wanting to find out if you have a handheld meter that can measure: TEG EG DEG PG MEA DEA DGA Any assistance that you can provide would be greatly appreciated.

Scales are currently available for the Palm Abbe digital refractometer that can measure EG (ethylene glycol), PG (propylene glycol), TEG (triethylene glycol), DEG (diethylene glycol), MEA (Monoethanolomine), DEA (Diethanolomine), and DGA (Diglycolamine). Please contact MISCO customer service for details on ordering, or see the Build-Your-Own section of our website.

I am looking for an refractometer to measure & control concentration of salt brine preparation for road deicing (at 23.3 %). Is your refractometer applicable to this service?

We have two options for your brine maker. First, is the Palm Abbe digital refractometer with scales for sodium chloride (NaCl). Scales are available for salt concentration as percent by weight, parts per thousand (ppt), or percent (%) saturation. There are also scales available for testing the freeze point of your brine solution. We also have scales available for measuring calcium chloride, urea, and magnesium chloride as well. The Palm Abbe can have up to five different scales so one refractometer can measure the concentration of all your deicing fluids. The second option, would be installing an inline refractometer on your brinemaker to monitor salt brine concentration in real-time. A 4 to 20 mA on the inline can be wired to a PLC and can open or close valves to draw off salt brine when it is at the proper concentration. The inline unit can measure sodium chloride, calcium chloride, and magnesium chloride.

Sodium Chloride Salt Brine Refractometer Salomete-; Sodium Chloride Salt Brine-Percent Saturation- Freeze Point in °C – MISCO Digital Refractometer

Sodium Chloride Salt Brine Refractometer Salometer- Sodium Chloride Salt Brine- Percent Saturation- Freeze Point in °F -MISCO Digital Refractometer

I would like to obtain some additional information regarding your PALM ABBE PA202X-011-014 ethylene glycol refractometer. Our enquiry is related to the use of the refractometer for measuring runoff and surface waters for ethylene glycol. Specific questions are:

1. Units of measure. Does the instrument have the capability of reporting measurements in mg/L?

mg/L is a tough number to display on the refractometer. Refractometers typically measure in the parts per thousand range. Mg/L is parts per million. This is well beyond the detection threshold of most handheld refractometers.

2. What is the range (lower detection limit and upper limit) of detection of the instrument in mg/L?

0 to 1,000,000 mg/L Theoretical.

3. If there is an upper range, is there a procedure specified for sample dilution?

Upper range would be 100% EG. No dilution would be necessary.

4. Are there any properties of the matrix (water) that may interfere with the analyses (e.g., suspended solids, dissolved solids, pH)?

Dissolved solids are additive to refractive index. Any dissolved solids besides EG would cause an error in the reading. Most suspended solids should have no effect on the readings.

5. What is the precision and accuracy of the measurements (+/- in terms of mg/L)? Does the accuracy/precision vary according to sample concentration?

The average full scale precision would be approximately +/- 1.500 mg/L.  and Yes. It is approximately +/- 1.395 at the bottom of the scale and +/- 3.966 at 100% EG.

We are interested in determining the level of ethylene glycol and triethylene glycol in the field and wonder if the PA203 is suitable to do that.

Yes, scales are available for the Palm Abbe digital refractometer for measuring both ethylene glycol (EG) and triethylene glycol (TEG). TEG scales are available for measuring percent by volume, percent by weight, freeze point, specific gravity (D20/20), and density. The same scales are available for ethylene glycol plus boiling point and percent water content. You can mix and match any five of these scales in the Palm Abbe PA203.

A vendor gave me your website to try and locate a meter that could tell me the percentage of Diethanolamine contained in a deionized water solution. We typically run approximately 25-30% DEA solution, and add deionized water or diethanolamine (DEA) to maintain this concentration. Do you provide a hand-held instrument that could analyze this for us?

Thanks for your question. The Palm Abbe digital refractometer can be programmed with scales to read Diethanolamine (DEA) from 0 to 100 percent by weight. Just place a few drops of Diethanolamine (DEA) on the measuring surface, close the evaporation cover, and press the button to get an instant reading of concentration.

What is the difference between freezepoint and burst point when testing with a refractometer.

Freezepoint is the point that the first ice crystals form in the absence of supercooling. Burst point is the point that the solution freezes solid and bursts the vessel containing it. The burst point is usually 30-50 degrees colder than the freezepoint. Our Glycol & Battery Tester reads the freezepoint of both ethylene and propylene glycol solutions. If you need to know the burst point, take a reading on the Glycol & Battery Tester and use a chart (available from your antifreeze supplier) to cross-reference freezepoint to burst point or percent concentration.

When using this to test % PG in water, is it possible to get a false positive at low levels (e.g., 0.1, 0.2)? Does the turbidity of the sample have any effect?

The uncertainty of the Palm Abbe digital refractometer PA203X with a propylene glycol (PG) scale is +/-0.1%. So, if you are testing pure water there is always the possibility of receiving a reading of either -0.1% or +0.1% concentration. To minimize the possibility of an erroneous reading, you can take multiple readings and average them together. Generally, turbidity caused by suspended solids will have little effect on refractive index measurement.

Full question

We just purchased a MISCO digital salometer for measuring sodium chloride concentration. We have a process that needs to mix DI water with Sodium Chloride (NaCl) to 100% saturation. I am hoping that the meter I have bought is the correct version for this job?

The MISCO Digital Salometer is a refractometer that measures the percent saturation of sodium chloride (NaCl) salt in water. The refractometer will display the percent saturation of sodium chloride from 0 to 100% as well as display the freeze point of the solution in either Fahrenheit or Celsius (model dependent). A digital Salometer overcomes many of the problems associated with traditional analog Salometers. Traditional Salometers are cumbersome to use and time consuming. They are simply a glass or plastic hydrometer with a special scale that displays degrees SAL instead of specific gravity. In use, the traditional Salometer is floated in a graduated cylinder containing salt brine. The reading is taken at the point at which the surface of the fluid crosses the analog scale divisions; the temperature must then be read with a thermometer, followed by a manual temperature correction of the reading.

There is no method for field calibrating the apparatus; it is difficult to resolve the tiny scale divisions; it must be thoroughly cleaned and dried to prevent salt residue from influencing subsequent readings; and it is easily broken. The MISCO Digital Salometer is much easier to use and much more accurate. Simply place a couple of drops of sodium chloride solution on the measuring surface, close the evaporation cover, and press the button to initiate the readings. The percent saturation is displayed nearly instantly on the large LCD display.

Products

Sodium Chloride Salt Brine Refractometer Salometer,  Sodium Chloride Salt Brine , Percent Saturation , Freeze Point in °C

Sodium Chloride Salt Brine Refractometer Salometer,; Sodium Chloride Salt Brine,; Percent Saturation Freeze Point in °F

 

We have a pool with 18% salt (a mixture of NaCl, CaCl2 and MgCl2). Is there a digital device [refractometer] that can measure the % of salt in the water?

I have some concerns about your ability to measure percent salt in a multi-component mixture with a refractometer. You see, refractometers are very good at measuring binary (two-part) mixtures such as sodium chloride and water, where the refractive index value of water is a constant (static or known) and sodium chloride is the variable. However, when there are many different components in a solution, such as sodium chloride (NaCl), calcium chloride (CaCl2), and magnesium chloride (MgCl2), it is difficult to tell what the contribution is that each component makes to the total refractive index.

So, if the refractive index changes, it is impossible to say, with any certainty, which of the component parts has changed. Since a refractometer only measures the total refractive index of a solution and cannot selectively read the refractive index of one particular component. All water soluble fluids look the same to the refractometer. Therefore it will be impossible to get a reading that is meaningful.

The Palm Abbe refractometer does have scales for binary solutions of sodium chloride (NaCl), calcium chloride (CaCl2), and magnesium chloride (MgCl2), but cannot measure a mixture of all three.

I have a gas dehydration system which used TEG. Typical concentrations of Tri-ethylene Glycol (TEG) vary from 88% to 98%. Do you have a device that could measure the concentration of TEG to within +/- 0.5%. The typically impurities are 1) water ( 2-12%) and 2) oil (300- 1000 ppm). Thanks in advance.

No problem. Our Palm Abbe digital refractometer can measure the percent concentration of triethylene glycol (TEG) in your dehydration system from 0 to 100 percent (+/- 0.1%). You can choose a scale for TEG percent by concentration or TEG percent water. The oil contaminate should not be a problem because the refractometer only measures in the parts per thousand (ppt) range, not in parts per million.

 

Can I check the glycol water ratio in ice rink using a refractometer? If yes, please tell me which type and also from where I can get your meter.

Propylene glycol is the heat transfer fluid of choice for most ice rinks. We have several propylene glycol refractometers to choose from depending on your preferences and budget. One is the MISCO 7084VP+ Glycol & Battery Tester. The 7084VP+ is a traditional analog refractometer with freeze point scales for both ethylene glycol and propylene glycol. The other alternative is one of several versions of the MISCO Palm Abbe digital handheld refractometer.

Choose from propylene glycol models with scales for freeze point and concentration or other units of measure such as specific gravity, density, percent by weight or volume, and more. To view our complete line of propylene glycol refractometers, you can select the platform of interest and use the filters to limit the selection until you find what you need. Alternatively, you can use the Build Your Own Refractometer section to select the exact propylene glycol scales that you need.