KERN ORM 2UN Digital Refractometer
INSTRUCTION MANUAL
Carefully read through the operating manual even if you have prior experience with KERN refractometers
1. General information
1.1 Intended use
The refractometer is a measuring instrument for determining the refractive index of transparent substances in liquid or in some cases also in the solid state. It is used to observe the behaviour of light as it passes from a prism with known properties to the substance being tested.
Use of the refractometer for other purposes is contrary to its intended use and may be hazardous. The manufacturer shall not be liable for any damages caused by improper use.
1.2 Warranty
The warranty shall be void in the event of:
▸ Failure to observe the instructions in the operating manual
▸ Use for purposes other than those described
▸ Modifications or opening the device housing
▸ Mechanical damage and/or damage resulting from media, liquids, natural wear and tear
This digital refractometer cannot measure any liquid that is highly corrosive to metal or glass. When measuring liquids that are corrosive to plastics or react chemically with plastics, be careful not to drop the measured liquid onto the shell. Otherwise it will corrode the shell.
2. Introduction
2.1 Description
2.2 Scope of delivery
1x Strorage box | 1x Digital refractometer | 1x Operating manual | 1x AAA Battery 1.5 V | 1x Pipette | 1x Screwdriver
3.1 Description display & operating buttons
Note：Please replace the battery when the 
is displayed.
4. Preparing before operating
4.1 Install the battery
5. Turn on & measure
5.1 Turn on
Note :
1. When used outdoors, please avoid strong light so as not to affect the measurement accuracy.
2. Please keep the instrument in a stable and still statement and position.
5.2 Measure
After turning on, clean the sample tank with distilled water and then dry it. Now fill the sample up to the mark, close the cover and press “READ”.
5.3 Average value measurement
Press “READ” for 2 seconds. The device starts an automatic measurement series of 15 measurements and shows the average value.
Afterwards, the device automatically turns back to the normal measuring mode.
6. Calibration
The refractometer can only be calibrated with distilled water. To do this, fill the sample tank with distilled water up to the mark and close the cover.
While “CAL” is flashing in the display, press “CAL” again to start the calibration. When the calibration is finished, the display shows “End”.
After approx. 10 seconds, the device automatically returns to normal mode.
We recommend calibrating the refractometer,
- when commissioning
- after a strong shock
- after longer transport
- after a change of location with a large temperature difference
- if the device has not been used for a long time
Always use distilled water and make sure that the refractometer, the water and the environment are at the same temperature.
7. Changing scale & termperature unit
7.1 Changing scale
7.2 Changing termperature unit
If exceed the temperature limitations, the signs “HHH” or “LLL” would show
8. Turning off
If without any operations for 1 minute, the instrument would be automatically turned off
9. Cleaning & maintenance
1. To avoid damages to the prism and the sample tank, clean them with distilled water after each use.
2. Dry it with a soft cloth afterwards.
3. Do not use hard or abrasive objects for cleaning.
4. Do not leave any residue in the sample tank.
5. If the refractometer is not going to be used for a longer time, remove the battery and store it at a We recommend calibrating the refractometer, cool and dry place.
10. Disposal
The packaging consists of environmentally friendly materials which can be disposed of via local recycling facilities.
The device and storage box should be disposed
11. Technical data
| Scale +accuracy+ resolution | Oepents to the model | |||
| Temperature | o,o -40,o•c / 32,o- 104,o’F | |||
| AutomaticTemperature Compensation | Yes | |||
| Minimumsample volume | 0.2 – 0.3 ml (Marking ring) | |||
| AUTO-OFF | 60 seconds | |||
| Averagingmeasurement | 15measurements | |||
| Banery | 1 xAAA 1.5 V | |||
| Lifetime of thebattery | Approx. 10.000 measurements | |||
| Overall dimensions LxWxH | 12Sx6Sx30 mm | |||
| Net weight | 140 g (without battery) | |||
12. Error codes
| A01 | Beyond the scope of calibration temperature. (0.0°C~40.0°C) | |||
| A02 | During calibration, no solution or solution wrong. | |||
| A03 | This instrument has a hardware failure. | |||
| Model | Scale | No. | Range | Unit | Resolution | Accuracy | |
| ORM 50BM | Brix | S01 | 0.0~50.0 | % | 0.1% | ±0.2% | |
| Refractive Index | S02 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| ORM 1RS | Brix | S01 | 0.0~90.0 | % | 0.1% | ±0.2% | |
| Refractive Index | S02 | 1.330~1.5177 | nD | 0.0001nD | ±0.0003nD | ||
| Fructose | ORM 1SU | Fructose | S01 | 0.0~68.9 | % | 0.1% | ±0.2% |
| Glucose | S02 | 0.0~59.9 | % | 0.1% | ±0.2% | ||
| Brix | S03 | 0.0~90.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.5177 | nD | 0.0001nD | ±0.0003nD | ||
| ORM 2SU | Lactose | S01 | 0.0~16.5 | % | 0.1% | ±0.2% | |
| Maltose | S02 | 0.0~15.6 | % | 0.1% | ±0.2% | ||
| Dextran | S03 | 0.0~10.6 | % | 0.1% | ±0.2% | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Honey | ORM 1HO | Honey Water | S01 | 5.0~38.0 | % | 0.1% | ±0.2% |
| Honey Baume | S02 | 33.0~48.0 | °Bé | 0.1 | ±0.2 | ||
| Brix | S03 | 0.0~90.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.5177 | nD | 0.0001nD | ±0.0003nD | ||
| Salinity | ORM 1NA | Salinity (NaCl) % | S01 | 0.0~28.0 | % | 0.1% | ±0.2% |
| Salinity (NaCl) ‰ | S02 | 0~280 | ‰ | 1‰ | ±2‰ | ||
| Specific Weight | S03 | 1.000~1.220 | – | 0.001 | ±0.002 | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S05 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| ORM 1SW | Salinity Seawater | S01 | 0~100 | ‰ | 1‰ | ±2‰ | |
| Chlorinity Seawater | S02 | 0~57 | ‰ | 1‰ | ±2‰ | ||
| Specific Weight | S03 | 1.000~1.070 | – | 0.001 | ±0.002 | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S05 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Alcohol | ORM 1AL | Alcohol Mass. | S01 | 0~72 | % | 1% | ±1% |
| Alcohol Vol. | S02 | 0~80 | % | 1% | ±1% | ||
| Brix | S03 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Beer | ORM 1BR | Plato | S01 | 0.0~30.5 | °P | 0.1 | ±0.3 |
| SG Wort | S02 | 1.000~1.130 | – | 0.001 | ±0.002 | ||
| Brix | S03 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Wine | ORM 1WN | Oechsle | S01 | 0~150 | °Oe | 1 | ±2 |
| Vol% | S02 | 0.0~22.0 | % | 0.1% | ±0.2% | ||
| KMW (Babo) | S03 | 0.0~25.0 | – | 0.1 | ±0.2 | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| ORM 2WN | Oechsle France | S01 | 0~230 | °Oe | 1 | ±2 | |
| Vol% | S02 | 0.0~22.0 | % | 0.1% | ±0.2% | ||
| KMW (Babo) | S03 | 0.0~25.0 | – | 0.1 | ±0.2 | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Coffee | ORM 1CO | Coffee TDS 1 | S01 | 0.0~25.0 | – | 0.1 | ±0.2 |
| Brix | S02 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S03 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| ORM 2CO | Coffee TDS 2 | S01 | 0.00~25.00 | – | 0.01 | ±0.20 | |
| Brix | S02 | 0.00~30.00 | % | 0.01% | ±0.20% | ||
| Refractive Index | S03 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Urine | ORM 1UN | Urine Human | S01 | 1.000~1.050 | – | 0.001 | ±0.002 |
| Serum Protein | S02 | 0.0~12.0 | g/100ml | 0.1 | ±0.2 | ||
| Brix | S03 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| ORM 2UN | Urine Cat | S01 | 1.000~1.060 | – | 0.001 | ±0.002 | |
| Urine Dog | S02 | 1.000~1.060 | – | 0.001 | ±0.002 | ||
| Brix | S03 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S04 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Car / Industry | ORM 1CA | Cleaner | S01 | (-60.0)~0.0 | °C | 0.1℃ | ±0.5℃ |
| AdBlue® | S02 | 0.0~51.0 | % | 0.1% | ±0.2% | ||
| Battery Fluid | S03 | 1.000~1.500 | – | 0.001 | ±0.005 | ||
| Brix | S04 | 0.0~50.0 | % | 0.1% | ±0.2% | ||
| Refractive Index | S05 | 1.3330~1.4200 | nD | 0.0001nD | ±0.0003nD | ||
| Ethylenglycol (%) | S01 | 0.0~100.0 | % | 0.1% | ±0.5% | ||
| Ethylenglycol (°C) | S02 | (-50.0)~0.0 | ℃ | 0.1℃ | ±0.5℃ | ||
| Propylenglycol (%) | S03 | 0.0~100.0 | % | 0.1% | ±0.5% | ||
| ORM 2CA | Propylenglycol (°C) | S04 | (-60.0)~0.0 | °C | 0.1℃ | ±0.5℃ | |
| Brix | S05 | 0.0~90.0 | % | 0.1% | ±0.2% |
Specifications
- Measuring instrument: Refractometer
- Measurement type: Refractive index of transparent substances
- Display: LCD Multi-function display
- Material: Stainless steel sample tank
- Power source: 1.5V AAA Battery
Frequently Asked Questions (FAQ)
Q: What should I do if an error code is displayed?
A: Check the error code in the manual to identify the issue. If needed, recalibrate the refractometer following the calibration instructions.
Q: Can the refractometer measure highly corrosive liquids?
A: No, the digital refractometer cannot measure liquids highly corrosive to metal or glass. Be cautious with liquids corrosive to plastics to avoid damaging the device.
Documents / Resources
 |
KERN ORM 2UN Digital Refractometer [pdf] Instruction Manual ORM 2UN, P -V1.5.240906, ORM 2UN Digital Refractometer, ORM 2UN, Digital Refractometer, Refractometer |
