KERN ORF 85BM (01) PDF MANUAL

KERN ORF 85BM (01) PDF SUMMARY:

What is the purpose of the refractometer and what should it not be used for?

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 behavior 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.

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What are some basic safety precautions to follow when using the refractometer?

• Do not let acids come into contact with skin or eyes. If acid comes into contact with skin, flush with copious amounts of water. Shower if larger areas of skin are affected.
• If acid comes into contact with eyes, keep the eyelid open and flush the eye with running lukewarm water from the outer corner to the inner corner. Flush eyes for at least 15 minutes. Then consult a doctor or ophthalmologist immediately.
• Thoroughly clean the refractometer after each use.
• The refractometer must not be exposed to extreme temperatures, high mechanical stresses, strong direct sunlight or high humidity.
• This refractometer is not a toy. Keep out of reach of children.
• Make sure that you will not be hit by anything else while you are using the refractometer, as this could cause serious eye injuries.

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What items are supplied with the refractometer?

• Refractometer
• Storage box
• Pipette
• Screwdriver + batteries
• Cleaning cloth
• Calibration liquid

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How does automatic temperature compensation work in the refractometer?

The refractive coefficient is temperature-dependent. Materials expand when they are heated (their density decreases) and contract when they cool (their density increases). The speed of light through a liquid increases with the temperature and the refractive coefficient therefore decreases. In solid substances this thermal effect has only a minor impact. In liquid substances, however, the change in density is considerable. Automatic temperature compensation ensures accurate measurement results for water-based solutions in relation to the temperature of the sample.

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How to perform a calibration/zero point calibration?

1. Inspect the prism to ensure that the surface is clean and dry.
2. Apply a few drops of the calibration liquid onto the prism window.
3. Press the “→0” button; the measuring instrument begins the zero-point calibration process.
4. The measuring instrument is performing the calibration process when “Scan zero” and a loading bar appear in the display.
5. When the calibration process is complete “Scan Result” and “Pass” is shown in the display in case the calibration was successful. When it was not successful the display shows “Fail”. The calibration result will be saved and will be the new zero point even after the device is powered off and on again.

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How to perform a measurement?

1. Inspect the prism window [4] to ensure it is clean and dry.
2. Apply a few drops of the liquid being examined onto the prism window.
3. Press the, Meas’ button; the instrument begins to measure and the results is shown in the display for 90 seconds.
4. Press the “Meas” button to re-check the previous measurements.

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How to perform a battery change?

When the batteries are fully charged the “Battery symbol” symbol appears at the top right of the display in green color. If the batteries are too weak or almost drained the “Battery symbol” symbol appears at the top right in red color. The batteries should then be replaced. Open the battery cover on the rear and replace the batteries. Always replace both batteries!

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How to switch temperature unit?

The measuring instrument works in Celsius or Fahrenheit. For changing over just press the “→0” button for 2 seconds.

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How do you switch the measuring scale on the device?

1. Hold “Meas” for 2 seconds, the scale will change to the next measurement type.
2. Repeat Step 1 until desired the scale is shown on the screen.

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How to clean and maintain the refractometer?

Clean the refractometer using a soft, lint-free cloth moistened with water, or if necessary alcohol. Do not use any aggressive or abrasive cleaning agents. Never touch the measuring prism [2] with hard tools made from plastic, wood, rubber, metal, glass etc. Hard objects can quickly damage the relatively soft prism glass, resulting in measurement errors. The refractometer is maintenance-free. Cleaning should be carried out immediately before and after each use of the refractometer to maximise its life and optimise measurement results.

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What are the error messages that may show?

Error Message	Description
Fail	Calibration was not successful. Make sure you are using the correct calibration solution and there is sufficient amount and perform the calibration again.
High	Measurement outside of measuring range at top of scale.
Low	Measurement outside of measuring range at bottom of scale.
Temp. 45.0°C	Temperature too high for measuring instrument.
Temp. -10.0°C	Temperature too low for measuring instrument.
Error	No liquid on the prism or not sufficient amount.

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What are the troubleshooting steps to take if the refractometer is not working correctly?

• If you suspect that the measuring instrument is not working correctly or displays incorrect results, perform a zero point calibration.
• Then perform a measurement using water to check the zero point.
• If this does not lead to any improvement, please perform a factory reset by pressing “On/Off” and “Meas” simultaneously and confirming with “→0”.
• If the measured data still appear untrustworthy, please replace the batteries and perform the above calibration once again.
• If the measuring instrument jams or no longer reacts, separate the measuring instrument from the power supply by removing the batteries and replacing them.
• If no data appears in the display when it is switched on, examine the position and polarity of the batteries.
• If the instrument still does not work, please examine the battery charge status and/or replace the batteries.
• If the batteries are good and the measuring instrument still does not display, please call your dealer’s technical customer service.

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What should be the lighting conditions be considered when taking measurements?

It is important to take care of the lighting conditions in the user environment when calibrating the device and subsequent measuring a sample. The measuring prism of the refractometer does not have any coverage and therefore a measurement in addition to the light of the internal light source is also influenced by ambient light.

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What is the effect of the ambient light with the measurement?

Too bright lighting (e.g., by a lamp directly above the device) may trigger an error message already during the calibration. Ordinary (diffuse) light is not a problem.

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Can the lighting condition be changed during measurement?

The lighting conditions (or the location of the device) may not be changed after the calibration or between different measurements, otherwise the refractometer performs each of the processes on a different basis and the results would not be comparable.

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How to avoid influence of ambient light on measurements?

We recommend that both for the calibrations and for measurements, after the sample was placed on the measuring prism, to create an improvised opaque cover over the prism (incl. sample).

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What is the optimal solution temperature and ambient temperature when doing measurements?

The refractometer is temperature-compensated for water-based, sugary solutions. Temperature differences in a range of 5 °C-40 °C (41 °F-104 °F) can be compensated. However, the temperature of the sample has only a minor influence on the accuracy of the measurement. The volume of the sample compared to the mass of the refractometer is so small that in most cases the sample is almost immediately at the temperature of the refractometer and assumes the ambient temperature, and is therefore in equilibrium with the temperature range of the measuring instrument. The temperature coefficient of the majority of water-based solutions is generally very close to the coefficient of the cane sugar / water solution. However, the temperature coefficient of oils, hydrocarbons and other, non-water-based solutions is generally greater. In order to achieve as accurate a result as possible, non-water based samples should be measured at an ambient temperature as close to 20 °C (68 °F) as possible.

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What is the ideal ambient and calibration liquid temperature during calibration?

Ideally, the ambient and calibration liquid temperature should be exactly 20.0 °C (68.0 °F) during calibration.

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What do you need for calibration/zero point calibration?

For the majority of models all you need for calibration/zero point calibration is distilled and deionised water. Calibration liquid with 60% Brix is required for a variety of models.

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When should the calibration function be used?

The calibration function should only be considered when the original condition of the measuring prism or other optical components changes due to wear and tear causing measuring inaccuracies while using the refractometer.

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How often should you do a calibration/zero point calibration?

The models of the ORF series have been calibrated at the factory. In general, this condition does not change even over a long period of usage, when carefully handled. Therefore it is not necessarily needed to carry out any additional calibration before use.

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What are specifications of the refractometer?

1. Temperature range: 0 °C-40 °C (32 F-104 F)
2. Temperature measuring accuracy: +/- 0.5 °C (1 F)
3. Automatic temperature compensation: 5°C – 40°C
4. Minimum volume of sample: Approx. 3 drops
5. Measurement period: ≤ 3 seconds
6. Power supply: 2 x AAA batteries
7. Battery life: ≥ 3,750 measurements
8. Dimensions: 145 x 67 x 38 mm
9. Weight: 185 g
10. Language: English
11. Auto-Off function: after 90 seconds
12. IP protection class: IP 65

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What are the models and specifications?

Model	Scales	Measuring range	Accuracy	Division	Calibration solution
ORF 45BM	Brix	0-45%	± 0.2%	0.1%	0% (distilled water)
ORF 92BM	Brix	58-92%	± 0.2%	0.1%	60% solution
ORF 85BM	Brix	0-85%	± 0.2%	0.1%	0% (distilled water)
ORF 92HM	Brix	58-92%	± 0.2%	0.1%	60% solution
	Baume	38-43 °Be	± 0.1 °Be	0.1 °Be
	Water content	13-25%	± 0.2%	0.1%
	Refractive index	1.4370-1.5233 nD	±0.0003 nD	0.0001 nD
ORF 3SM	Brix	0-35%	± 0.2%	0.1%	0% (distilled water)
	Salt (NaCl)	0-28%	± 0.2%	0.1%
	Refractive index	1.3330-1.3900 nD	± 0.0003 nD	0.0001 nD
ORF 2WM	Mass SW	0-35%	± 0.2%	0.1%	0% (distilled water)
	KMW (Babo)	0-25 °KMW	± 0.1 °KMW	0.1 °KMW
	Oechsle	30-150 °Oe	± 1 °0e	1 °Oe
	Vol. AP	0-22%	±0.1%	0.1%
ORF 1PM	Serum protein	0-12 g/dl	± 0.1 g/dl	0.1 g/dl	0% (distilled water)
	Urine (spec. weight)	1.000-1.050 sgU	±0.001 sgU	0.001 sgU
	Refractive index	1.3330-1.4098 nD	±0.0003 nD	0.0001 nD
ORF 2UM	EG	-50-0°C	±0.5°C	0.1 °C	0% (distilled water)
	PG	-50-0 °C	±0.5°C	0.1 °C
	BF	1.00-1.50 kg/l	± 0.01 kg/l	0.01 kg/l
	CW	-40-0 °C	±0.5°C	0.1 °C
ORF 5UM	EG	-50-0 °C	±0.5°C	0.1 °C	0% (distilled water)
	PG	-50-0 °C	±0.5°C	0.1 °C
	Urea	0-40%	± 0.2%	0.1%
	CW	-40-0 °C	±0.5°C	0.1 °C
ORF 6US	Urea	0-40%	± 0.2%	0.1%	0% (distilled water)
ORF 1RS	Refractive index	1.3330-1.5400 nD	± 0.0003 nD	0.0001 nD	0% (distilled water)

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What is the Brix to Refractive index (nD) conversion table?

BRIX	RI nD	BRIX	RI nD	BRIX	RI nD
0	1.3330	30	1.3812	60	1.4419
1	1.3344	31	1.3830	61	1.4442
2	1.3359	32	1.3848	62	1.4465
3	1.3373	33	1.3866	63	1.4488
4	1.3388	34	1.3885	64	1.4511
5	1.3403	35	1.3903	65	1.4535
6	1.3418	36	1.3922	66	1.4558
7	1.3433	37	1.3941	67	1.4582
8	1.3448	38	1.3960	68	1.4606
9	1.3463	39	1.3979	69	1.4630
10	1.3478	40	1.3999	70	1.4655
11	1.3494	41	1.4018	71	1.4679
12	1.3509	42	1.4038	72	1.4704
13	1.3525	43	1.4058	73	1.4729
14	1.3541	44	1.4078	74	1.4754
15	1.3557	45	1.4098	75	1.4779
16	1.3573	46	1.4118	76	1.4804
17	1.3589	47	1.4139	77	1.4830
18	1.3605	48	1.4159	78	1.4855
19	1.3622	49	1.4180	79	1.4881
20	1.3638	50	1.4201	80	1.4907
21	1.3655	51	1.4222	81	1.4933
22	1.3672	52	1.4243	82	1.4960
23	1.3689	53	1.4265	83	1.4986
24	1.3706	54	1.4286	84	1.5013
25	1.3723	55	1.4308	85	1.5040
26	1.3741	56	1.4330
27	1.3758	57	1.4352
28	1.3776	58	1.4374
29	1.3794	59	1.4397