General Tools DREF-UP320 User Manual

Operation Manual

DREF/UP320 (DR303) Portable Digital Refractometer

The Brix concentration, Refractive index or other parameters are always needed in lab or our life. Optical
refractometer is very popular used to measure these parameters. The Digital refractometer with a digital
readout and LCD display will eliminate uncertainties and is more convenient to use. Just about 0.3ml-0.5ml
sample was needed. All our digital refractometers have the following characters:

z Automatic Temperature Compensation
z Automatic Shut Off after 3 minutes
z Conversion between Centigrade and Fahrenheit Degree
z Alarm of Low Voltage & Low power consumption
z Temperature Measurement Range：0℃－40℃（32℉－104℉）
z Precision of Measurement temperature：±0.1℃(2℉)
z Measurement temperature Resolution：0.1℃(2℉)
z Operation Temperature：0℃－40℃（32℉－104℉）
z Storage temperature：-10℃－50℃ （14℉－122℉）
z Dimension ：185×59×45mm
z Weight：230g
z Power Supply：1battery（9v）
z Operating Time：More than 1500 times per battery

ⅠParts:

Ⅱ Installation Battery:

In the case of no battery or low battery with alert of “(((“ on the upper left of LCD, you should install or
replace the battery. Open the battery cover on the back of the instrument, install a battery or replace the old
battery with a new one.

Ⅲ Power On and Off:

Press the “On/Off” button to turn it on or off. Temperature in Centigrade will
display when power on. The instrument will turn off automatically if there is no
any operation in three minutes.

Ⅳ Measurement of Temperature:

Temperature can be displayed at any time by press the “Temp” button during measurement.
The conversion between Fahrenheit and Centigrade can be made by pressing “Temp” button.

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ⅤConversion of Status of Scales:

1. Turn it of f: Press the “On/Off” button to turn refractometer OFF.

2. Synchronously hold “Blank” button and “Mes” button.

3. Turn it on: Press the “On/Off” button to turn refractometer ON.

4. Repeat step 1-3 to set other scale.

Please be NOTICED: The chosen status of scale will be stored no matter if power off.

Ⅵ Original Point Setting:

1. Completely clear prism window

2. Drop standard solution to fill the prism window

3. Hold “Blank” button for Five seconds till it twinkles “rEF” on LCD

Hold 5 seconds

4. Within 10 second after display “rEF”, press “Mes” button and hold it for Five seconds.

5. The instrument start to set Original Point. After Original Point, Setting is
finished. “End” will be displayed on LCD.

Please be NOTICED: Be sure power of battery is sufficient and environment temperature is between 10-30
Centigrade degree. 18-22 Centigrade degree is better to get high zero precision after Original Point Setting.
Original Point setting can be operated under any scale status. Please find Original Point List in last page.

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Hold 5 seconds