Hach REFO 60, Руководство пользователя, Страница: 5 / 20

User Manual REFO 60 / REFO 60-D
3
B2 Calibration Standards
For gloss measurement according to DIN 67530 the standard A (LZM 150) is used. This is
a polished black glass tile. For high-gloss measurements (only REFO 60-D), however,
standard metal mirror (LZM 154) is necessary. The calibration values at 60° are found on
the back of the certified standard, together with the standard number which ensures trace-
ability. Do not touch or scratch the standard surfaces. Cover them as soon as they are out
of use and keep them in a safe, preferably dark place.
B2.1
Entering standard number and calibration values
You need only enter a new calibration value after changing the standard. REFO 60-D rec-
ognizes the standard on which it operates. The 4-digit standard number and the reflec-
tometer value for 60° are indicated on the bottom of the standard.

Turn on REFO 60 with the control button , display 60°

Place the instrument on the standard
Hold the control button down for approx. 10 seconds; the display reads
CAL first, then the calibration value XXX.X and at last the standard number
XXXX . To increase the displayed number, press the control button . Then
wait for the next digit to blink.

When the setting is finished, the entire standard number blinks until you acknowledge
the value with the control button.

Now the display shows the blinking calibration value which is to be entered just like
the standard number before.
B2.2
Maintenance of the Calibration Standard
Standards LZM 150 and LZM 154 are provided with a quality control certificates according
to DIN 55350 part 18, 4. The calibration values of the standards remain valid for two years.
Poor accuracy or repeatability of readings is often due to improper handling of the working
standards. Gloss being a surface property, utmost cleanliness is of vital importance. Even
slight irregularities caused by nicotine, dust, fingerprints or scratches can lead to mis-
measurements. The standards can be cleaned carefully with glass cleaning agent and a
soft tissue.
ATTENTION: Do not touch the standard surface with your fingers when cleaning it.
B3 Gloss Measurement
Measuring procedure:

Calibrate REFO 60 (see chapter B1)

Put REFO 60 on the level sample surface

Press the control button .

The display shows the number of measurement first XXX , followed by the current
reflectometer value XXX.X
REFO 60 turns off automatically approx. 2 minutes after the last measurement.