Sper Scientific 840006 Light Meter Lux User Manual
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3. MEASUREMENT PROCEDURES
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Insert the SENSOR plug into the SENSOR INPUT socket.
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Turn the meter on using the ON button.
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Remove the lens cap from the PHOTO SENSOR.
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Press the 1X button for measurements of 0 ~ 1999 LUX, or select the
10X button for measurements of 2,000 ~ 19,990 LUX. If you are
uncertain about which range to use, select the highest range. In 10X
mode, " " appears in the right bottom LCD.
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Range Overload is indicated when "1" appears on the left side of the
display. If this occurs, switch to the highest range or discontinue use.
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Point the PHOTO SENSOR toward the source and read the results on
the display. To convert LUX results to FC, multiply the meter reading by
the factor of .0929
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Push the HOLD button to freeze the reading in the display. The word
"HOLD" is displayed. Press the HOLD button again to exit this function.
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Press the OFF button to turn the unit off.
NOTES:
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Keep the lens cap on the PHOTO SENSOR at all times except when
actually taking a reading.
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Fluctuations in the reading are generally due to shadows or fluctuations
in the line voltage. Ambient temperature, drafts and ventilation also
affect the luminous flux output.
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Avoid range overload and do not store in areas of high temperature
and/or humidity. Remove the battery for long-term storage.
4. ZERO ADJUSTMENT & CALIBRATION
WARNING: Only use the terminal marked "ZERO" for adjustment.
The unmarked terminals are for professional laboratory calibration only and
tampering with these terminals will result in inaccurate readings and require
professional calibration of the meter.
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With the sensor cover securely in place and the meter turned on, the
LCD display should indicate "0000". A slight variation will not affect
readings; however, if a precise reading is required you may use the
ZERO SETTING terminal to reset the unit.
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To make an adjustment, cover the PHOTO SENSOR and press the
1X button.
•
Use a small screwdriver to turn the ZERO SETTING terminal until
"0000" is displayed.
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To maintain accuracy, annual laboratory calibration is recommended.