Sper Scientific 840020 Light Meter Lux & Foot Candle - Manual (Page 5)

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3-E. Notes and Precautions
• Avoid range overload.
• When using PEAK HOLD (3-C) or REC MAX/MIN (3-D) your
measurements must be within the selected range, if not, the out of
range indicator "- - - -" will be displayed.
• Cover the PHOTO SENSOR (15) with the sensor cap when the meter
is not in use.
• Fluctuations in the reading are often due to shadows or a weak bat-
tery. Also, ambient temperatures and drafts may affect the reading.
• Do not store in areas of high temperature and/or humidity.
• Remove the battery for long-term storage.
4. ZERO ADJUSTMENT AND CALIBRATION
• With the sensor cover securely in place and the meter turned on, use
the RANGE (9) button to select the 40.00 Lux range (digits appear on
the LCD).
• Press the ZERO (10) button and the "0.00
LUX
" should be displayed.
• To maintain accuracy, annual laboratory calibration is recommended
and available from Sper Scientific.
5. BATTERY REPLACEMENT
• Replace the battery when the low battery icon is displayed.
• In-spec measurements may be made for several hours after
the low battery indicator appears.
• Remove the BATTERY COVER (13) screw and slide the cover off.
• Replace the battery with a fresh 9V battery (alkaline or heavy duty).
6. RS232 PC SERIAL INTERFACE
Use a small screwdriver to gently lift the RS232 COVER (6) up to expose
the RS232 OUTPUT (8) 3.5 mm terminal. The signal output is a 16-digit
data stream that can be adapted to user-defined applications. A RS232
lead with the following connection is required to link the instrument with the
PC serial interface.
Meter (3.5 mm jack plug) PC (9W ‘D” Connector)
Center Pin .................................. Pin 4 Pin 2 2.2 K
Ground/shield ............................ Pin 2 Pin 5 resistor