
Thank you for purchasing a Field ScoutTM Light Meter. This
manual describes the features and operation of the following
meters:
3415F Quantum Light Meter (Solar Calibration)
3415FQF Quantum and Foot-Candle Meter
3415FSE Dual Solar/Electric Quantum Meter
Using the Meter
1. Turn the dial clockwise to the “ON” position. Dual mode
meters (3415FQF, 3415FSE) have two “on” settings, one
to either side of “OFF”.
2. Hold the meter vertical for accurate readings.
3. Turn the meter off after use to conserve battery power.
Changing the Battery
The Field Scout Light Meters use a standard 9V battery. To
change the battery:
1. Remove the two screws on the back of the meter.
2. Lift the back from the bottom of the meter.
3. Remove the old battery from the connector, and snap the
new battery in its place. Set the battery into the front half
of the case.
4. Connect the front and back of the case at the top (by the
sensor).
5. Close the case and tighten the two screws.
Accuracy
The Field Scout Light Meters are accurate to ±5%. Cosine
correction is accurate to ±3% at 45°, and ±7% at 80°.
(800)248-8873 or (815) 436-4440 between 7:30 am and 5:00 p.m. CST
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For support, or to place an order, call:
Spectrum Technologies, Inc
12360 S. Industrial Dr. East
Plainfield, IL 60585
e-mail: info@specmeters.com.
www.specmeters.com

A quantum is the amount of energy possessed by a photon.
Photosynthesis is driven primarily by light in the range between 400 and 700 nanometers, which is referred to as Photosynthetically Active Radiation, or PAR light. The intensity of
PAR light is referred to as Photosynthetic Photon Flux Density (PPFD), which is measured in units of µmol m
-2 s-1
(the
number of photons in units of micromoles, striking an area
one meter square each second). Quantum Light Meters are
calibrated to display PPFD. The meters display PPFD in the
range 0-1999 µmol m
-2 s-1
.
Field Scout Quantum Light Meters are calibrated for sunlight.
Due to differences in the spectrum generated by artificial
lights, the following adjustments must be made in the value
shown on a sunlight-calibrated meter:
Fluorescent: reads 8% high, so multiply the display by 0.92.
Metal Halide: reads 6% high, so multiply the display by 0.94.
High Pressure Sodium: 0% error—no adjustment needed.
Sunlight: 0% error—no adjustment needed.
Note that the 3415FSE meter displays accurate readings for
fluorescent lights when set to “Electric”.
The chart below displays the spectral response of the Quantum Light Meters.
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The 3415FQF Quantum and Foot-Candle Meter measures
both PAR light, and light intensity as perceived by the human
eye. The eye perceives light of approximately 560 nm most
strongly, with perception half that at 500 and 600 nm.
The meters display values in the range 0-1999. This must be
multiplied by 10 to obtain Foot-Candles, so the meter range is
0-19990 Foot-Candles. Since 1 Foot-Candle is equivalent to
approximately 10.8 lux, multiplying the meter reading by 108
will compute lux.
Warr anty
The Field ScoutTM Light Meters are warranted to be free from
defects in materials and workmanship for a period of 1 year from
the date of original purchase. During the warranty period,
Spectrum will, at its option, either repair or replace products that
prove to be defective. This warranty is void if the product has been
damaged by customer error or negligence, or if there has been an
unauthorized modification.
Returning Products to Spectrum
Before returning a failed unit, you must obtain a Returned Goods
Authorization (RGA) number from Spectrum. You must ship the
product(s), properly packaged against further damage, back to
Spectrum (at your expense) with the RGA number marked clearly
on the outside of the package. Spectrum is not responsible for any
package that is returned without a valid RGA number or for the loss
of the package by any shipping company.
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