Non-destructive measurement of plant chlorophyll

The SPAD-502Plus enables quick, easy measurement of the chlorophyll content of plant leaves without damaging the leaf. Chlorophyll content is one indicator of plant health, and can be used to optimize the timing and quantity of applying additional fertilizer to provide larger crop yields of higher quality with lower environmental load.


Type Chlorophyll Meter SPAD-502Plus
Measurement subject Crop leaves
Measurement method Optical density difference at 2 wavelengths
Measurement area 2 mm × 3 mm
Subject thickness 1.2 mm maximum
Subject insertion depth 12 mm (with stopper having position adjustable from 0 to 6 mm)
Light source 2 LED elements
Receptor 1 SPD (silicon photodiode)
Display LCD panel showing 4-digit measurement value (values shown to first decimal place) and 2-digit number of measurements; Trend graph of values in memory can also be shown.
Display range -9.9 to 199.9 SPAD units
Memory function Memory capacity for up to 30 values; Calculation/display of average of data in memory also possible
Power source 2 AA-size alkaline batteries
Battery life More than 20,000 measurements (when using new alkaline batteries under Konica Minolta test conditions)
Minimum interval between measurements Approx. 2 seconds
Accuracy Within ±1.0 SPAD units (for SPAD value between 0.0 and 50.0 under normal temperature/humidity) “*” added to display when measurement exceeds 50.0 SPAD units
Repeatability Within ±0.3 SPAD units For SPAD value between 0.0 and 50.0 (with no change in sample position)
Reproducibility Within ±0.5 SPAD units
Temperature drift Within ±0.04 SPAD units/°C
Operating temperature/humidity range 0 to 50°C; Relative humidity of 85% or less (at 35°C) with no condensation
Storage temperature/humidity range -20 to 55°C; Relative humidity of 85% or less (at 35°C) with no condensation
Size; Weight 78(W)×164(H)×49(D)mm、200g(excluding batteries
Other Warning buzzer; User compensation factor
Standard accessories Depth stop; Strap; 2 AA-size alkaline batteries; Soft case; Reading checker

Specifications and appearance subject to change without notice.

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