SPAD 502 Plus Chlorophyll Meter:

The SPAD 502 Plus Chlorophyll Meter instantly measures chlorophyll content or “greenness” of your plants to reduce the risk of yield-limiting deficiencies or costly overfertilizing. The SPAD 502 Plus quantifies subtle changes or trends in plant health long before they’re visible to the human eye. Non-invasive measurement; simply clamp the meter over leafy tissue, and receive an indexed chlorophyll content reading (-9.9 to 199.9) in less than 2 seconds. Assess nitrogen needs by comparing in-field SPAD readings to university guidelines or to adequately fertilized reference strips. Research shows a strong correlation between SPAD measurements and leaf N content.

• Instantly measures chlorophyll content or “greenness” of your plants on a scale of -9.9 to 199.9
• Non-invasive, non-destructive measurement
• Trend graph stores and displays up to 30 measurements
• Waterproof design
• Compare in-field SPAD readings to university guidelines
• Research shows a strong correlation between SPAD measurements and leaf N content
• Available with or without a built-in data logger
• Includes hard carrying case and batteries

Data-logging model (2900PDL)

• Connects to any GPS receiver that has a serial output option*
• Equipped with internal data logger and RS-232 port
• Records 4,096 measurements (1,488 with added GPS/DGPS option)
• Configure and download meter with FieldScout® software and USB-to-3.5mm-Stereo-Plug Adapther (Item 3661U.(included)**
• Compatible with SpecConnect.

Specification:

Optical Density Difference at two wavelengths: 650 nm and 940 nm

Measurement Area: 2 mm x 3 mm  (Approximately 3/32 in x 1/8 in)

Light Source: 2 LEDs

Receptor: Silicon Photodiode

Power Source: 2 AA alkaline  batteries (1.5V)

Repeatability: Within ±0.3 SPAD unit

SPAD Value: Index of relative chlorophyll content; -9.9 to 199.9