1、 Purpose:

A portable chlorophyll meter can instantly measure the relative chlorophyll content or "greenness" of plant leaves, thereby understanding the true nitrate demand of plants and helping you understand the degree of soil nitrate deficiency or whether excessive nitrogen fertilizer has been applied. It is widely used in nitrogen fertilizer management, herbicide application, research on leaf aging, environmental stress, and other studies.

two、SPAD 502 Plus&SPAD502DL Plus chlorophyll analyzer

1. Principle: The SPAD 502 Plus&502DL Plus chlorophyll meter determines the relative amount of chlorophyll in a leaf by measuring its transmittance in two wavelength ranges (650nm and 940nm).

2. Composition:

üSPAD 502 Plus chlorophyll meter: measures the relative chlorophyll content or "greenness" of plants;

üSPAD 502DL Plus chlorophyll meter: measures the relative chlorophyll content or "greenness" of plantsBuilt in data acquisition unit（Data Logger）

üOptional:GPS/DGPS connection cableConnect the chlorophyll meter withCommunication cable between GPS/DGPS;

3characteristic

üReal time measurement of chlorophyll content or“Green degree”Measurement range-9.9 ~199.9 SPAD

üIn situ and non-destructive measurement

üTrend chart, save and display30 measurements——Latest features

üWaterproof design——Latest features

üfieldComparison between SPAD readings and university guided SPAD（www.specmeters.comProvided)

üstudies showSPAD measurement is highly correlated with leaf N content

üOptional with or without built-in data collection

SPAD 502DL PlusThe data collection unit

üCan be connected through serial portGPS connection

üBuilt in data collection andRS-232 communication

üStorable4096 measurements (1488 measurements with GPS added)

üCan be done throughFieldScout software sets up instruments and downloads data

ücompatibleSpecMaps online

4. Technical parameters

üMeasurement object: Plant leaves (mainly crop leaves)

üMeasurement principle: Two different wavelengths（The difference in optical density between 650nm and 940nm

üMeasurement area:2mm×3mm

üMaximum sample thickness:1.2mm

üSample insertion depth:12 mm (adjustable position to 0-6mm using depth adjustment device)

üLight source:2LED

üreceiver:1 SPD (silicon photodiode)

üMemory:30 sets of measurement data, capable of calculating/displaying the average value

üCan be stored when connected to a data collector4096 data points, when used in conjunction with GPS, can store 1488 data points

üPower supply:2AA alkaline battery (1.5V), capable of measuring over 20000 times

üMinimum measurement interval: approximately2 seconds

üAccuracy:± 1.0 SPAD units (0.0-50.0 SPAD units, at room temperature and humidity); When the SPAD exceeds 50.0 units, an "*" will be displayed

üRepeatability:Within ± 0.3 SPAD units (SPADbetweenBetween 0 and 50

üReproducibility:Within ± 0.5 SPAD units (SPAD)betweenBetween 0 and 50

üDisplay range:-9.9~199.9 SPAD units

üTemperature drift:Within ± 0.04 SPAD units/° C

üoperate temperature/Humidity range: 0-50 ° C, relative humidity within 85% (35 ° C), no condensation

üstorage temperature/Humidity range:- 20-55 ° C, relative humidity within 85% (35 ° C), no condensation

üOther: Warning sound, user coefficient compensation

üVolume (length)X Width x Height)：164×78×49mm

üWeight:SPAD 502 Plus：200g (excluding battery); SPAD 502DL Plus: 220g (without battery)

üStandard accessories:SPAD 502DL Plus： Depth slider, hand rope, software package, calibration card, RS-232data line

SPAD502 Plus： Depth slider, hand rope, 2 No. 5 batteries, inspection certificate, calibration card

5. Origin: United States/Japan