NPK sensor can be used to determine soil fertility by measuring Nitroger,Phosphorous & Potassium content of the soil and decide on the required fertilizers to use.
It has 3 pins Stainless Steel Probe which is IP68 rating protected against rust,salt,alkaline.
RS485 communication protocol is used to enable long distance data transmit.
RS485 -TTL converter is required to use with Arduino.
MAX485 converters available in market have some voltage level issues and will not work with NPK.
We need to use MAX13487 auto direction enabled converter for effective data transfer.
buy link & code download :
https://www.alselectro.in/product-page/soil-npk-sensor
