simple coir dust meter

Last few days I did some experiment regarding coir dust meters. At that time I could made this simple circuit diagram.Here I have used common Transistor Bc 547. Really this is a water sensitive circuit.We can use this circuit to measure whether coir dust is wet or dry.



How to operate:-

First of all switch on your multimeter and switch it to measure the voltage next get the handle and pull it in to the sack of coir dust ( That means A and B must go in to the sack) then read the meter.

Before stating to use this circuit get the value of dry coir and the wet coir then note down them. If a sack of coir get the nearest value you can send them to the factory to make crafts.

( If you like you can remove the LED)





Note:-

# Don't supply more than 4.5V
# Build this circuit on a PCB