looking for some help on choosing a base resistor for a transistor!
transistor is a ZTX300 (was the only one i could find lying around.) Im trying to run a relay from my arduino,its rated voltage is 24V and coil current is 30mA.
Ive done numerous calcs and came up with different resistor values!! Heres the one im semi confident on! Please let me know id i done it wrong
Data sheet links
formula Rb = Vc*hfe / 5*lc my calcs (24*50)= 1200/(5*.03)=8000
So going by this am i correct in assuming i need an 8K resistor?
If not,does anyone know what resistor i need because my head hurts and i give up