I'm building a vehicle powered veggy oil run controller. Doesn't start using veggy oil (pull veggy solenoid) until warmed up and, when running on veggy, doesn't shutoff engine with ignition going off (you take keys out and lock car, it switches back to diesel and runs on (to purge fuel lines and injector pump - so it do will start cold). ((Up and running on jumper battery now - ready to connect to vehicle power.)) First problem is voltage surges. Need simple choke, zener diode, and cap. circuit (?) to go along with arduino regulator. Don't know cap and chokes but figuring charge at 14v and arduino OK at 8.2v (regulation fails at 6v) - the zener and resistor for a 100mA (50mA for it and 50 for two relays) to the "vin" supply, the circuit should be:
___-----(R1)------------------>
___+14v_______I_______+8.2v
______________I
Battery_______(Z1)______Arduino
______________I
______________I
___---------------------------->
Gnd
with:
Z1 zener diode at 8.2v and 700 mW (use 2 watts for surges)
R1 resistor at 70 ohms and 2 watts
and to protect arduino:
2x capacitors?
2x chokes?
Correct?