I am a hobbyst, and recently been working on a small project of my own, Creating a rev limiter of my own.
First of all following part of the ckt is original: +12v,To Vehicle's Trigger,spark plug;Transformer/Ignition Coil
Rest is DIY
There have been few problems I've encoutered and need help with :
- As soon as I connect the collector @ c and emmitter to GND(Vehicle's battery -ve terminal), the engine halts(or bike won't start), ( even when the gate is pulled down )
--> Multimeter Probe Red on Ground and Black on E ( while DIY ckt is not grounded ) showed a +0.18 volts ie: ground is positive while E is negative !!! WHY ??
--> I figured out that when I dissconect 1N5408, and the ckt when connected to GND and @ C to primary side of ignition coil It won't halt the bike but also then the gate won't open (applying 12 volts from battery +ve)
ie: Closed gate works fine but open gate won't shut the bike off, ie: the gate won't open !?
- I've read about inductive loads, as soon as vehicle's trigger switch opens there will be oppossing voltage ie: highly +ve @ C (hence 4.7uf capacitor acts as IGBT protector while .1uf cap prevents accidental gate opening since gate-collector absorb some charge on their own (same with gate-emmiter)) so the current shall flow from C to E, but because of diode I noticed current is flowing oppossite, hence the bike is halting even when the gate is closed.
"Ignition Coil socket" when dissconnected and (socket being measured) measured using voltmeter shows +ve and -ve(black wire) as shown in picture.
Only 2 wires @ ignition coil primary side socket, so I figured out the trigger is integrated with ECU.
Also the Ignition coil measured 2-2.5 ohms.
Ignition Cut diy is a signal, for testing purpose I am using +12 volts from battery's +ve terminal
IGBT is 25N120A
Also, I've tried the above ckt with inductive load (Toy Car Motor) works just fine.