This AC-CDI is EOL Consider New ACCDI v11 instead !
- Programmable AC-CDI
- For ONE or TWO* cylinders
For [2 strokes engines] and for [4 strokes engines with wasted spark*]
* On 4stk engines with 1 pickup on the crankshaft, one spark occur at compression stroke and one at exhaust stroke. Firing in the exhaust stroke is a wasted spark. Hence the name…
- 80MHz MicroController control unit
- Easy programming with Micro USB Type B connection and terminal console
- Compatible Windows, Linux, Mac, (some Android)
- One customizable ignition timing curve
- Rev from 10 to 30,000 RPM
- 0 deg advance from 1 to 500 RPM (to avoid kickback)
- Adjustable timing in 13 steps from 500 to 20,000RPM
- Soft rev limiter.
- Temporary Legal rev limiter.
- Stator can be half or full rectified (for more power and ground isolation).
- 1 input for an inductive pickup (VR) or Hall type or Points
- Pickup polarity can be set to Positive, Negative or Automatic detection.
- 1 output for a Capacitive coil type.
- Non volatile configuration
- 12v Tachometer output (Even 12v)
- Kill switch input
- Charging voltage can be 100 to 600Vac
- Power supply voltage DC 10 to 16 volts
- Current drain: 100mA
- Protected against reverse supply voltage
- Available as a ready-to-use device in the SHOP section
- Dimensions: 100 x 60 x 25mm (3.9 x 2.4 x 1inch)
- Plastic box potted for Electrical insulation, Protecting components from mechanical shock and vibration, thermal shock or Moisture
- 15cm(6”) 1.5mm2(16AWG) wires soldered with 6.3mm automotive female connector
- Source not available
- Made in France
* Twin-cylinders at 360° crankshaft angle:
The engine works with WASTED spark.
If there is ONE twin coil:
=> This AC-CDI works.
See: CDI compatibility
Remember that ignition coils are different from TCI to CDI system
– CDI coils have low inductance and impedance around 0.5-0.8ohm
– TCI coils have higher inductance and impedance around 1-3ohm
Remember there are AC-CDI and DC-CDI…
A pickup (aka: VR, Variable Reluctor, Reluctor) is a sensor that have a signal wires and a ground wire.
It’s made of a coil of wire wrapped around a magnet. When a ferrous part passes by the magnet, the magnetic field is modified and a voltage pulse is created in the coil generating a sine wave.
– 1 input for inductive pickup with 1 signal per crank rev.
– Pickup must puts out 3 to 30Vac
– Points, reluctors, Hall sensor, optical sensors can be used as long as they give only 1 pulse per revolution.
– 3 wires digital Hall effect sensors need an external pullup resistor. The default voltage output is equal to Vcc (+5v to 24v). When a magnet passes in front of the sensor, the output voltage goes low and the ignition will detect the RISING edge meaning the trigger moment will be when the magnet LEAVE the sensor.
– This CDI works with 1 pickup and 1 reluctor (the metal strip on the flywheel) [A,B].
– This CDI works with 2 pickup and 2 bars [E,F].
– This CDI DOES NOT work with 1 pickup and multi-pulses pickup (ie 2 reluctors on flywheel) [C,D].
– This CDI DOES NOT work with 1 pickup and missing tooth flywheel [G].
Even if it seems instantaneous, the flame front take some time to expand and ignite all the air+fuel mixture in the combustion chamber.
It becomes critical at high rpm. That’s why the ignition box should fire the spark a few degrees before the piston reaches Top Dead Center so the mixture explode just when the piston begin to back up. Generally engines need to be ignited around 30 to 40° BTDC (Before Top Dead Center)
It’s the ignition box job to calculate the timing according to the RPM. It makes the calculation as soon as it detect a pickup signal.
Therefore if the box need to ignite the engine 40° BTDC, the pickup signal MUST trigger the box BEFORE 40° BTDC.
So the pickup position can be 42° BTDC but also anywhere else!
Due to mechanical constraint, manufacturers put the pickup at different position, Yam XT600 was 36° btdc, Honda often uses 72° and so on.
As the ignition box has been triggered way before it needs to fire the engine, the box just wait until it’s time to fire.
How to calculate the Pickup Position?
Check the polarity of the pickup (Negative then Positive/NP or the opposite PN) with a Needle galvanometer (in milliAmp position) while kicking.
For a better understanding, this video can help.
The last RPM value you enter is the “rev limit” that stop all sparks.
Legal Rev Limiter:
If you turn On then Off the KILL switch during the first 30 seconds after the engine started, a Temporary Rev Limiter will allow 3500RPM maximum for the current run.
After 30 seconds, Kill switch acts normally and stop the CDI.
After the bike has been stopped and restarted by the Master Ignition Key, the CDI runs without restriction.
In countries where 50cc are strictly restricted, the bike seems legal in case of control…
It can also be handy if a beginner rider tries the bike.
Terminal consoleClick here for more info
– Use a Terminal Software as CoolTerm or Teraterm or Putty or Kitty .
– Use Serial USB Terminal by Kai Morich and a Male-Male USB type-C OTG connector to USB micro-B. (video)
The phone must be OTG compatible with OTG turned on:
settings——additional settings—–enable/disable OTG.
– Shell commands:
screen /dev/cn.usbserial-xxxxxxxx 115200 -L
screen /dev/tty.usbserial-xxxxxxxx 115200
– Use a Terminal Software as CoolTerm or Putty.
– Use Shell commands to find the COM-port:
tail -f /var/log/syslog | grep USB
dmesg | egrep --color 'serial|ttyS'
stty -a </dev/ttyUSB0
stty -F /dev/ttyUSB0 cs8 115200 time 10
Connection to the device:
cat /dev/ttyUSB0 & cat > /dev/ttyUSB0
PHOTOS.Click here for more photos
Setup with Android app:
MBX 125 onboard with programmable CDI:
Connection to the box:
Setup a ignition timing:
Change the ignition timing:
Test of an ACCDIv10:
ACCDIv10 powered by AC2DCCDI (DC converter)
VERSIONSClick here for more info
- Version v10r0c0:
- First Version.
- 5 seconds temporization to detect console.
- Wires come out at 90degrees.
- LED on the length side.
- Version v10r1c0:
- Automatic detection of the console.
- Wires come out at 180degrees.
- Stator can be half or full rectified.
- Version v10r2c0:
- Square +12v Tachometer output.