Introduction

The CDI (Capacitive Discharge Ignition) there is the electronic heart of the XL600. It controls the ignition of the engine.The two XL600 drivers Frosch and Thomas took the initiative to come, to the mystery of the black box a little closer. Thomas made ??a few measurements on the CDI with its XL600 with PD03. Frosch dissected a CDI of PD04. Both have been documented in the picture. Finally, I got (Olli2) the components of the CDI and tried the circuit and component analysis of. The principle of the ignition timing is provided thanks to Dieter's research and Thomas' description.

General function of the CDIFor the XL600 Honda developed by three different versions of the CDI:

PD03 (Rd):round connector with 6 pinsMarked "MG2 CF447"Honda Code: 30 401-MG2-871Ignition data, according to Honda workshop manual:Ignition Timing: 6° before TDC in 1300 rpm

31° before TDC in 4000 rpm

PD03 (Rf):two rectangular connector with 4 pins and 2Marked "MG2 CF476A"Honda Code: 30 410-MG2-891Ignition data, according to Honda workshop manual:Ignition Timing: 11° before TDC in 1300 rpm

31° before TDC in 3500 rpm

Further labeling of CDIs for the PD03 models (Fiche-Recherche):30 401-MG3-003: RD, LD all countries except Austria and Switzerland30 401-MG2-871: Rd only Switzerland and Austria30 401-MG2-891: Rf all countries30 401-MG2-892: R g, h any country

PD04 (all models):two rectangular connector with 4 pins and 2Marked "MK5 CI-87"Honda Code: 30 410-MK5-003Ignition data, according to Honda workshop manual:Ignition Timing: 8° before TDC at 1300 rpm

28° before TDC at 4000 rpm

Size comparison, on the left PD04, on the right PD03.There is a presumption that the PD04 CDI is therefore greater, because in her a spark timing adjustment there is realized in event of legacy engine.In the PD04 CDI there is a pin with a magnetic switch (+) connected, in the PD03 CDI it is connected to the pulse generator mass.

Connections of the PD03 CDIs

All CDIs have 6 - and 2 +4 - pin connectors with these connections:

Wire color Connection Designation in the schematic

XL600

Green G Ground Ground PD03/PD04Black / Red BL / R Alternator charging coil PD03/PD04Black / White Bl / W ignition engine stop PD03/PD04Black / Yellow Bl / Y Ignition Coil Ignition Coil PD03/PD04Blue / Yellow f / Y Pulse Pulse Generator PD03/PD04Green / White G / Y Pulse Pulse Generator PD03Yellow / Red Y / R Start Starter Switch PD04

Ignition at 1350 rpm Ignition at 4200 rpm

Charge coil: violetPulse generator: yellowIgnition coil: light blue

The design of XL's ignition is implemented such that for each revolution of the crankshaft the spark is triggered. It is to ignite the mixture but would be required only on every second revolution.

The speed of the motor and thus its frequency (FM) is marked by the two cursors (vertical dashed lines). Its numerical value is specified with the variable 1/ÄX.

F_M = 1350rpm / 60s = 22,5rps = 22,5Hz F_M = 4200rpm / 60s = 70,0rps = 70,0Hz

CDI = Capacitive Discharge Ignition, i.e. The ignition is triggered by the discharge of a capacitor. Consequently, the capacitor must be charged first. This is done by Charging coil (ignition coil, alternator) of the generator, black / red wire to the CDI.

It is easy to see that six pulses represent the typical Charging curve (envelope) of the capacitor (purple). The ignition pulse (light blue) is raised before the pulse (yellow) supplies its signal at top dead center (TDC) of the CDI. Although the two representations are not in scale with each other, so it is seen that the ignition advance depending on the rotational speed, two different values, times, and thus we can assume angle.

The difference between the trigger pulse (Zi) for the pulse generator (IG) is the angle of ignition timing (Fz). Roughly estimated it in the image of the lower speed about 2% in view of the higher speed about 9%. This corresponds to about 7.2 ° and 32.4 ° spark advance. This is consistent with the indication of CDIs for the XL600Rd.

I had to print the pictures and then measured with a ruler the distanceand a calculated a ratio. For example:Zi -> Ig = 1mmZi -> Zi = 111mm = 360° = 100%1 mm / 111 mm = 0.09 = 9%9% x 360° = 32.4°

This is of course correspondingly imprecise, there are measuring and reading errors.In addition, the division of the stress axis is not known and therefore the trigger threshold of the pulse signal is not exactly as determined.

On the charging capacitor Dieter was able to measure using a Digitaloszilloscops voltage values ??on the order of 210-240V.

Analysis of the CDI of a XL600 PD04

Components, parts list

Component Label measured UAK (mV)Diode 0 DIV64 520Diode 1 DIV64 520Diode 2 DIV64 520Diode 3 DIV64 520Diode 4 NB6406 410Diode 5 546Diode 6 643Diode 7 550Diode 8 550Diode 9 557

Component Label measured UKA (mV)Z-Diode 1 7V5Z-Diode 2 7V5Z-Diode 3 5V

Component Label measured C (F)C0 2,218μC1 1,468μC2 15,9nC3 Elko 10μ/50V 9,7μC4 Elko 10μ/50V 9,9μC5 153k (15n) 15,8nC6 Elko 47μ/10V 50,2μC7 Elko 10μ/16V 11,2μC8 222k (2,2n) 2,35nC9 ? (evtl. 47nF)C10 ? (evtl. 100nF)C11 150n 154,2nC12 153k (15n) 15,2nC13 473k (47n) 47,4nC14 153k (15n) 15,4nC15 153k (15n) 16,2nC16 Elko 10μ/50V 10,1μC17 153k (15n) 14,6nC18 153k (15n) 15,2n

Component Label (Color Code) measured R (Ω)R1 20k 20k1R2 1k 999RR3 15k 14k97R4 10k 10k08R5 510R 510RR6 154k 176k5R7 390k 398kR8 1k 1kR9 56k 56k6R10 174k 179k2R11 12R 11R5R12 nb nbR13 1k5 1k509R14 2k9 2k44R15 56k 56k2R16 56k 56k5R17 249k 235kR18 10k 10k22R19 510R 508RR20 2k9 2k42R21 2k9 2k45R22 10k 10k18R23 10k 10kR24 1k 1kRx1 28k 27k3Rx2 42k 42k7

Component IC typeThQ1 (2S)A1015 Y61 PNPQ2 C944 SK5Y NPNQ3 2204 6JQ4 (2S)A1015 Y61 PNPQ5 12045HQ6 12046HQ7 (2S)A1015 Y61 PNPSCR NEC 2P4MP 67 data sheetBuffer TC4049BP data sheetIgnition Control FM4213, MR4213 data sheetIC custom made ? ?

Wiring diagram

Special features

The wiring diagram and the part list helped for the analysis of the PCB and the components. The application in the data sheet has been additionally helpful.

The Charging coil (alternator) supplies power to the CDI. The diodes D0 and D3 form a simple rectifier, if the capacitor C0 is a voltage buffer.

At the same time invites the Charging coil (alternator) through the diode D0 the capacitor C1 to the positive half-cycle the ignition on.

The pulse generator is clocked through transistors Q1 and Q2 to the IC1 (Ignition Control Circuit, if ICC) on pins 2 and 7. The information of the speed and the time of the TDC are included here in it. The ignition is then triggered depending on the rotational speed. This is done by controlling the thyristor SCR, if it is conducting or not. The thyristor is conductive as long as the capacitor charge is discharged.

The charge capacitor C1 will discharge its energy through the primary winding of the ignition coil connected externally. This in turn transform the tension further up, such that the electric spark at the spark plug can skip to the mixture ignited.

The ignition timing can have two or three different values for the advance:

• Example: 28° advanceThe speed-dependent evaluation is most likely realized by the wiring of the combinations of resistors and capacitors on pins 11-14 of the ICC. The output pin 10 then controls the transistor Q4 to the thyristor SCR.

• Example: 8° advanceAt low engine speeds, the control pin 11 of the ICC over the Converter Stage 3 of IC2 the transistor Q3, which is over the stage 1 that controls, the transistors Q5 and Q4. The latter served again the thyristor.

• Example spark advance in electric start:

In this case, the motor turns very slowly and the spark advance is expected to adopt an even lower angle. The signal of the pulse generator (pulse generator) is provided on Q2 not only to the ICC Pin 7, but also to the IC2 pin 9 The signal is out of the converter stages 4 and 5 of IC2 and is applied to pin 12.

The combination of C14 and R16 is probably the suppression of low frequency and DC voltage levels. On the converter stages 6 and 2 of the transistor 6 is controlled. Together with the transistor 7, which is is replaced by the e-start its control, the thyristor returns to the conducting state.

The black / white wire is connected to the kill switch, engine stop. It is in operation to ground, the power to the CDI is therefore no longer guaranteed and the ignition is stopped immediately.

Block diagram of the CDI and the ignition components:

Where:1. charge coil2. Pulse3. and4. Signal generator (see function diagram)5. "Comparator"6. Processing unit for trigger pulse to SCR 97. Before ignition computation8. Diode for rectifying the charging voltage of the capacitor9. Thyristor10. CDI Case11. Capacitor12. Spark plug13. Ignition coil

Note: the scheme is highly simplified and represents only are the main functions of the CDI

Signal of the pulse generator

1. Pulse generator cam2. Pickup coil

When approaching the coil of the first cam induces a positive voltage pulse (A)The zero crossing of the pulse occurs when the cam and the coil face exactly (B)Then changes the direction of the magnetic field and thus the direction of the induced voltage (C)

Scheme of the ignition timing

The calculation of the CDI is based on the comparison of two voltage ramps (2 +3 in the diagram 3).While the ramp 2 always takes the same course, the steepness of the ramp 3 from the CDI is changed with engine speed (N1 low speed ... N4 high speed, maximum ignition timing 31 °).In the "comparator" (5 in Figure 1), both of these voltages are with each other compared.When the voltage 2 the value of the voltage 3, the ignition (represented by T1 ... T4 is triggered at point 5).The ignition timing is shown in the diagram at point 4 by the intersection of the two voltage ramps.This is also clear that the mere height of the pulse from the pulse generator has no influence on the ignition timing, as this is calculated purely from the generated voltage ramps within the CDI.

Olli2, March 2005, Olli2@XL600.de