Miller Boost Circuit Board Assembly NO. 200841

Hi Alex,

Reverse engineering a board of this size and complexity is a monumental task. Congratulations on what you have accomplished. Sorry I don't have the information you are looking for but your work caught my attentions and I wanted to say I hope you get the reading you need and I hope it all works out.

John

Josh,

First of thank you for your reply.

Is to easy to reverse engineering this board, however, it is time consuming a speacially when team of one working on entire project.

I'm planing some changes for Rev 2.0 of this board, such as an absolite unshielded inductor L1, VR4 LDO that converts +30V to +15V and getting HOT under formal coating without heatsink by manufacturer, adding fuses.

After reviewing design i came to conclusion! When VR4 fails under heat it damages boost board that cost $2000 dollars and also damages the main board that cost $1600.

None of these boards has ANY fuses!

In any case, if i could get Ohm value between pins 2 and 3 on R86 it will really help.

R86 has 3 pins and it is a verablabe resistor.

pins 1&2 are shorted together by design and pins 2-3 has Ohm /K Ohm value between 0 to 10K

Hi Alex,

I just saw your post and am troubleshooting a Dynasty 200SD as well.   My board is showing 0.430 ohms between pins 2 and 3 on R86.  I found my first problem was a burnt connection on the input relay (PC2, main board back left corner).  What voltage do you get on pins 7 and 8 for RC1 when you measure against the ground plane (pin 3)?  My tech manual says I should get +15V on pin 7 and -15V on pin 8, but I am only seeing exactly -12V on pin 8.  If it were a random voltage other than exactly -12V, I would suspect a bad zener or reference voltage for the controller, but it just seems like exactly -12V  is  too coincidental. Would you be willing to share the schematic?

Jon

Hello Alex,

can you tell me what the component is next to the large 5uf capacitor in your photo, it is labeled US1.

this would be on the dynasty 200 power interconnect board.

thanks so much.

Thomas

Hi Alex,

I had this board.

Still You need value between pins 2 and 3 on R86?

This thread is looking a bit dated. I wonder if there is any further progress on this?

Frankly if someone has the values, and the answer hasn't been publicly posted, then go straight to publicly posting the answer for anyone else that finds this rather than asking if they still need it.

Thanks!

The value of R86 as it says in the technical manual adjusts the limit for the line current, by default it is approximately 10 ohms. R86 makes a voltage divider with R99 adjusted from 0 to 7.5V approximately, it is compared with the current of the HD1 transducer of 6.25A per volt. For example if you want to limit it to 43 amp, you would have to adjust the voltage divider R86 and R99 to 7Volts.

Hello friend, I congratulate you on the tremendous task of doing reverse engineering to a printed circuit.

I bought a bad Dynasty 200 machine in a mess.

When I opened it, I found faults in the 200841 card where it has the Q3 transistor exploded, the resistance R7 charred and C5 as well.

The transistor is a 2N3304 (I don't know if it's PNP or NPN), the C5 seems to be 1 nano Farad / 400V.

Also the 207818H board has the R6 burst / charred resistor and the IGBT Q11 (G4PH50UD) shorted.

If you could help me with the values of the resistors it would be great.

Here there are many who have the original service manual with the circuit diagram but nobody helps you, finally buy it for a specific case like this but not even that. !!

Anyway, I hope you can help me please.

Wouldn't it be better if you shared the manual for a price?

Greetings.