Power Distribution Board.

[AndyTham]

Hi, does anyone have any information regarding the internal workings of the First Diversified Systems power distribution board? Recently while making a huge mistake of working on a live circuit, has unfortunately resulted in shorting out the power distribution board. We have ran various tests on the board to determine the problem, most of the board seems to be working fine. But, the major issue is where the C-rio obtains power. We are only able to get 12.5V, only half of the 24V need to power up the C-rio. Has this ever happened to anyone? Please reply with your thoughts and ides, all help is strongly appreciated. Thank you.

[MagiChau]

The manual is on the FIRST website.
http://usfirst.org/uploadedFiles/Rob...tion_Board.pdf

http://usfirst.org/roboticsprograms/....aspx?id=18530
List of guides regarding parts, and other things related to FRC.

[ebarker]

There is an active circuit in the item that converts 12VDC to 24VDC. You probably let the smoke out.

I think the new smoke cost about $ 189 from AndyMark. About the same cost as a college textbook. You can write off the expense to a life experience 'tuition. I wouldn't waste time working with the board.

Working with electricity and machines can be hazardous to both machine and man. If you can get some procedures in place for working on machines then both man and machine will be safer. At least no one got hurt, just some feelings.

[AndyTham]

"ZonChau", on behalf of team 2625 we thank you kindly for your reply. But, I have already looked through these manuals and kit of parts data sheets through the USFirst website. Unfortunately, they provide very limited information of why there is reduced power to the C-rio port. I believe it may be a fault in the step up inverter circuit, but it seems to be impossible to trace connections on these dual layered surface mount PCB's. If it is possible could anyone provide schematics to the power distribution board. Your help is strongly appreciated!

[AndyTham]

'Ebarker', thank you your your reply. It is fully understood that it may be hazardous on the machine and man to be servicing these board. But, $189 is very, very pricey, considering the other major expenses that must be made towards other components. We have had the identical issue with another board in Breakaway 2010, therefore resulting in 2 blown boards. We have a brand new board from the 2011 kit of parts to use, so we are safe. But, I would like to have this board repaired to use as a spare. As we all know, I tend to blow them a lot!

[ebarker]

Now you really have perked up my interest. Exactly what does one do to blow up this board ? Twice ? I'll make sure we never do that.

Way way back in my day I blew up enough electronics and got shocked enough to learn to never do that again.

I'm just wondering how y'all blew up the converters.

[AndyTham]

Attn: Ebarker, I'm glad that I have interested you in my electrical issues. Hopefully I will find someone who can help me resolve this issue. I honestly have no idea how it blew. I had powered it up to run the C-rio for the programmers to mess with 'IP'. And, suddenly the C-rio had turned off. Scared to death that I may have blew the $3000 C-rio, so I quickly found the issue that we were getting no power from the 24VDC port. After I had made various attempts to resolve this issue, and had replaced a diode that is right before the output. Which allowed me to obtain a steady 12VDC, but is still not enough to power up the C-rio. I have came to a conclusion that there may be a number of parts that could have burned further up in the step-up inverter circuit. The second board basically burned out the same way, but is damaged beyond repair.

[Joe Ross]

Originally Posted by AndyTham

"ZonChau", on behalf of team 2625 we thank you kindly for your reply. But, I have already looked through these manuals and kit of parts data sheets through the USFirst website. Unfortunately, they provide very limited information of why there is reduced power to the C-rio port. I believe it may be a fault in the step up inverter circuit, but it seems to be impossible to trace connections on these dual layered surface mount PCB's. If it is possible could anyone provide schematics to the power distribution board. Your help is strongly appreciated!

Go back to ZonChau's link, and click on "Design Packages for Control System and Sensor Boards"

[AndyTham]

'Joe Ross', on behalf of team #2625, we would like to thank you for kindly replying. This is information that is incredible, and will help me find a solution to repairing the PD board. I will make a further investigation of the schematics provided to resolve the issue. Your help is very much appreciated, and was very useful to our team!

[MarkoRamius1086]

If I may add something, I know a big rookie mistake (we all make) is drill and file other pieces of the robot around the electrical board. These resulting bits and filings of metal and plastics can float around and find their way into the small crevices of the wiring inputs for all of the electronics

I have seen (and smelled ) more electronics burned at Regional and local offseason competitions than I wish to elaborate about. If you are a team making last minute changes right ontop of your final robot (we all do that at one point or another) without putting some kind of bag or block over the electronics package (something I highly encourage), expect something like your cRIO, PDB, Victors, and Jags to F-R-Y: Fry!

Best of luck this season!
Petrie

[AndyTham]

"Marko", This is definitely a huge rookie mistake. For the last year that I have been with team #2625 I have learned to realize that drilling or filing aluminum over the electronics, are bound to short out the controls. We have burned 2 PD boards, 3 jaguars! It's a mistake that we all make, but its also something that we should all learn from, and make our best efforts to spread the word and prevent from making such mistakes. Our team is working towards drastic measures to prevent the re-occurrence of such mistakes. Thank you for your reply, I'm sure that many others will learn from this as much as I did. It was very much appreciated.

[SuperBK]

Even veteran teams get a new PD board each year. Maybe somebody has a spare they will sell you.

[AndyTham]

@SuperBK, Thank you for your reply. It may be a possibility that there is a veteran team out there that is willing to sell us an extra board. Hopefully We can pick one up for a very cheap price!

[EricVanWyk]

When you do find the exact cause, could you please report it back to me? I designed the PD, and we are always looking to make it more robust.

If it is metal shavings, there isn't really a whole lot more to be done beyond the conformal coat.

EDIT: What does your signature mean? V-Dub was my nickname a few years back...

[Sammy 3278]

I realize I am over a year late but the schematics for all the FRC control system circuit boards including the PD board can be found here.
http://www.usfirst.org/roboticsprogr...stem-resources