Blown up electrical board
 

We are having a problem with our control system. When we try to get feed from the camera, the robot goes into watchdog mode. this started happening 3-4 days ago. prior to that, everything was working perfectly. the camera would track and follow and shoot and all that. but now as soon as we enable the robot, it goes into watchdog mode because the camera does not get any information to send to the cRio. the camera light on the cRio is solid orange (even tho it should be flashing to show data transfer). then we called NI and they said we might have reset the password. so we did that and then we went to test it on our practice robot but the cRio does not turn on. when we remove the WAGO connector from the cRio side to measure voltage, we get 24.5V, but when we plug it back into the cRio, we get 3.27V. we tried it with many batteries. we tried using 3 different power distribution board. but no luck. So then we called NI again, and they said lots of teams have the same problem and that they will send us another cRio overnight. we are still waiting for the new one to arrive but would like your feed back on what might be wrong. we also tried using the old backup code from 2 weeks ago which we knew worked for sure!
we look forward to your opinion.

Re: Blown up electrical board
 

Unfortunately you got some incorrect information as we have not seen other teams reporting the behavior you are seeing (24V drops to 3V when connected to cRIO). This appears to be a new and strange issue, so please send in your current controller ASAP so we can take a look.

+Chris

Re: Blown up electrical board
 

Thanks for the quick reply, and we are recieving a replacment cRio, but my question now is how do we send our damaged cRio in for inspection?

Re: Blown up electrical board
 

Your contact should receive an email from NI with instructions once the replacement is on its way.

Re: Blown up electrical board
 

Please don't use such sensationalist headlines, you gave me half a heart attack.

When the cRIO supply is at 3V, what does the battery read as? Are any other systems still powered? What do the DSC power indication LEDs say?

Re: Blown up electrical board
 

As I described on this identical thread on the FIRST Control System forum, I'm suspicious about the isolation of your chassis. I wonder if you've got a live chassis (probably due to the camera's live chassis) and you're getting some tricky "ground loop-like" issues.

Please confirm that your chassis is isolated and that the cRIO's frame and camera's frame aren't "touching" something else.

Russ

Re: Blown up electrical board
 

when the cRio power was at 3V, the battery was at 13.05V or something...
our camera wasnt plugged in at that time so i dont think the camera isolation was the problem.
and we did this testing when the cRio was off the robot (since we had to ship it), and it was on a wooden table so i guess that eliminates that possibility also.

so we finally reset the password on the camera again today and the good news is, EVERYTHING WORKS AGAIN!!! (even the not working 3.0V cRio works)
we just left it in a drawer over night, and it fixed itself :confused: ...

my thinking is that we still send in our cRio to NI once we receive our replacement one just to make sure that this does not happen in competition again.

thanks for the help guys

edit. oh and btw the reason i used such sensationalist headlines is to get attention so more people read it and try to help :P thats all

Re: Blown up electrical board
 

I would go ahead and double check your cRio power cable as well. Shorting the power supply may cause it drop out, and a free wire could short one day and be fixed the next. Make sure that you don't have any exposed wire near the connectors.

Re: Blown up electrical board
 

yea, one of the posts said that we could damage the cRio if the wires are not properly connected in the WAGO connector. we took them out and re-connected them on both ends. i hope it does not happen again because it would be sad to have a really good robot but not be able to use it because of a loose wire.

Re: Blown up electrical board
 

If you're up and running, you can go ahead and cancel the RMA request :)

Re: Blown up electrical board
 

yes we will once we finish our testing properly. i know the cRios are expensive.
today we just finished wiring up our practice robot and we turned it on and it worked surprisingly. we tested camera "feed" and it worked. we havent done any other tests yet.

Re: Blown up electrical board
 

No one has mentioned this... What about your power distribution board? I know it's outputting the correct voltage at no load, but it shouldn't be going down to 3V.

How much current is being pulled by the cRIO when you try to run it.

I'm trying to find the power requirements for the cRIO...

EDIT:
A = W / V

So 20W at 24V = 20W/24V = 10W/12V = 5W/6V = .83A Max

So if you measure the current from the Power Distribution Board to the cRIO, it should not go past .83A. If it does, then it's the cRIO, if not, it's the PDB.

Re: Blown up electrical board
 

Also the 24V supply on the PD is fused. Dropping to 3V is very unusual, and is more of an indication of starvation on the 12V side.

Re: Blown up electrical board
 

Note that that problem was solved by reseating the cRIO power wires, a poor connection here makes perfect sense for the symptoms described.

You would get ~24V with no load, but as soon as the cRIO is plugged in the voltage would plummet as current is pulled through the high impedance connection.

Re: Blown up electrical board
 

What post said that? I'd like to know which connector it was talking about.