Two Killed cRIOs? Help!

Pardon me if this isn’t the right place to post this but I have an urgent matter regarding our robot.

Well yesterday around mid-afternoon our robot was completed and handed off to the programming team (me and my assistants) to get it up and running. All is good and dandy right? Well we loaded our code, got everything in set and ran teleop. As expected everything worked. But only for about 10 seconds. Then we decided to run our shooter (two banebot’s 550 models hooked up to a 2.7:1 reduction CIM-U-LATOR), in which it spun up and then we lost connect to our cRIO. Upon further inspection our team discovered that our cRIO seemed to have fried. We didn’t know how this was possible but none the less not something that was impossible. We tried everything to get it back and running making sure that our wires were properly connecting, as well as using an external power supply in attempt to get it working. No luck. We replaced the cRIO with our spare, which is also slightly nonfunctional as the first cRIO slot doesn’t work, but can still run code.

After running the code and testing functions out on our robot for a good 5 minutes, the same thing happened as with our other one.

1.) We ran code for about 5 minutes, testing things to make sure our code and mechanical functions worked.
2.) After some use on the shooter we decided we’d test it one more time just to make sure everything was in check.
3.) Spinning the shooter up, we suddenly lose connection to the cRIO and everything on the bot shuts down and reboots.
4.) Upon inspection (once again) everything was fine except our cRIO, which happened to fry aswell. :eek:

We opened both cRIOs up to see if we could find anything wrong with them, or if we could spot any burnt marks but we could not.

Is there any advice to how to get these fixed or replaced? :confused:
And is there any reason that you guys might be able to come up with that could have caused this? And how to avoid it?

If you meant 775, it is very likely that your motors have shorts to the case and that your cRIO is not isolated properly from the frame. This causes current to or from the motor to flow through the cRIO and burns out the internal fuse. The fuse is not a user-replaceable part, contact NI for repairs.

No we don’t have any 775 bane bots on our robot. It was the 550. Sorry about that. Could they still cause the same thing though? Could you also describe where the internal fuse on the cRIO board if you know where it is so we can test it with a multi-meter to check if iin fact that it is blown?

I’m not aware of any case short issues with the 550 motors, but it is certainly possible. I don’t recall where on the board the fuse is.

Thanks. I’ll be sure to look more into it. We are pulling a huge amount of amperage though those 550’s, but I’m sure shorting is caused by more voltage rather than amperage. But they are also soldered questionably.

I would check the continuity between the 550 motor leads and the frame,
as well as between the power distributions board lugs and the frame. If anywhere is bellow 1M resistance you have a problem. It certainly sounds like a case short similar to the 775 motors from last year which killed a number of cRio’s (my teams included)

The fuse on the cRio circuit board is a large (1208?) white or yellow surface mount part right by the power connector on the front edge of the cRio, it should have a 2A, 5A, or 10A stamped on the top (i don’t remember the value). Given the description it is almost certainly the issue. I would not recommend replacing it yourself, contact NI and they will send you one immediately, they are very nice people to work with.

there is some good information in this post:

Thanks so much. I’ll be sure to shoot NI an email and call them Monday during our meeting. Yeah we’ve opened it up and thought that was the fuse. And it is labeled with “2A” (x’s being something that I can’t remember).

To reiterate: If you suspect the fuse, contact NI immediately. They will repair it very fast and get it back to you quickly - they understand what “Build Season” means.

We had the fuse blow 2 years ago, and they repaired it at no charge. Got it back in 2 days. :slight_smile:

I very strongly advise that you not attempt to repair it yourself.

Thanks Jet and Don. I’ve shot NI Customer Support an e-mail and will try calling them this Monday.

In the mean time I’m going to make our electrical team recheck all wires and soldering joints to ensure they are properly taken care of.

Having two units fail like that in rapid succession certainly sounds like some sort of electrical fault due to improper isolation. Please verify your chassis is properly isolated from the frame.

on a semi related note, i like how you can accidentally hook up the robot power backwards and it doesn’t get damaged, but the rest of the electronics do. (rushed re-wiring after finding grounding “problem” caused by cims being used)