Gyro Smoking

We opened up the Basic Main code and ran it on the cRIO and less than 30 seconds later, the gyro burst into smoke.

It is extremely hot to the touch and the chip fell off of the circuit board. Our electrical guys have no idea why this happened and we can’t give them a logical answer besides it was plugged in wrong which they say it wasn’t. Any ideas?

We have used this same gyro in past years and it has worked without problem

Could you take a photo of it so we can see the wiring?

Also, I like software that can set the world afire…::safety::

here you go.

Sorry about the bad quality, the only member with a camera is currently getting food so we had to use a phone camera.

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0119001621.jpg

Well that’s not what it is supposed to do!

I haven’t heard of any of the other 2009 Gyro’s having thermal events, so I’d love to hear more details. Perhaps you some how got the power reversed?

Fortunately, you should have another one in the 2010 KoP.

The other end of that wire is just as important as the end pictured for determining if it was wired correctly

that’s what the electronics guys gave me. We took it off the bot and I think we threw it away. The 2010 gyro seems to be working, but we always have hands on the E-Stop button just in case.

EDIT: Check that, we still have the gyro, I’ll see if I can’t get a picture for you

Just a thought…The mounting holes for the board are part of the ground plane so if you have an electrical problem on the frame, you may have run a lot of current through the board. Double check your other robot wiring before you hook up the second device. The Crio chassis is also tied to the negative terminal of the battery and needs to be isolated from the frame.

Good call, Al. Shorting the Gyro’s ground to the frame could easily create this problem.

There is a small gap between the mounting holes and the ground plane, but it could easily be bridged by e.g. using a metal standoff/nut that is too big or too tight. Or, it could be bridged by mounting it too close to the frame, and having one of the soldered leads hitting the frame.

The book says to mount it with plastic hardware. The short could certainly do it. I saw one post where they had hooked their gyro to a PWM output. That could do it too.

I just tried our KOP Gyro (fresh out of the bag).

Ours also got hot as soon as I plugged it in.

As an experienced electronics guy, my nose is sensitive to “hot” smells, so I caught it pretty soon.

I checked the wiring at both ends, and went back to the online docs.

No clear reason for the heat. (Wiring looks clean & polarity was correct.)

I tried it again (double verifying plug polarity) and it still gets hot (almost too hot to touch)

Doesn’t seem right. So I went looking, and found this thread.
Ours wasn’t mounted at first, so it’s not a chassis short.

Anyone else have ideas?

i would check to see if there are any vents on it that are blocked and if there aren’t any vents i would take off the casing(if possible) and cut a couple of slts for vents(if possible if not a cooling fan could do also)

I don’t mean to be rude but this makes absolutely no sense.

Check out the picture earlier in this thread to see what component is being discussed.

Phil,
The only thing to check for is imperfectly etched boards. There may be a few traces that are close together that didn’t get fully etched. Also possible that you have a solder bridge. Does anybody remember whether these devices are static sensitive?

If you’re like me, you have trouble even seeing the traces on these boards…
I’ll get out my Dino-Scope today to check on the boards…

Problem like this really kill the schedule :frowning:

Hey,
I don’t have trouble seeing, there just isn’t enough light.

Diagnosis continues.

I wired the GYRO up to a 5V supply with no heating apparent.

Made me suspect the CRio.

I measured the voltage on the red/black pins on the analog breakout and got 12V. Hmm not good.

The LED is green, and the input voltage is 12V, but I guess the DC-DC converter on the breakout is bad… Not sure if it’s a new one or not.

Might explain why my 2090 Gyro was drifting badly on this year’s robot.

Off to the parts bin.

Update. ----------------------

Found a spare Analog Breakout…

This one puts out 5V like it should. No hot Gyro any more…

Note: the black chip on the bad breakout was also getting hot…(U1)

Now… wonder if it still works.

Is this a 2010 or a 2009 Analog breakout?

That’s what I meant by “new or not”, I wasn’t there when they assembled the prototype, so I’m not sure. Can you tell them apart?

If there was only one analog module in the 2010 KOP, then the one that went bad must have been a 2009.

Phil.

Eric made the 2010 Analog Breakout blue, while the 2009 one was red.