pic: 3692's PDP after catching on fire at Queen City

[Michael Hill]

loading photo ...

[coolhandluke811]

Could you share more info on this?

-What likely caused it
-How long it took you to fix.

[Michael Hill]

Originally Posted by coolhandluke811

Could you share more info on this?

-What likely caused it
-How long it took you to fix.

Wasn't our team so I can't comment on it.

[Racer26]

Making an educated guess based on the photo?

Looks to me like the positive lead of those wire stubs pulled too much current through the board (possibly by shorting to ground somewhere in the wiring between the PDP+(Speed controller of choice)), overheating it and ultimately igniting the plastic chassis of the PDP.

[Michael Hill]

I will say looking at the bottom of the PDP, there was a distinct burn mark (Unfortunately I don't have a picture) between the 40-Amp breaker slot and the smaller ones. I don't know enough about the situation to say much more.

[Jaxom]

Originally Posted by Michael Hill

I will say looking at the bottom of the PDP, there was a distinct burn mark (Unfortunately I don't have a picture) between the 40-Amp breaker slot and the smaller ones. I don't know enough about the situation to say much more.

I do have a picture, which I will post as soon as I can figure out how to make CD allow me to. One theory was some kind of internal arcing. I'm not on their team either, but I think they've already contacted CrossTheRoads. The "good" news is that they only missed one match while repairing their bot.

It definitely was on fire - not just smoke. In addition to the PDP there was a bundle of CAN wire right next to the PDP that was crisped.

[kpie3692]

Originally Posted by coolhandluke811

Could you share more info on this?

-What likely caused it
-How long it took you to fix.

We are still not sure why it happened but it was definitely not something that we caused. It took us under an hour to replace the pdp, 2 talons and test everything.

[techhelpbb]

So did the field's fire extinguisher get some use?

[Tungrus]

Are you or CRE doing any analysis as to why this happened? If it was a short, the inline circuit breaker or the main breaker should have tripped (it auto resets and finally the main breaker trips), I think.

Curious to know if it the heating started on the PDP PCB (internal circuit board) somehow (possibly a metal chip that got under the cover of PDP), so the bypassed inline circuit breaker did not trip and before the main breaker (120A), tripped it melted the plastic.

[kpie3692]

Originally Posted by Tungrus

Are you or CRE doing any analysis as to why this happened? If it was a short, the inline circuit breaker or the main breaker should have tripped (it auto resets and finally the main breaker trips), I think.

Curious to know if it the heating started on the PDP PCB (internal circuit board) somehow (possibly a metal chip that got under the cover of PDP), so the bypassed inline circuit breaker did not trip and before the main breaker (120A), tripped it melted the plastic.

CRE has contacted us and wants us to send them the PDP for analysis. I'm curious to see what they find and I hope they follow up with us on the cause.

It was for sure a massive short but the inline breaker and the main breaker never tripped throughout the fire. We are very careful with our electronics so I'm confident it wasnt a chip, that only leaves manufacturing defects.

[Tungrus]

Originally Posted by kpie3692

CRE has contacted us and wants us to send them the PDP for analysis. I'm curious to see what they find and I hope they follow up with us on the cause.

Please share your/CRE findings, we all can learn from your experience.

Thanks in advance.

[ayeckley]

Good thinking on somebody's part to have a CO2 extinguisher available rather than just standard Class ABC. That would have made a real mess.

[FrankJ]

Originally Posted by kpie3692

It was for sure a massive short but the inline breaker and the main breaker never tripped throughout the fire. We are very careful with our electronics so I'm confident it wasnt a chip, that only leaves manufacturing defects.

The trouble with the self resetting breakers is that they will set there self resetting, passing enough current to feed a fire. It probably limits the current enough so the main breaker would not trip. Even 40 amps @ 12V will burn things if concentrated enough. Think car cigarette lighter for those of you with cars old enough to have them.

[JamesCH95]

Originally Posted by kpie3692

CRE has contacted us and wants us to send them the PDP for analysis. I'm curious to see what they find and I hope they follow up with us on the cause.

It was for sure a massive short but the inline breaker and the main breaker never tripped throughout the fire. We are very careful with our electronics so I'm confident it wasnt a chip, that only leaves manufacturing defects.

...or a faulty termination.
...or a jammed breaker.
...or a motor controller fault.
...or a wire with some nicked strands from stripping.
etc.

My point is that unless you have some very specific and compelling evidence to rule out everything else (or confirm it was a mfg defect) I don't think that you should be so quick to throw CTE under the bus for this!

For example, if a few strands of one wire contacted the terminal of another wire it would take much less than 40A to heat up those strands enough to light some plastic on fire.

[kpie3692]

Originally Posted by JamesCH95

...or a faulty termination.
...or a jammed breaker.
...or a motor controller fault.
...or a wire with some nicked strands from stripping.
etc.

My point is that unless you have some very specific and compelling evidence to rule out everything else (or confirm it was a mfg defect) I don't think that you should be so quick to throw CTE under the bus for this!

For example, if a few strands of one wire contacted the terminal of another wire it would take much less than 40A to heat up those strands enough to light some plastic on fire.

You're right, I shouldn't have been so quick to say it was an mfg defect.