Training for offseason tommorow, blew the Main circuit breaker. cause for worry?

[Leav]

Hello,

at the end of a mild practice day, the main breaker got increasingly warm until it stopped working completely (zero continuity).

We switched it out and are OK supposedly, but I am slightly concerned for the offseason tomorrow.

Some background:

• Picture of robot
• 4 cim + 2 mini CIM drivetrain
• 2 CIM + 2 mini CIM kicker
• Bot is about 10 pounds over the max weight (flexible offseason rules)

Is this an expected fault? we haven't had problems before and ran a regional and went to champs...


Your input, stories and experience is welcome!

Thanks,
-Leav

[thatprogrammer]

If the main breaker gets too hot, it will blow. Using all those motors on a 130 pound *without batteries* robot most likely just over stressed it. Was the practice longer than a normal match? The length might have made the breaker get too hot, blowing it.

Some teams that use 6 motor drive trains take a can of compressed air turn it upside down and blow over the breaker to cool it down between matches. This seems to help with preventing blows.

[Leav]

Originally Posted by thatprogrammer

If the main breaker gets too hot, it will blow. Using all those motors on a 130 pound *without batteries* robot most likely just over stressed it. Was the practice longer than a normal match? The length might have made the breaker get too hot, blowing it.

Some teams that use 6 motor drive trains take a can of compressed air turn it upside down and blow over the breaker to cool it down between matches. This seems to help with preventing blows.

When you say "blow" do you mean "trip" (i.e. just pop it back), or "fried" (i.e. something inside is irreversibly damaged)?

And yes, the practice session was longer than normal.... with a lot of anti-t-bone maneuvers... (so high amps)

[thatprogrammer]

Originally Posted by Leav

When you say "blow" do you mean "trip" (i.e. just pop it back), or "fried" (i.e. something inside is irreversibly damaged)?

And yes, the practice session was longer than normal.... with a lot of anti-t-bone maneuvers... (so high amps)

Depending on how hot it gets, either can happen. If it fried I recommend checking the size of your battery cables. Are they up to spec? Normally the breaker would trip before frying. I recommend spraying it with the air just to be safe. ALSO, if you accelerate and then decelerate very quickly, it can be a big stress on the breaker. If you need code to slightly slow down your deceleration, you can pm me for some pseudo-code.

[Al Skierkiewicz]

Leav,
The breakers are temperature sensitive devices. If the wire was loose on the either or both of the terminals or the wire part of the terminal, the temperature would rise causing the entire breaker to be warm to the touch. It is possible that is all it was. When the breaker is warm it is likely to trip at a lower current.

[Leav]

For posterity I'd like to comment that it was a misdiagnosis. We ended up finding a loose connection underneath some electrical tape... False alarm!

Thanks for the help, and sorry for the bad info...