Magic Smoke and Shrapnel

[Cody Carey]

Our chain came apart


We were running it at 4000 RMP, and the cnain hit a peice of lexan just right so it unclipped the masterlink...

That was scary

[Bemis]

I missed that, Cody, when did it happen?

[Cody Carey]

When you were at district jazz, I think.

no double posting kids....lol

[Taylor]

In the words of one of the students as he was working with our launcher prototype, "The real surprise came when it bounced off my face." He wasn't referring to the ball, by the way.
Make sure your screws and bolts are tight, boys and girls!
Oh, and we got magic(k? Aleister Crowley lives again?) smoke from our joysticks earlier. That was interesting.

[Taylor]

Originally Posted by pyro20911d

no double posting kids....lol

You got it.


Wait.


Um.


Shoot.

[Hieb]

We did get a little magic smoke this year--apparently Victors don't like having the battery wired to the motor side. At least we had some fun pulling it apart and looking at the damage.

[Sachiel7]

Yeah, make sure that youre running your Victor's for any spinwheels in Coast mode. Trying to brake them can cause some bad results if they're still spinning too fast. At least for our team, that helps.
Make sure your shooters are well enclosed too.

[KenWittlief]

Originally Posted by Sachiel7

Yeah, make sure that youre running your Victor's for any spinwheels in Coast mode. Trying to brake them can cause some bad results if they're still spinning too fast. At least for our team, that helps.
Make sure your shooters are well enclosed too.

Im surprized to hear that (actually I am shocked and dismayed :^)

if the Victors can spin a motor up, it should be able to coast or brake it

in fact you should be able to spin the shooter up to full speed, then throw it into full reverse (to stop it) without hurting the victors.

But then again, maybe the shooter wheels being built this year are using them in ways they have never been used before? If you blow one out using it this way I would definately send it back to IFI for failure analysis.

And if we start seeing a lot of victors fail on shooter wheels, it would be useful to instrument one and see how much voltage and current it is seeing when it brakes the motor.

[Mike AA]

Originally Posted by KenWittlief

Im surprized to hear that (actually I am shocked and dismayed :^)

if the Victors can spin a motor up, it should be able to coast or brake it

in fact you should be able to spin the shooter up to full speed, then throw it into full reverse (to stop it) without hurting the victors.

But then again, maybe the shooter wheels being built this year are using them in ways they have never been used before? I you blow one out using it this way I would definately send it back to IFI for failure analysis.

And if we start seeing a lot of victors fail on shooter wheels, it would be useful to instrument one and see how much voltage and current it is seeing when it brakes the motor.

I will run an inline amp test in about an hour or so and post how much ours takes. Given that it runs at about 31A it'll probably be close to twice that ?

-Mikw

[KenWittlief]

I would expect you might see 100A on the motor for a brief period. A DC clamp-on ammeter might be the best choice.

[orelinde]

WOW and i thought you meant sparks flying when your robot hits another robot and flames shootingt into the air and the balls are shot at the target and smoke pour out when your robot hit the ramps silly me. pyrotechnics is where i was thinking. **runs to talk to team**

When one refers to magic smoke he/she is referring to the smoke that comes from faulty wiring or electronics.

check out this link for the real definition............you must read this short article in order to fully understand what "magic smoke is"................there's more to it than what I explained to you.

[Mike AA]

Originally Posted by KenWittlief

I would expect you might see 100A on the motor for a brief period. A DC clamp-on ammeter might be the best choice.

Sorry didn't have a chance to run the amp meter. I have a dc, inline amp meter capable of over 600amp, DC. I simply bolt the wires to the lugs on the shunt and turn the meter on and the device, I have used this for numerous items, including a 2500watt dc to ac inverter (capable of over 500 amp surge at 12volts). I wont get the chance to hook up again until probably saturday but will post my findings.

-Mike