Radio Cable Burning!!!

[Al Skierkiewicz]

It sounds like your modem is working if you are running for a few minutes before the wires start to burn. If this is the case, it sounds like the power supply in the RC has gone bad. It is likely feeding raw 12 volts to the modem. This requires a call to Innovation FIRST. You likely have to return both the RC and the modem. This is the first time I have heard of this condition.

[Cadetdan]

Ok well we burned up 2 more radio cables this morning. And now the RC is acting funny......it works but all the LED's are out. So yeah I dunno what went wrong but I guess ill have to send it to the US first people. What might have caused this? We never fool around with the RC we took it right from the box and put it on the bot! Aight well thanks for the help!!!!

[KenWittlief]

dont send it to FIRST - you have to contact these people www.innovationfirst.com - its a separate company that makes the control system and sells them to FIRST

[Al Skierkiewicz]

Originally Posted by Cadetdan

Ok well we burned up 2 more radio cables this morning. And now the RC is acting funny......it works but all the LED's are out. So yeah I dunno what went wrong but I guess ill have to send it to the US first people. What might have caused this? We never fool around with the RC we took it right from the box and put it on the bot! Aight well thanks for the help!!!!

Let us know what the outcome is, please. With all the LEDs out and everything else having problems, I am still voting for a 5 volt regulator failure. That is bad news.

[Dave Flowerday]

Others have provided a lot of answers for you but I'd like to add a general guideline. If wires get hot enough to melt or burn, there's a major problem somewhere. Whenever this happens you should shut everything down, disconnect any power sources (like the battery), and start checking everything. Don't bother turning anything back on until you find a real problem that's been fixed, or you'll just burn up more wires (as you apparently found out).

Hope you find your problem soon!

[tenfour]

If the radio was working fine, it sounds like there is a problem with the system before it. I would switch the cable. Also check for type of conductor bridge between the pins and/or connectors. Just blow hard on the end. There could be some type of metal chip in there. If you have to, just return it and make hem ship it out next day. Good luck.

[sanddrag]

We had an edu motor with a little spec of metal shorting the two pins on the circuit board and it would not work at all. Then we removed the offending debris, and it now works great. Kind of similar.

Anyway yeah, the cable may be grounded to a common ground somehow, and if you have a power wire touching the ground somewhere, it may cause the problem. Also, shouldn't a breaker be tripping before wires start burning? I mean, that's what breakers are for right?

[Al Skierkiewicz]

Originally Posted by sanddrag

Also, shouldn't a breaker be tripping before wires start burning? I mean, that's what breakers are for right?

Sandrag,
This is another of those little inconsistencies in electronics/electrics. The modem is fed power from the RC which in turn is connected to a circuit breaker. Normally the power supply in the RC will limit the voltage and current being fed to the modem. The cable used to feed the modem may have wire as small as #30 which can only handle a fraction of an amp. If the modem-RC has some form of failure and more than a fraction of an amp flows, that is sufficient to heat the wire but not trip the circuit breaker. At some point the wires will begin to short together when the insulation has been comprimised and then the current gets high enough to trip the breaker. Since these are auto resetting breakers, the condition continues until the operators get tired of the smell and smoke and turn off the power to the RC/robot. There are also internal auto resetting breakers inside the RC. They replace the fuses used in the previous version of the RC. The current on the modem was fused for 0.5 amps in that version.