Melting loop key? SOLVED

ESK8 Electronics
30

and yes 10s

31

thinking about it that does make more sense :sweat_smile:

32

Ok, I thought it was a resistor. All this talk about melting loop keys and capacitors had me second guessing myself. If I’m not mistaken, once the connector is fully engaged, all the current flows around the resistor. But maybe the main connector isn’t engaging/connecting and forcing all or most of the current through the resistor? Not sure what else it could be unless there is massive current draw overloading the connector, but aren’t these rated for like 90 amps continuous?

And fwiw, my setup looks pretty much like @nowind except I’m using XT60s for the battery connections.

33

That is way too far fetched.

1 Like
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That was @whitepony 's theory. He quickly realised that it wasn’t correct.

35

I had the very same problem and everbody told me: “it does not matter how you plug the loop key in”…

Well it did make an difference for me. Here is the thread and to conclude the problem i made the following picture:

Wiring.jpg905×488 30.8 KB

To put it in a nutshell i made the following diagramm:

Wiring.jpg1374×482 55.3 KB

here you can see that the polarity of the XT-90S needs to be switched. Otherwise it melts like mine or yours.

I hope i could help.

PS: Before someone says that this is not the problem please test both wirings and report back :wink:

9 Likes
36

Great! So it must be a polarity issue then! Thanks for the shared wisdom.

I noticed you had yours set up as a break in a serial connection. I have one battery and I am putting my xt90s as a break in the positive lead. Which side in that situation would you believe gets the positive side of the xt90s? The live wire gets the + or the severed wire?

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Actually i do not really know. I would guess that you connect the xt-90s positive with the positive battery cable and the xt-90s negative with the esc. Then it is like mine except two batteries and you put it in the positive wire. But i dont give you guarantee.

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So, sounds like it’s a combination of incorrect connector configuration and higher voltage, like 10s or 12s?

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I dont think the voltage matters… I think it was just the wrong polarity… EDIT: But i dont think you can use 100S with a XT-90S :wink:

1 Like
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Switched polarity same results… I might just keep the regular xt90 and let it spark and I’ll swap it out ever few months

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Did you test it right now? After i switched the polarity of my xt-90s my 12s setup is working flawlessly in FOC :slight_smile:

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Yes I just did. So I think the issue is that there is no “polarity” this loop key is just an interupt in the positive wire. So there is no negative just a positive wire and a wire that is not connected.

43

There is just a resistor in it, and resistors don’t have a polarity :wink:

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I just don’t think it works in the specific way I installed it. As an interupt loop key. It just breaks and closes the circuit

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I noticed you all used it in a manner that had a negative. My situation has no negative so that’s got to be why it doesn’t work

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You mean it should be installed in the negative wire? I cannot test it right now but i would appreciate the result!

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I think it needs to be connected to both the negative and positive wire. So just connecting it as an interupt in one wire it will just melt.

Even tho a regular xt90 will be able to close the curcuit, an xt90s won’t it seems in this particular application

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Many people use a XT-90S as loop key (= interrupt !?) and have no problems at all. I do run 12S with the wiring i showed above and have no problems… Maybe some faulty XT-90S??

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Maybe… can you break one appart and show us whats burned? I really can’t immagine what went wrong here. double checked all your power and balance wires?

1 Like