I'm using a cc bec pro with castles ESC and instead of cutting the red wire from the esc I cut the black by mistake. I actually ran the for a pack before noticing.

Does it matter which one i cut?<br />

Thanks

You should repair the black wire, and extract the contact attached to the red wire from the connector. The black wire is the ground and reference for the signal, and ties the negative of the flight battery to that of the receiver. With the black open and the red connected, you risk the ESC not responding properly.

Thanks a lot. What is the name of the black tab and the small pins that goes into it? Wanna get a new one to fix my mess

Dont't worry about it. The receiver is still tied to battery ground through the bec pro. If it wasn't nothing would work. Simply remove the ESC red wire and all will be fine. If you should want to run the ESC without an external BEC then you will have to reconnect the ground (black) wire.

In future, don't cut the wire. You can easily remove the pin from the connector by depressing the small tab on the exposed portion of the pin in connector and pulling the wire, pin and all, out of the connector. Then if you need to use the wire again, simply reinsert the pin into the connector.

Larry

It's good practice to have each component connected to the receiver by at least it's ground lead (black). Sure, they often work without a direct connection because the current will find another path, but that could overload something else and/or cause erratic response.

So, best to repair the black lead. The "black tab" is called a servo plug -- you can buy them with separate pins for crimping onto the wires, like the ones near the bottom of this page http://www3.towerhobbies.com/cgi-bin...RCH=servo+plug. If you don't have a crimper (further up that link), you might be better off doing a solder repair to the wire you've cut.

On the other hand, did you actually cut the black wire, or just pull its pin out of the plug? If you pulled it out, just push it back.

He cut it.

Here's some pictures -

I take it Ray you don't mind me copying/using the above pictures to/in www.modelbouwforum.nl ? Should a add your name/username to the pictures then?

Attachments below are not mine.


Vriendelijke groeten Ron
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Ron, Ok to use whatever pictures you want, no need for a name.
Thanks.

Thanks a lot gents. Knew it was best to ask it in the aircraft section, you guys know your electronics

Originally Posted by xenogears

I'm using a cc bec pro with castles ESC and instead of cutting the red wire from the esc I cut the black by mistake. I actually ran the for a pack before noticing.

Does it matter which one i cut?<br />

Thanks

Let me chime in and say I would fix the black wire. If I understand what you are doing you still need the throttle control from the receiver to the ESC. By cutting the black wire you have an unbalanced transmission line (signal and ground should be equal). The chances of a ground loop, imo, are fairly high.

Originally Posted by Rich in ILM

Let me chime in and say I would fix the black wire. If I understand what you are doing you still need the throttle control from the receiver to the ESC. By cutting the black wire you have an unbalanced transmission line (signal and ground should be equal). The chances of a ground loop, imo, are fairly high.

Correct- from a transmission line standpoint the current wants to travel back to the source in the tightest loop possible. This is with a ground wire right next to the signal wire. This also reduces noise generated by the wiring, as well as making it more resistant to outside interference.

Originally Posted by Rich in ILM

Let me chime in and say I would fix the black wire. If I understand what you are doing you still need the throttle control from the receiver to the ESC. By cutting the black wire you have an unbalanced transmission line (signal and ground should be equal). The chances of a ground loop, imo, are fairly high.

You must be joking. Since when is the cable between the receiver and the ESC considered a balanced transmission line? The black return wire is connected to ground which by definition makes the transmission line unbalanced. As for a ground loop, since the receiver and the ESC are already connected to ground via separate lines, having no direct ground connection between the reciever and the ESC eliminates the possibility of a ground loop. Connecting the grounds between the two completes the circuit and sets up the possibility of a current flowing through the ground wire because of different ground potentials between the two devices thus setting up a ground loop.

Larry

Originally Posted by Lnagel

You must be joking. Since when is the cable between the receiver and the ESC considered a balanced transmission line? The black return wire is connected to ground which by definition makes the transmission line unbalanced. As for a ground loop, since the receiver and the ESC are already connected to ground via separate lines, having no direct ground connection between the reciever and the ESC eliminates the possibility of a ground loop. Connecting the grounds between the two completes the circuit and sets up the possibility of a current flowing through the ground wire because of different ground potentials between the two devices thus setting up a ground loop.

Larry

You are neglecting the fact that the ESC is putting strong current pulses on its return to the battery, causing a voltage spike with each pulse, which doesn't occur at the receiver. Without the ground to the receiver, the reference for the input pulse detector in the ESC will see a much noisier signal. Without testing, one can't be sure if the noise would be enough to make the ESC behave erratically, but there is the possibility.

Originally Posted by Lnagel

You must be joking. Since when is the cable between the receiver and the ESC considered a balanced transmission line? The black return wire is connected to ground which by definition makes the transmission line unbalanced. As for a ground loop, since the receiver and the ESC are already connected to ground via separate lines, having no direct ground connection between the reciever and the ESC eliminates the possibility of a ground loop. Connecting the grounds between the two completes the circuit and sets up the possibility of a current flowing through the ground wire because of different ground potentials between the two devices thus setting up a ground loop.

Larry

So you are suggesting that it is better to have the throttle return line from the receiver through the stand alone BEC then the battery? We must be evisioning different circuits. That can't be what you mean?