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Resolved Resolved by Dunning-Kruger!

Red And Black Wires

What do we do if the red and black wires are not there?

We are trying to put our Roli together and do not have the red and black wires that are discussed in step 3.

What can we do to get them. I understand that they should come out at the same place the green, blue, purple, white and black wires came out, but they aren't there.


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I have looked at all the tutorials and pictures - the red and black wires are not in our robot. We cannot connect them because they are not coming up out of him.

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You're cables will work. Match the black wire with the pin with the black base. The other side of the three is white and will connect naturally to the pin with the white base. I see you have a few connected backwards.


On the ezb; inside black pin is ground, outside white pin is signal and middle red is voltage.


@Kidsiteach I think you are missing the Red and Black wires as the Roli directions do indicate, I think they might be down inside the body maybe?

What @DaveSchulpius was pointing about your other servo cables (the 3 pin cables with the white, white, black wires) be careful with those - like Dave said it looks like a couple of those are reversed connected in the picture.

P.S. @DaveSchulpius - the Red and Black wire is from the Roli h-bridge the directions indicate a red and black wire should come out for power along with the multi color pins for controls. My guess was they might be down in the body.


Ahhh, i never built a roli. Thanks for stepping in and keeping it honest. ;)


Yeah that’s an interesting one! Thanks a bunch for sharing the photo, it helps a lot. I wonder if the wires fell into the hole? That’s not something which has happened before, because the wires are quite long. Do you know when and where the Roli was purchased?

Look into the hole of the wires and see if the red/black is visible. Its an option to take it apart with a Philips screwdriver to see - but I understand if it’s easier to simply work with our customer support for warranty (depending on when it was purchased and if it’s used etc).

We’ll get you up and running either way:)

For reference to others (and Justin was right). There’s a red and black wire combo that powers the hbridge of Roli. The tutorial explains how to connect the red and black wires of Roli’s hbridge to the EZ-B. The hbridge requires power from the ARC through those two wires. For more info, here’s a short tutorial on connecting the wires:


@DaveSchulpius, no worries, and good catch on the reversed servo plugs. My eyes didn't catch that until you mentioned it.


Ya I totally didn’t see the reversed plugs either:). Here’s how you connect the wires, the colors matter, just like for the speakers of your home stereo or anything with wires. The black connects to black, and white to white.

Find out more with the robot program. This video was copied from:


a good pic for the the topic here.its easy to connect the wires wrong.check and double check is very usefull.i had it a few times myself.

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I have looked down inside as best as I could and don't see those wires. The kit was bought new through Donors Choose from NASCO. It is not a used kit. I supervised my students as the box was opened and as they completed the first few steps of assembly. I know the wires were not there when we received the kit.

I am reluctant to try and open the base to look for the wires. Could you direct me on how to do this?


Yeah! We found them. They were hiding inside. It was not easy to open, but after trying the 3rd screwdriver, we were able to remove those screws and retrieve the black and red wire. Thank you so much.

Also, thanks to those who noticed our other wires were backward.