how to wire the new two motor gearbox

i tried doing a search, but didn’t know what exactly to search for

we never tried a two motor gear box system before, but how do you wire the two motors on the gear box so that its controlled by one joystick (one joystick controls rights side gear box, other controls left side gear box). I know you can only put one motor for each speed control, now we have two motors and two speed controllers for each gear box, do we just use a y connector to hook up the two speed controllers to one of the output of the robot contoller outputs?

thanks

I’m not sure about the rules but from a possiblity standpoint, it will work to use a PWM Y cable. A better (and definitely legal) way would be to use separates PWM cables and outputs on the robot controller, then duplicate the part of the programming that makes the one output work so you have the signla on both outputs.

but aren’t the motors spinning in opposite directions? if you used a Y cable wouldn’t you then be sending them the same signal thus they would be trying to spin in the same direction?

(This is my first year, sorry if I’m way out in left field here)

That is one possibility, and would work. I used a y cable to test my dual motor winch last year. But you can also do this in programming. Thats what my team did with last years gearboxes which used the drill and cim. I would recommend the programming route, it would be more reliable to do it that way. If for some reason a cable becomes detached during the match, you are less likely to lose both pwm cables controlling one side. If you use a y cable, and the cable comes out during a match (say another robot accidentally does that, or it is just loose and comes out due to Violante driving), then you loose an entire drive side. Just the way I think about it.

Drok00 - well that depends on exactly how your transmission is set up, but if you are talking about the transmissions that come in the kit, both motors are spinning in the same direction.

As for direction of rotation, you can “fix” this in programming or reverse the wires on the MOTOR side of the Victor speed control. Never reverse the wires on the power side of the speed control.

I’m going to have to second that one. Also, make sure that power from the breaker panel is going to the power side of the Victor instead of the motor side. We made both of those mistakes in one evening last year, but hey, at least we got to take a Victor apart and see what makes it tick.

ahhh thanks!

but victors arent supposed to tick! :stuck_out_tongue: maybe hum yes but no ticking.

The 2005 victors must have polarity protection. We had several of them wired incorrectly and were wondering whythe panel kept tripping every time we turned it on :-D. However, when we switched the wires, they worked fine, and we have not had victor problems this year.

Jonathan

I have a suspicion.

Spikes come in two flavors. Red and Blue (the labels are diffrent colors). The difference between them, according to IFI’s website, is that Blue spikes have reverse polarity protection. That is, wiring 12v+ to the common stud won’t kill it. Otherwise, red and blue versions are the same.

Victors come in two flavors. Red and Blue. According to IFI’s website, there is no difference, or at least I haven’t seen any published note about there being one.

Could it be that blue IFI components are reverse current protected? I’m not ready to test that theory… Just remeber, if you toast a victor, don’t blame me!

As for the ‘Y’ cable, it is legal for competition. I believe some came in the kit, or have in previous years. They seem to always come with a yellow signal wire. While I would recommend using 4 separate outputs, I can’t think of a really good reason to. I’ve always liked the idea of being able to trim each motor independent of the other, but I doubt it’s ever necessary. I’m sure theres a really good reason to do it, although I can’t think of it. My gut tells me to keep all your PWM outputs separate.

One man, one vote. One motor, one signal. Or something like that.

-Andy A.

The dual motor transmissions have both motors feeding the same driven gear and therefore run in the same direction. A simple “Y” feeding two Victors should work IF you calibrate the controllers.