Our team is thinking of switching from the push in connectors that are included in the KoP to some higher quality connectors. I had the idea of using xt60 connectors, and found a Chief Delphi thread that talked about it and said it should be good. (thread here )
My inquiry is about using both an xt60 connector and an Anderson powerpole connector for the 3 wires to brushless motors. The SparkMax controllers designate the black and red wires as for brushed motors, and for brushless using those and the while wire. I want to put an xt60 on the Black/red, and an Anderson on the white.
My question is mostly would this be acceptable to judges? All connectors are rated for at or above their fused amperage, so I canât see a mechanical reason why this wouldnât work, but what are otherâs thoughts?
It would be legal and get passed by inspectors, but mixing and matching connectors like that seems like a waste of resources and additional things to order and stock. Get good at one connector and run with it.
Slightly pedantic, the judges likely wont care at all (though nothing is stopping you from trying to spin it into something award worthy). The Robot Inspectors are the ones you should be concerned about, as they will be the ones to decide if the bot is legal (and in turn, get to play in matches).
To your question, I cannot speak to the xt60âs, but andersons for sure will work. We used them with success in 2020. You can see how we did ours with a NEO motor in the bottom right.
There also are MT60s, which seem very similar to XT60s, except with three contacts instead of two, but theyâre far less common. Iâm personally a fan of Andersons, for all the reasons others have said so far as well.
MT60s also fit in tighter spaces than any of the connectors mentioned here. Iâm a big fan of them in larger brushless applications where Andersons arenât quite as universal.
We also use the MT60âs on our NEOs. Just make sure you pick a pinout and stick to it so you can mix and match motors; especially since we seem to kill NEOs and NEO550s more often than Falcons or the CIMs we used to use.
Not to derail the thread, but in what applications are you killing neoâs?
Additionally, have you killed falcons? Your comment possibly suggests that you have.
We have a few of each, but definitely havenât put them through their paces.(2020 cut short) Due to their brushless nature, we expect to get a little more life out of them than our typical 1 season and done like has been the norm for their brushed counterparts. Replacing drivetrain motors is maybe a given, even with brushless, but for other applications where we arenât working them hard we would hope they could see more than one season of play. Especially the Falcons. Those bad boys are pricey!
To weight in on the subject at hand, my recommendation is to standardize connections on the robot and to avoid mixing and matching on individual runs.
Weâve had various self-inflicted and mysterious Neo failures. Weâve had no Falcon failures since we started buying them but that was only 2020 so not a lot of battle experience with them.
In addition to having to rebuild f*ing JST connectors, we had an encoder cable experience an intermittent break where it enters the housing.
We burned out the coils on a NEO-550 when our storage jammed (poor design decision on our part).
We burned out a couple coils on a NEO and couldnât identify âwhyâ.
Something something mounting screws too long interfering with inner housing and stripping a thread (over exuberance on the part of a student).
However, I will say the MT60s are tough to solder. The leads are close together and any extra solder will prevent the cover from going on
Personally, I almost regret going with the MT60s for my team. We use XT60s a lot because of issues I had crimping andersons. MT60s are tough to do, but overall are better for feeding through holes and cleaner/match the existing connectors
Itâs worth noting the â60â in MT60 (and I think also XT60) is a max instantaneous current rating. The continuous current rating is half thatâso 30 amps. So you potentially shouldnât be using these with a 40A breaker. Doing so is arguably violating a robot rule, but I doubt most robot inspectors will call that out. Personally I would think the actual rating in a FRC application is somewhere between those two ratings given we arenât operating at worst case temperatures and only for 2-3 minutes at most continuously, but that is a little counterbalanced in my mind by the potential for poor soldering quality by inexperienced students (crimping is easy to get right with the right tool with much less experience).
I like that you got white Anderson housings for the white wires, too. It keeps the whole setup nice and clean, with very little chance of an incorrect connection. And you pic is a perfect example of why this works so well for these three wire connections. You can block the three Anderson housings together and use two of the Powerwerx retention clips to keep the whole thing solidly connected pretty much no matter what happens.
Iâve had consistently terrible crimp experiences with ~$24 Amazon iwiss tools, and excellent experiences with ~$50 powerwerx Tricrimp.
Itâs possible you got a bad tricrimp too, theyâre at a low enough price point that Iâd expect one in a hundred to one in a thousand to have quality issues, but Iâm at 3/3 excellent tools anecdotally.
(Our team has both smoked phases and fatigued output shafts on the neo550, but thatâs due to some pretty terrible design choices on our part. No mileage on big neo. I worked with another team that managed to smoke a phase on a falcon500 in their drivetrain, operating without any current limits in code. Unknown ratios, pneumatic tires on all corners.)
Honestly, a declaration of âpink is for motorsâ is kinda geniusâespecially for teams who still have brushed motors in the mix (even I have to look closely at an OG SPARK to make sure I got it right). Might explore that in the off-season; itâs not like changing out PowerPole housings is a big production.
1293 braids its NEO and SPARK MAX cables to keep them from getting tangled on things, a tip we stole from Spectrum. The main thing we have to do is ensure we got the red-black-white slotting order consistent across each connector. If not, undo the joint and swap them back around. The ability to slap whatever SPARK MAX into whatever NEO makes assembly and maintenance super simple.
I encouraged my team to use green/white housings for the motor side and red/black for power side. And this was even before the TalonSRX came out with the green/white wires. Unfortunately we had picked the opposite coloring they did (we did green+ white-) so there was some wires to swap around. In any case, +1 to utilizing different housing colors for different things.
We have managed to kill a falcon. It was mounted directly on our shooter drive shaft instead of offset and driving with a belt. It basically shook to death. Have not had any problems with falcons over heating even with extended driving times during practice.
