Electrical connectors on control system items

[timytamy]

Originally Posted by Christopher149

The screw connector for powering the roboRIO (and previously cRIO). I don't know if we were using it wrong, but especially on the cRIO, the wires would too frequently come out or be loose.

I like to call screw terminals like these the best bad connector you will use. They're relativley versitile, flexible, easy-ish to use with medium pincounts. However they will never be better than a more specilised conector.

On to the OP's question:
I'm not interested in any new connections unless there are some very good reasons. Inventory management is a PITA, and it's much easier to maintain an inventory of 100x of one conector, vs 25x of 4 different ones. For this reason I'm willing to make reasonable comprimises on all the advantages/disadvantages you mentioned, for connectors already in common use.

This is all the more important if your intended market is ALL of FRC, ie not just the average to powerhouse teams that already have things like this worked out. Having helped many rookie and low-resource teams wire up robots, trust me when I say there is enough in the combination of Wago, Weildermuller, [3-pin only] PWM etc already.

It's a little different if your targeting just the medium-powerhouse teams. As other others have already mentioned Powerpoles, custom .1in (ie other than 3pin PWM), rings and spades, IDC, USB and ethernet etc all have some really good use cases.

[GeeTwo]

Originally Posted by timytamy

On to the OP's question:
I'm not interested in any new connections unless there are some very good reasons. Inventory management is a PITA, and it's much easier to maintain an inventory of 100x of one conector, vs 25x of 4 different ones. For this reason I'm willing to make reasonable comprimises on all the advantages/disadvantages you mentioned, for connectors already in common use.

This, this, this.

Also, while many teams have Power Poles as an internal standard (3946 among them), I am not aware of any standard FRC parts which require/strongly encourage teams to use them. They do meet all the requirements (current capacity, well insulated, vibration resistant) and many "desirements) (modular, customizable, polarizable). They also have a great customer base outside of FRC (ham radio and R/C modeling, and probably others).

[wireties]

My biggest concern is non-latching connectors. In a high-vibration and relatively high shock environment like a FRC robot it is mal-practice to use non-latching non-polarized connectors. They don't have to be fancy or super expensive but really should have a latch.

And like other posters, I prefer screw-type terminals.

[Peter Johnson]

Originally Posted by wireties

My biggest concern is non-latching connectors. In a high-vibration and relatively high shock environment like a FRC robot it is mal-practice to use non-latching non-polarized connectors. They don't have to be fancy or super expensive but really should have a latch.

While power poles aren't natively latching, we use the little orange clips that powerwerx sells. They're easy to install and have been very robust for us. My only other complaint with power poles is that the crimp doesn't grab the insulation (only the wire) so pull-out can be an issue. We make sure to tug-test every crimp and prefer the 45a contacts for all but the smallest wires as they seem to grab the wire better.

[wireties]

Originally Posted by Peter Johnson

While power poles aren't natively latching, we use the little orange clips that powerwerx sells. They're easy to install and have been very robust for us. My only other complaint with power poles is that the crimp doesn't grab the insulation (only the wire) so pull-out can be an issue. We make sure to tug-test every crimp and prefer the 45a contacts for all but the smallest wires as they seem to grab the wire better.

We use wire ties to make sure the power poles stay together. I always forget to buy the little orange clips.

[Gregor]

Originally Posted by wireties

We use wire ties to make sure the power poles stay together. I always forget to buy the little orange clips.

Tiny zip ties work really well for securing PowerPoles too, that's how I've always done them.

[GeeTwo]

While power poles don't natively latch, they do natively restore a temporarily loosened connection. Retention is not through friction, but through the spring force of the two contacts. If the contacts are properly assembled, and the cable is not under tension, the contact won't just vibrate loose; it would take a shock load in which the connector's inertia provides the breaking force. If you partially disengage a power pole and release it (or don't engage fully on insertion), the spring contacts will [re-]complete the engagement for you.

[taichichuan]

I'd have to second the comments about hating JST connectors. While the retention is fairly good, these connectors are nearly impossible to fabricate reliably.

The T-plug connectors are fine for singleton connection. But, we frequently find ourselves with bundles of cables that the APPs allow us to gang together and key the connection in such a way that the connections can't be mis-connected. Yes, you really need the specialized crimper. But it's less than $50 and most other types of connectors (like the .1" PWM connectors), regardless of the type, require a specialized crimper to do it right.

The XT60 connectors are like the T-plug connectors. Great for singleton connections. The mechanical connection seems more robust to me over the T-plug connections. But, these connectors look like they need a special crimp tool or need to be soldered. So, I don't really see that these are any better than what we have already.

HTH,

Mike

[Chris is me]

228 uses Deans connectors and I think they're fine. You have to solder the wire to them, sure, but other than that they are a robust connector that clips together securely and nicely. Soldering and shrink tubing the wires to each lead helps them hold securely. Never had an issue with them failing a pull test.

If you go all in with the tooling, Anderson connectors are very robust. I don't particularly care for the whole snapping multiple connectors into one big block thing. Spade connectors are okay I guess.

Almost any connector, latching or otherwise, can be made more secure with heat shrink tubing to hold it together. It's difficult to accidentally pull apart a spade connector if the tubing constrains it geometrically.

[otherguy]

I'm personally not a big fan of JST connectors for items that need to be plugged in/out with any frequency. I find the pins to be easily damaged if you try to seat a connector that's not properly aligned. As a result they are nearly impossible to plug in to a sensor that's buried in the robot. The Sharp IR sensors have this style connector on them, and we always terminate an adapter cable to 0.1" header pins in the event something needs to be swapped out between matches.

For a low conductor count cable (like PWM you mention) what would be the advantages of a JST connection? The only thing I can think of is that it's keyed, can't see there being appreciable space savings on a 3 pin cable.

For the XT and Deans connectors, I don't have much experience with them myself, but i know they are the standard I'm the hobby RC market. I'm open to their use. Instructions on how to connect to them correctly, tools required, what gauge cable, sources for tested wire & tools, tips/tricks would probably be helpful for most teams as I'm not sure I've ever seen one on an FRC robot in the past 8 years. Maybe I'm not looking hard enough.

I'm a fan of male/female spade terminals. They're cheap and reliable when crimped correctly. We usually mount little right angle male spade adapters on all motor controllers with screw terminals so that they can be swapped out quickly.

Sent from my LGLS751 using Tapatalk

[mman1506]

I have a lot of experience with XT connectors as they are connector of choice for personal projects. I used to use Deans connectors but they are much easier to melt when soldering and occasionally the spring tabs would bend ruining the connector. XT connectors are also easier to solder than Deans because of the cups on the terminals.

Personally I would rather solder connectors than crimp as it requires less specialized equipment and lessens the chance of a intermittent or high resistance connection which can be very difficult to diagnose.

Another advantage of RC connectors is that they are gendered(male and female) unlike Anderson connectors. This prevents a user from plugging a battery into another battery or the motor side of a speed controller into a power source and destroying it.

I've never been a fan of JST connectors, they are very low amperage and only really useful for something like LEDs. They are also difficult to grip and pull apart without tugging on the wire.

[Sparky3D]

I personally prefer powerpoles over both the Dean's and XT connectors. You have to have a proper crimper for them, but once you do, they are pretty hard to mess up. Our electrical students use them wherever possible because they are quick, easy and they rarely have issues with them. Our students soldering ability tends to vary a lot, so soldered connections tend to require more TLC to ensure everything is solid.

[MattRain]

Originally Posted by Greg Needel

[*]Anderson Powerpole - main battery connector & commonly wire to wire connections - medium price, good quick release, hard to crimp without special tool

Deans connectors - https://www.amazon.com/dp/B00S7G4A14/ instead of power poles or wagos

Deans Connectors: Hate these things. A'lot of RC's use them, but I've always had issues with them.

Anderson Power Poles: Go with these. I absolutely love these. FTC switched over to a new control system that uses these in pretty much everything, so my teams have a large stockpile of them. After having the right tool, they are easy to work with! My teams love the fact that you can create large blocks of connections, which has already been said in this thread. Allows us to remove parts easily to work on parts of the robot or to switch out. Some of the electrical students on my FRC team saw them this past year, and want to make the switch to them next season.

[AustinSchuh]

Molex connectors (http://www.molex.com/webdocs/datashe..._HOUSINGS.pdf). They are polarized and latch pretty well. We've gotten pretty good at crimping them.

[Jefferson]

Originally Posted by AustinSchuh

Molex connectors (http://www.molex.com/webdocs/datashe..._HOUSINGS.pdf). They are polarized and latch pretty well. We've gotten pretty good at crimping them.

Looks like you got that close parentheses in your url. Here's a working link.