Electrical Connectors

[DonRotolo]

Al, I think he's referring to the small powerpoles, designed to use the roll pin to hold them together. An assembled black/red pair can be zip tied together, but what keeps red and black next to each other?

We don't use super glue, instead some far weaker glue, just enough to gum up the dovetail so it doesn't come apart easily.

Woe to the team that uses the metal roll pins: They WILL come out and short power to ground, these should never be used.

[Al Skierkiewicz]

Don,
There is a clamp that fits over a dual Power Pole mated pair. They are black and snap over the connector block when mated. You can see the variety of them here listed as Blok-Lok...
http://www.powerwerx.com/anderson-po...s/accessories/

The roll pin is designed to keep the red and black pair from sliding apart during mating.

[DonRotolo]

Wow Al, something new! Thanks.

When I use PowerPoles for home stuff, I just let them stay together with friction. But gluing them doesn't cause problems - if the contact fails, we can replace it, and if the body fails, it gets discarded.

[Dale]

This year we used spade connectors on our Jaguars with the Tyco tabs. It was terrific when we needed to switch out a Jaguar or move them around. We had quite a few problems with them coming off, though. Especially given the trauma of going over the bumps.

What we found was we had to be careful to bend the 12 gauge wires such that they naturally wanted to push the connectors in.

We were using normal Home Depot female spade connectors. Are there any that grip more firmly? It happened enough this season that the team is ready to try hook connectors next time.

[kstl99]

Originally Posted by Dale

This year we used spade connectors on our Jaguars with the Tyco tabs. It was terrific when we needed to switch out a Jaguar or move them around. We had quite a few problems with them coming off, though. Especially given the trauma of going over the bumps.

What we found was we had to be careful to bend the 12 gauge wires such that they naturally wanted to push the connectors in.

We were using normal Home Depot female spade connectors. Are there any that grip more firmly? It happened enough this season that the team is ready to try hook connectors next time.

Be aware that spade connectors come in two sizes for tab thickness, .032" and .020". If you have the wrong ones they will come apart but the correct ones usually come off hard to the point you sometimes need needle nose pliers.

[Dale]

I've never seen anything other than .032 for 10-12 gauge spades. For smaller gauge wires they do come in two sizes. Is there a special source for these? Our tabs seem to be .032 for what's it worth.

[kstl99]

Originally Posted by Dale

I've never seen anything other than .032 for 10-12 gauge spades. For smaller gauge wires they do come in two sizes. Is there a special source for these? Our tabs seem to be .032 for what's it worth.

I just looked it up and found that the 10-12 do only come in .032". I was wrong (I hate it when that happens). Perhaps it is the Home Depot quality. My favorite are Thomas & Betts but there are many good brands. Could it be that they were not fully inserted onto the tab? Maybe you need to get Tyco lugs to use on the Tyco tab as it may have a detent that works better with their lugs. I just know that in too many years of machinery wiring I have not had the problem of them falling off.

[Steven Sigley]

On Powerpoles I'll vouch that these things are magnificent.

http://www.powerwerx.com/anderson-po...ch-4-sets.html

http://www.powerwerx.com/anderson-po...nt-4-sets.html

Used 2 on the electronics box in 2009. Worked wonders for making electronics removable. Could connect and disconnect 8 wires in like 1 second flat.

But make sure you get the crimping tool, we made the sorry mistake of not doing so, and struggled with getting them in their housing before putting them in the chassis mount. Otherwise things would've gone much more smoothly.

All in all, great solution if you're trying to make a removable electronics panel or box.

[Al Skierkiewicz]

Dale,
We have been using that arrangement for years with a few twists. We use the uninsulated female connectors and #10 wherever we can for high current loads. Once crimped we then solder the connection but adding only enough solder to make the connection with none flowing under the wire insulation. We then cover the entire connector with heatshrink right to the end. The heatshrink not only insulates the entire electrical contact but it also provides a little extra compression on the contact. We use perforated aluminum as an electrical base which allows a light mounting surface and something that allows tywraps to be used anywhere. As you described, pulling the wires down to the surface near the contact then allows the tywrap to hold the wire in place, prevent vibration and makes it look a little neater.
Why you ask? We never want to lose a Championship to Beatty because of an electrical failure, ever again...

[Dale]

Al,
Thanks for the validation. If it's good enough for you folks it should be good enough for us! The key seems to be to not rely on the spade connectors to hold any more than a couple of inches of wire on the tab.

This season we used velcro sheets on an expanded foam PVC control board and 4" wide velcro on the jaguars. Everything stayed put with nary a problem. It was fantastic for changing our mind and easy to pull off a part if it died.

The downside is fastening down wires is more of a pain as the velcro isn't strong enough for that with a normal 1" pulltie pad. We still had to drill through the sheet which meant it didn't get done so often. A lesson learned. We might look around for some other method or posts for holding the wires in place. I hate to go to a perforated conductive electrical plate but I can sure see the advantages.

[vhcook]

We used masonite pegboard to mount the electrical system (the kind you'd use in your garage for tool storage). It's cheap, light, nonconductive, has plentiful holes, and is strong enough if you provide it with adequate support and protect it from direct impacts. I've been using it for four years with two teams, and have never had a structural failure, even with the robot taking some fairly hard hits.

We use ty-wrap for speed controller mounting and wire bundling, and screws for the heavy parts like the cRIO and the PDB.

We've been using the more normal hardware store quick disconnects, but I'm considering a move to the Anderson powerpoles for next season.

[Al Skierkiewicz]

Dale,
The conductive material has not been a problem. Everything you mount has insulation and the perf stock is not connected to any electrical part of the robot. We mount the perf stock with rivets to the frame so even if the whole system needs to be replaced, a few rivets drilled out and it comes out in your hands (usually). Depending on the design of the robot, the perf stock is in sections and distributed throughout the frame. Pretty easy to custom fit with a pair of metal shears.

[ayeckley]

Originally Posted by Don Rotolo

Then get good wire. Not at Home Depot or Lowes (or Radio Shack). Go to McMaster or DigiKey or Jameco (and others) and buy good automotive-grade (can handle 60C or better) wire. Buy a few sizes (10 to 22 AWG) in Black and Red (and white for the 22 Gauge), a few hundred feet of each (maybe only 100 feet of the biggest stuff, it gets expensive).

We discovered Marine-Grade (ABYC) wire this year and love it; specifically Anchor Marine wire. Similar to Automotive wire, except with a higher number finer strands.

The upsides:

• Very flexible, even compared to automotive wire (almost as flexible as silicon-insulated).
• The strands are tin plated so shelf life/oxidation is not a problem.
• It's sold by the foot, so it's not necessary to buy more than you need for a single season.
• It's available at a retail location even in the winter (near us at least; no need to mail order it). Spools sometimes show up on eBay as well.
• It's got the necessary labeling and pedigree for inspection purposes.
• When purchased by the foot, it comes off of large diameter spools so it doesn't have that annoying small diameter kink to it.

The downsides:

• Cost; it can be a bit spendy ($0.93/ft for 12 AWG), so we only use it when we need heavy gauge wire (10 AWG thru 14 AWG).

We haven't used it with APP connectors yet, but don't anticipate any issues. We generally try to avoid unnecessary connectors as has been discussed already. We're still using EV cable (essentially welding cable) when 6 AWG is called for; very similar to the new (flexible) battery pigtails that came in the KOP this year.