[FTC]: Using Anderson Connectors for wiring.
 

I found this document via Twiter:

http://www.usfirst.org/sites/default...pole-Guide.pdf

It's a pretty cool description of a different way to connect your motor/servo controllers. And since it's on the FIRST site I assume it's legal.

I just checked out the link to the parts, and they are are suprizingly inexpensive. $11 will get you eveything you need for 5 connector sets. The only real expesne is the crimper if you want a nice one.

One of the additions I'd make to the idea is that you should replace the connector on your charger to be one of these Anderson types as well, and use it to plug into your system to charge the battery.

The problem that we had last year was that the current battery connectors don't seem to be designed for the hundreds of connect/disconnect cycles that we put them through. Eventaully the copper pins loosen up and start glitching on robot-robot impacts. What look like telemetry dropouts are actually power resets on the Samantha module.

The Powerpole connectors have stainless steel springs built into the connectors so they are rated for 10,000 connect cycles. Plus they are rated for 45 Amps.

The bonus is that if this system removes the multiple wires in a screw terminal issue and the need to pull wires to replace a motor controller.

The additional connectors may add a bit of bulk, but if it increases reliability it's worth it. Mine are on order now !!!!

Phil.

Re: [FTC]: Using Anderson Connectors for wiring.
 

In the past it has not been legal to change the connector attached to the battery, I believe, which would be why the document doesn't show this being done.
Nope, I see what you mean. Good idea.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Yeah,

It would be great if we could change the battery connection, but even if we can't, using the proposed wiring we could just change the connector on the charger (or even make an adaper cable) and plug in the charger dowsntream from the power switch (using the Anderson connector).

You'd just need to make sure the switch was ON when you went to charge.

The existing battery connector is fine, as long as you don't make it loose from many hundreds of connections.

ps: I do think we should lobby for being able to change the battery connector if we are fine with voiding the warrentee :)

Phil.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Phil,
As much as I like these connectors (we have used them for years on our FRC robots) under 2011 rules they are not legal for FTC. Specifically, they are not official Lego or Tetrix parts and are not on the allowed materials list. While 2011 rules do allow for splicing electrical connections, they specifically call for tape to insulate such connections.

However, if you check my other posts on this subject, you will find that I highly recommend the West Mountain Radio crimp tool. We use these connectors for all FRC motor connections and a variety of other uses on our robots. If FTC rules will allow these in the future, I expect that battery connectors will be required to remain as they are provided from the manufacturer. If for no other reason than to have compatibility between teams.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Since the 2011/12 rules are yet to be released, I don't know if they are legal or not this year, but it would amaze me if FIRST went to the effort of collecting this information from a team, and placing it on their website if they weren't going to be legal. Plus they (FIRST) are pushing the document on Facebook and Twitter.

Phil.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Agreed but stranger things have happened in the past. We will know in a few days.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Just a followup now that the FTC rules have been released. Rule R5(c)-26 says:

Re: [FTC]: Using Anderson Connectors for wiring.
 

Hi Phil,

We thought we would try the Anderson 30 Amp connectors. Should we buy the unassembled or the permanently bonded? Also, the FIRST components list recommends a power distribution panel. Do you know what that is?
Thank you.
Ron Pittwood
Coach
FTC 2888

Re: [FTC]: Using Anderson Connectors for wiring.
 

Ron,
There is/was a power distribution panel for FTC in the past. I have been looking for it but haven't found it yet. It simply was a power terminal that connected the battery to multiple outputs. I believe that is what is referenced.

Re: [FTC]: Using Anderson Connectors for wiring.
 

These PowerPole Splitters look interesting:

www.powerwerx.com/powerpole-power-distribution/ps-8-inline-8-way.html

www.powerwerx.com/powerpole-power-distribution/ps-4-inline-4-way.html

Re: [FTC]: Using Anderson Connectors for wiring.
 

Nice find Michael.

It appears that it is a common bus bar with power coming into any lead and being shared across all others. This is a nice way to put in future options for adding devices later. Start with the 4 bus version and then swap it out for the slightly larger 8 bus version.::safety::

Re: [FTC]: Using Anderson Connectors for wiring.
 

So, the ruling states the we can use up to 30Amp Anderson Connectors. I can't believe there is anywere near this much current running through an FTC robot. The 15 Amp connectors greatly reduce the bulk of these connectors. The contacts are universal between the 15 and 30 Amp connectors, so you can use the larger 16 gage contacts for the folded over wire and still install them in the 15 Amp connectors.

Does anyone see a reason not to use the 15 Amp connectors?

Re: [FTC]: Using Anderson Connectors for wiring.
 

Yes. You risk failing inspection, because they're arguably illegal. (What is "similar"?)

It's at least plausible that FIRST had a technical reason for mandating the higher-current connectors—maybe they were especially (perhaps inordinately) concerned about durability, for example.

And even if it's just a mistake on FIRST's part, ask about it in the Q&A forum before deciding to use the 15 A versions.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Actually, I think you are confused on the differences between the 15 and 30 amp connectors. According to this page:

http://www.powerwerx.com/anderson-po...owerpole-sets/

The 15, 30, and 45 amp connectors share the same housing, the only difference is in the contact.

The reason that FIRST specifies 30 amp connectors is probably because the battery is fused at 20 amps. It would be poor design to use a connector rated for less than the fuse on the circuit.

I hope this helps.

Re: [FTC]: Using Anderson Connectors for wiring.
 

David, I think your assessment is correct. The safety of the contact is an issue and the 15 amp contact is not the same as the 30 amp contact. The housing is the same for 15, 30 and 45 amp contacts. I also agree with Tristan, only the Q&A can make a firm answer on this point.

Re: [FTC]: Using Anderson Connectors for wiring.
 

I just want to point out this section of the Powerwerx page:

This is the information we worked with when using these connectors on our FRC robot. However as many others have said, only a Q&A post can be the final verdict.

Re: [FTC]: Using Anderson Connectors for wiring.
 

A couple of closely related questions:
- The rules say "Motor power, power and encoder wires may be extended by splicing additional lengths of wire" (R14<c>). Does anyone know if it allowed to just replace one of the wires (say, the power wire to the switch) with your own one - of course, of required AWG rating.

- The document about using PowerPole connectors specifically warns that you should NOT tin the wires. This is news to me: I have always tinned the wire end going into the screw terminals on motor controllers - it makes it so much easier to get in the hole. Any comments on this? Is there a real danger of the wire heating so much that the solder will melt?

Re: [FTC]: Using Anderson Connectors for wiring.
 

Alex,
The quoted text is part of the "R14 Part Modification" section of the manual. There should be no problem with preparing a wire(s) with appropriate connector for the power switch extension under this rule. Use the same size wire or larger for this cable.
Wires for screw type terminals, the push terminals on the FRC PD and for the Anderson Power Products should never be tinned prior to installation. By tinning, you limit the surface area of the engaged wire such that it degrades the current capability by the equivalent of several wire sizes (AWG). The resulting loss in wire size results in localized heating of the wire joint. In crimped contacts, the crimp tool may make a substandard crimp resulting in not only heating but also may result in wire pullout.

Re: [FTC]: Using Anderson Connectors for wiring.
 

I've been looking for an answer as to whether or not
it's legal to swap out the Molex battery connector
for the more reliable Anderson connectors.

We've been having this problem with our batteries.

http://www.youtube.com/watch?v=WVAjSqUN5gk

Is there a definitive answer? I've searched the FTC Q&A
forums to no success.

Thank you.

Re: [FTC]: Using Anderson Connectors for wiring.
 

<R03> s. ...... Also, the connectors on the TETRIX and MATRIX battery packs may be replaced or augmented with any compatible connector described in <R03>n above."

This means you can replace the connector on the battery, although you would have to ask the question on the forum to get an official ruling.

Just a note - remove the fuse first!

Re: [FTC]: Using Anderson Connectors for wiring.
 

It is 100% legal to replace the battery connector with the Anderson Power Pole connector.

See <03> n,o and s. This is very well stated here.
No need to ask the forum.

It was legal in 2011/12 and it is in 2012/13. We have done it both years.

It's also recommended that you build your own power wiring harness and use connectors to make it more modular.

We have also used the andderson connectors to make our motor connections more reliable. We solder short wires onto the motors and then add a connector.

The Anderson connectors are MUCH more reliable than any of the other FTC connectors becasue they incorporate a two-part contact. One part is a stainless steel leaf spring to provide contact pressure, the other part is the actual conductor contact. You can get two different contact, based on the wire size you are using. I recommend also purchasing the wire to go with the connectors. It's color coded zip wire that is very flexible and easy to use.

We purchase from http://www.powerwerx.com

And as said earlier, remove the fuse before you do it. Just cutting off the connector in one action will short the battery and blow the fuse (at best).

Re: [FTC]: Using Anderson Connectors for wiring.
 

Skate,
While I believe the rules do not provide for you to change to a different battery connector, it is possible to replace/repair the one provided. The Molex connector is not one of my favorites but it is the one provided on the battery and the charger. There are two regular failures with these connectors. The first is that the wires pull out of the crimp or break off. The only fix is to replace the connector. The second is the female pin opens with time and becomes intermittent as shown in your video. (If you look into the end of the connector you will see the "c" shaped pin) If you use a small jewelers screwdriver, inserted between the pin and the housing (on both sides of the opening), you can return the inside diameter of the female pin to it's original size. This will give maximum contact when inserting the battery connectors.
Replacement pins and housings are available from several outlets such as Digikey and other parts houses. When you buy the pins, be sure to buy the universal crimper. It costs about $50 and I think the part is WM9999-ND. This is a two step crimp but it does the job.

Re: [FTC]: Using Anderson Connectors for wiring.
 

It's a tough question.

I know that there are potential problems with tinned wire in screw terminals. My concern was always that since solder is soft, there is the potential for the solder to get compressed, which will cause the wire to loosen in the connector.

BUT I also know that without tinning it's VERY hard to get all the strands of copper into the screw terminal. And there is NOTHING worse than stray strands sticking out of the terminal. It reduces the effective gauge of the wire, and it';s a shorting hazard.

I suspect this is why the wire from the power switch/battery is already tinned.

My solution is to split the difference.

When I strip wire for the screw terminals, I strip some extra length. Then I tin just the last part of the exposed wire with minimal solder. This acts as a binder to hold the strands together. Then I snip off most of the tinned end, leaving almost bare copper wires with some internal solder for binding.

This lets us insert ALL the strands into the connector, but once in, the screw terminal is pressing down on mainly bare wire. It's a compromise. But for me, not having any stray/exposed strands is paramount.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Hi Al.

Here are the specific rules that apply here....

It seems pretty clear cut to me. Where do you see that replacing the battery connector would not be allowed.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Phil,
the part of the rule that triggered my response is the
o. Non-NXT power, motor control, servo, and encoder wires and their connectors may be extended, custom made, or COTS subject to the following constraints:

followed by:

s. Electrical components that are not specifically allowed by the rules (i.e. sensors, batteries, microprocessors, etc.) are not permitted. Motors, sensors, controllers, and any other electrical components may not be altered from their original state in ANY way unless specifically allowed by the Robot rules.

Emphasis mine. Since the battery is an NXT power device under par. o and an electrical component under par. s, I read this as no mods can be made to batteries. I did not check the FTC Q&A to see if there is any response there. That does not mean that APP connectors are the better choice, just that I believe the battery cannot be modified.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Al, I'm afraid you are giving bad advice based on incomplete information.

1) "NXT Power" means the NXT's internal battery pack, and thus not allowed to be modified. The 12V Battery is Tetrix, thus it is "Non-NXT Power" so it IS allowed to be modified acording to 'o'.

2) Apparently you are going to totally ignore the final caveat in the 's' rule that specifically states that Battery Mods are legal? It says....

I'm not sure how they could have stated it any more clearly. TETRIX battery mods are legal. Period! Why put that sentence in, if you are not allowed to modify the battery? They even refer directly back to the Andserson connector clause. This is 100% clear.

Rule S is NOT inconsistant with itself if you read the whole thing. It states that you can't change any other electrical components UNLESS it's allowed by the rules... and then it goes on to specifically allow modifying the battery connections. You can't just choose to apply some of the rule to make your point.

---

For the record, last year's rule was ambiguous about the battery connector. The rules said you could use the connectors, but couldn't change electrical components. So we asked the Q&A about the battery connector, and it was approved. This year they have added that last caveat to make it clearly legal.

And... although it doesn't prove anything more than the rule itself, the #2 robot at worlds last year used Anderson connectors on it's batteries, and it never had problems with inspections (or power). And we know all the rules have openned up since then.

I'm going to let the dead horse lie now...

Phil.

Re: [FTC]: Using Anderson Connectors for wiring.
 

Phil,
You are correct. I had forgotten the last sentence was added this year.

Re: [FTC]: Using Anderson Connectors for wiring.
 

No Problems...

Phil.

Re: [FTC]: Using Anderson Connectors for wiring.
 

We switched to an Anderson Powerpole based bus late last year and it
has proved to be quite an improvement over daisy chained power.

Thank you for the rule clarification. I had read that rule earlier in the season,
but I was looking for a rule that would allow our team to use an Arduino
to control decorative lights. I therefore was not focusing on the battery
and I missed that.

Thank you for pointing it out. We are cutting our Molex connectors off
at our next meeting.