Restricted to the Anderson Connectors in the Kit?

Technical Electrical
1

My take on rule <R48> is that we are not allowed to use battery connectors other than provided in the kit. Why is this? In the past we have been able to use different (better) powerpole model conectors. The ones in the kit are only rated for 50 amps and we can pull way more than that through the breaker and we have seen these things melt/weld themselves together especially after they get scratched by using the aligator clips on the chargers. Why “must” we use these? Also, the 6 gauge wire on them is not very good.

2

Sanddrag,

The Anderson connectors were also required in 2004.

For some reasoning behind why it is OK, please refer to this post:

http://www.chiefdelphi.com/forums/showpost.php?p=221200&postcount=20

in this thread:

http://www.chiefdelphi.com/forums/showthread.php?t=24890

Thanks,

Aidan

3

Is it still legal to use two connectors in parallel, for increased capacity and failure resistance?

Thanks,

4

You would have to ask FIRST that question on the FIRST Q&A

5

I asked Dave Lavery this same question at kickoff… his reply was something like this:
[paraphrase]
Those Connectors can handle 120amps for short periods of time… (i assume he meant about a match length)

The problem was when people were using aligator clamps to connect to the amp connector and scratching the mating surfaces, which was causing a poor connection and the ‘connector failure’.

You may not use alternatives, especially because of the modified weighting rule this year. (120lbs + battery and leads).
[/paraphrase]

I also, about 2 years ago asked about the 6awg wire. Yes the voltage drop per foot isn’t ideal as good as say 4awg…but apparently the insulation is rated for that current. (That is, insulation on wires has a temperature rating before it melts…) You can read about it on belden’s web site…
So the real issue here is: Is the 6awg wire in the kit have insulation rated
for 120A? (To which I don’t have an answer.)
Also I believe FIRST relies on the fact that matches are short and most teams don’t draw 60A continuous.

I’m still uncomforatable with it, I’m big on following ratings for electrical supplies based on the worst case situation and not on the usual happenings.
I don’t write the rules, I just complain about them… :wink:

6

We use identical connectors from Wrangler Power products,
http://www.wranglernw.com, the color and stamping on the parts
is the same as the Anderson product. We use 6 gauge rubber
insulated welding wire from the same source, for its flexibility.

Use the 10-12 gauge terminals to put the same connectors
on your battery chargers. This is a very safe, fool proof,
connection that will avoid scratching the contacts.

Part numbers are:
Red Connector Housing: 34-319R
Crimp Terminals for 6 gauge wire: 34-319-10
Crimp Terminals for 12-10 gauge wire: 34-319-6

Suitable adhesive lined heat shrink, by the foot
Black 3/8" 32-660B
Red 3/8" 32-660R

It is the crimp tooling that costs money:
HexJr Crimper: 38-101J (expensive, but a professional job)
Hammer Style Crimper: 38-101

The real problem this year is the explicit rule to use the
SLC-70 “screw tightened” terminals. Wrangler has very
excellent heavy duty solid copper lugs that are crimped
by the same crimpers listed above, and it would be nice
if FIRST allows us to “not build down to the electrical code”
so to speak. I understand that the SLC-70 connectors,
suitably soldered, are the best option for a team that does
not want to invest in proper crimper tooling and lugs, but
teams should have the option of doing the connections
better and safer.

7

Someone else asked at kickoff if we could use a SB120, PP175 or something else, and was told no, for the same reason as above (weight). Dissapointing, but we’ll deal. As I read the rules, we must use #6 wire. Does anyone know of a source of high stand (like 500 or greater strands) 6 gauge wire? There is lots of 4 gauge out there from the caraudio industry, but the highest strand count 6 gaue I have been able to find is about 250 strands. Better than the 50 strand stuff that comes in the kit, but I would still like something more flexable.

I saw someone posted on the Q&A about not using the ring terminals that come in the kit on the batter, and hope FIRST allows us to use others instead.

BTW, www.powerwerx.com is another source of Anderson PP and SB series connectors.

8

I think some of the rules are restricting teams who know how to to a good quality nice electrical job.

9

Electrical is often hard for many teams. I’ve seen robots show up at a regional
with the pump wired straight to the pressure switch.
FIRST is trying to eliminate confusion here as well as standardize some
robot characteristics.

10

As Aidan pointed out above, the Anderson connector was required for 2004. Although I have seen teams burn and melt this connector, they were few and far between. They do require proper care and feeding. Do not use alligator clips to connect the battery charger to them. Buy another connector and add it to the leads on your chargers. (watch for polarity, the connectors are marked.) Keep them clean, dirt and other abrasives can damage as much as gator clips. Check for proper insertion and mating. Bent contacts will not give the low resistance needed for high current applications. And here is the biggy…design your robot for efficient electrical usage. It is not necessary to draw 200 amps to move a robot through a two minute match. Rule of thumb is you robot should be able to compete for three matches without a battery change.

11

May we use the same exact model housing/contact but a different color and our own high quality 6 guage wire?

12

they talk about 6wg but id like to use SUPER 4 gauge wire, is that possible? and jsut replace the leads and use the same housing

13

Here is the way I interpret this rule…
<R48> The ES-18-12 Battery, the Main 120 Amp Circuit Breaker, and the IFI CB/Distribution panel must be connected as shown in the diagram. The ES-18-12 Battery must use the Anderson Connector and the copper SLU-70 lugs provided in the Terminal Supply Bag. The Battery terminals and the SLU-70 lugs must be insulated with shrink tubing and/or electrical tape. You may use additional lengths of #6 red and #6 black wire to reach the panel as needed to make the above connections. The circuit breaker must be readily accessible for inspection and testing at each competition event.

The #6 and the red Anderson connector provided must be used. Elsewhere in the rules, wire minimum sizes are specified, but no additional reference is made to #6. Simple answer is use what is provided. The tradeoff for lower resistance/higher weight is not significant to warrant the change. (The wire length should be too short to matter.)
I would like to know what “high quality” #6 wire is?

14

I originally interpreted the rule the same way you did, but for the heck of it asked on the Q&A, and their answer sort of surprised me:
ID: 1167 Section: 5.3.5 Status: Answered Date Answered: 1/17/2005
Q: In reference to rule R48, can we use wire larger than #6 (such as #4) diameter between the battery and the Anderson connector and between the Anderson and the breaker panel?
A: Yes

Specifically that I said on the battery side also. On the other hand, the Anderson’s are only designed for 6 gauge, not for 4. Tomorrow I’m going to try using some 4 gauge with some extra contacts I have.

Edit: Fixed spelling, stupid 8 AM classes.

15

Interesting answer. Go figure!

16

highly suprising, tell us soon wut u find so i can go out and buy the cables tonight and use it

hmmms tho just to be clear does it mean we can replace alll 6 awg wires with our own stuff? just the leads to the batteries? or can it be used at the PDB and 120 Breaker and robot battery leads?