Re: Check your Anderson battery connectors
 

So I found this... from here
http://www.powerwerx.com/anderson-po...es-50-amp.html

We have been using both pink and red ones, any chance this is a problem? or are the pink ones specific to FRC and the below does not apply?

SB Powerpoles are Color Keyed
A unique feature of the SB Series Powerpole housings are that they are keyed to only mate with the same color housing. For example, a gray color will only connect with the same gray color SB housing. The Red color will only connect to a red colored connector, etc. The exception for SB50 is the black housing which also mates with the gray housing.

This feature can be used to color code different voltages or systems and prevent accidental connection.


Read more: http://www.powerwerx.com/anderson-po...#ixzz42zCwM2yr

The pink sb50's we have been using are really red sb50's. From what I hear Anderson had too much pink plastic and donated pink versions of their red power poles to First.

Re: Check your Anderson battery connectors
 

So you are telling me that it's really lightish-red?

Re: Check your Anderson battery connectors
 

Yup. The blue box under R36 says that the pink connectors from the KOP can mate with the red connectors.

Re: Check your Anderson battery connectors
 

Shaif,
How were you using the webcam in conjunction with WPILib?
We had one, and then two webcams, but we were just streaming them through the router, not doing anything with WPILib.
Thanks,
Martin Haeberli
(de-)mentor, FRC 3045 Gear Gremlins (formerly SWAT)

Re: Check your Anderson battery connectors
 

This should be noted too: check all of your connections! For motors and pneumatics especially.

We unbagged our competition robot and were wiring up some electrical components, when we barely spotted a wire through the gap between two CIMs that had completely come out of an Anderson connector. Even worse was that it was for one of our drive CIMs. We had played through an entire district off of three motors! Good PID is both a blessing and a curse I guess...

Similarly in 2014 we learned that pneumatic tubes should be checked for a complete fit into ther fittings/connectors. Our pneumatic catapult experienced some issues in the semifinal matches of our second district event, which caused us to lose both matches. We didn't figure out it was a pneumatic connection that was loose until it blew completely out of the fitting during our second semifinal match. If you take a sharpie and draw a line around the hose right by the connector to display where it should sit in the connector you can easily check for this issue by simply looking.

Re: Check your Anderson battery connectors
 

Great idea. Our hoses are all black which makes this a bit more difficult to spot but now we have a great reason to use a different color next time.

(If only they sold purple air hoses, to go with our team branding...)

Re: Check your Anderson battery connectors
 

Just use a silver or gold sharpie! That'll actually be easier to see than clear tubing (we have clear blue tubing) with a black sharpie.

Re: Check your Anderson battery connectors
 

Had a good one at L.A. last weekend. Team comes to the field for their match, tries turning it on in queue... NOTHING. Reset the breaker. Same result. Match almost ready to start. They plug in a battery from their partners, and the lights go on--at which point, the field staff proceeded to help them get the new battery secured and get the robot onto the field.

I never did hear what the root cause was...

Re: Check your Anderson battery connectors
 

We had an entirely different problem. Two matches in a row, our battery connector actually separated from the connector on the robot. Both times, it happened after going over the rock wall the second time.
The part that bugs me the most is that we had hours and hours of practice, and this never happened. Also, the connectors on those batteries and the one on the robot were properly constructed, and they are just as hard to pull (wiggle) apart as those on any of our other robots.

The first match, when we pulled the robot off the field, we wiggled the connector and the robot turned back on.
The second match, everyone on the drive team checked to make sure the connectors were properly seated. When we pulled the dead bot off the field, the battery connectors were at least 3/8" away from being fully seated.

Being dead for two of nine matches really sucks. Fixed by zip tying the connectors together.

Re: Check your Anderson battery connectors
 

Crooked cuts from wire cutters can exacerbate this problem, because they make it hard to fully seat the tube. Using a $7 tubing cutter from McMaster helps immensely.

Re: Check your Anderson battery connectors
 

This is a problem I first saw at TRR last August. It turns out that the issue was a broken connection at the battery terminal that was covered and being hidden by heat shrink. The #6 wires provided on the cables can work harden as they move back and forth and become brittle over time, leading to snapping the connection. Here's an example of a failing connection.

http://i.imgur.com/JRINTHW.jpg?1

I recommend inspecting these on a pretty regular basis.

Re: Check your Anderson battery connectors
 

I have been told for years that the SB50 connectors should be zip-tied together, but still don't quite agree.

If you find the connector pulling apart, SOMETHING is doing it. It won't happen spontaneously.

Your wires may be too short and/or your battery may be moving around within the robot. Both are problems that should be corrected by something other than adding a zip tie.

Someone always says "I've seen matches where the battery fell out and was dragged by the power cables across the field." If that happened, I'd rather have the connector come apart and disable the robot. You're going to get an E-stop anyway.

If zip-tying the connector makes a problem go away, you are really masking the problem. You have something wrong with the connection. The SB-50 connectors are very reliable and are designed for exactly this purpose.

That doesn't mean they can't fail, but failure is usually due to wear, mis-assembly, or abuse. You can't take them for granted. You need to check them and spot any potential problem. It all comes down to attention to detail.

The fact that they come pre-assembled doesn't mean that one can't be mis-assembled. The mating surfaces inside can be scratched and pitted by connecting things with clip leads, etc. (This is why the rules now state that battery chargers must be fitted with a matching SB-50 connector.)

Re: Check your Anderson battery connectors
 

I myself, along with the other drive team member when we put the robot on the field. Checked the connection, tugged on it, wiggled it. It was seated in there for good. We made sure it was not going to pop out like our previous match.

But then we go over a rock wall (not even at full speed if i remember correctly!) and boom, out for the whole match.

Back in the pits, we tug on it, wiggle it around, bend it, do everything possible. Drop the robot from 5 inches multiple times. Nothing! D:

Nothing like this has happened during any practice where we basically bashed the robot into defenses every which way.

Like you say, there maybe an underlying cause, but I guess we have to wait till our next regional to do further inspection. But even if we do fix the issue, definitely still going to use zip ties, can't risk it.

Re: Check your Anderson battery connectors
 

When you drop and bash your robot, you can only determine that you may have some loose connections. You will have a hard time determining which connections are bad by doing this. To find the bad connections, you really need to methodically check each and every connection point, starting from the terminals of the battery, to look for loose connections. Do not stop if you have found one loose connection. It is quite possible that you have two or more. You also have to treat the crimp of the contact in the connectors as a separate connection point to be checked apart from checking that the contacts are actually connecting. You seem to be focusing only on the battery connectors.