12-01-2007 11:00

MrForbes

Re: pic: 931 Preliminary Electrical Layout

Nice, thanks for letting us see what it looks like. Lotsa stuff on there!

The negative terminal post in the top right corner of the picture is not show on the 2007 Robot Power Distribution Diagram, and does not appear to be from the KOP. It also seems to defeat the purpose of the black Power Distribution Block (whatever that purpose might be). Are you sure it's allowed by the rules?

12-01-2007 12:18

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

Well spotted.

The 3/8" stud you see was a KoP item in previous years, and would be considered a COTS COMPONENT now. As such we will need to account for its cost in our materials list, and make sure that it complies with <R63> since, as an electrical conductor, it might be considered a custom circuit.

EDIT: of course under <R47> the stud is an additional electrical component, and as such would not be allowed if it is not COTS.

EDIT: Post Count = Team Number.

12-01-2007 12:50

MrForbes

Re: pic: 931 Preliminary Electrical Layout

<R57> does not seem to specifically address the negative power distribution, but from the specifics of the positive power distribution description, I would feel much safer about passing inspection by using only the new power distribution blocks and fuse panels for all intermediate connections.

12-01-2007 17:32

Mike AA

Re: pic: 931 Preliminary Electrical Layout

I honestly think that you could simplify your wiring and lose some weight if you moved the din rail closer to the radio and got rid of the stud and crimps. Thus causing one less location for something to come loose. Or better yet use the Negative posts on the smaller breaker panel. Or, I'm not sure if its required to use the din rail but you could totally eliminate the din rail and run the negative to the stud and the positives through the maxi-block.

Just a thought. I dont plan to use additional items.

-Mike

12-01-2007 17:42

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

Thanks for the weight saving idea. We do plan to compress the layout after some other chassis decisions are finalized, and we may lose the stud at that point.

However, I am pretty sure the DIN Block is required per <R57>.

EDIT: also I am pretty sure that wiring 40A circuit returns to the smaller breaker panel is not allowed.

12-01-2007 19:57

clydefrog88

Re: pic: 931 Preliminary Electrical Layout

are you using the plywood for your final board? we've saved a lot of weight in the past few years by using 1 or 2ply of hand laid fiberglass on both sides of a balsa core. it weighs almost nothing and is strong enough for a electronics board.

12-01-2007 20:20

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

That sounds cool.

We have not used plywood for the electrical system board in previous years and probably won't this year either. Usually we have laser-cut 0.22" thick acrylic sheet. Wood is nice and forgiving though, and will let us experiment with layout ideas until we feel comfortable.

A factor to consider is that the kitbot frame needs some stiffening anyway, so our choice for final electrical board material may be based partly on overall robot strength requirements, not just being "strong enough for an electrical system". Sometimes adding weight to one subsystem lets you take even more weight out of another.

13-01-2007 15:25

xghost

Re: pic: 931 Preliminary Electrical Layout

The connectors on those speed controllers(red/black)...They seem very nice...look like mini battery connectors and easier than two quick disconnects terminals. Where did you get those?

13-01-2007 18:31

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

Those are Anderson Power Pole connectors in the 15/45 Ampere size as shown here. You can get them through several distributors. A low cost crimping tool for their terminals is available at West Mountain Radio.

Good luck this season.

30-01-2007 04:39

Darkswordsmith

Re: pic: 931 Preliminary Electrical Layout

I'm still not sure whether we can use the negative stud in power distribution. Can anyone give a definite answer?

30-01-2007 06:39

Jeremytice

Re: pic: 931 Preliminary Electrical Layout

That electrical layout looks very nice you guys. Great job!

30-01-2007 08:10

Al Skierkiewicz

Re: pic: 931 Preliminary Electrical Layout

Richard,
Looks really cool, nice job! I would eliminate the ground stud and return the negative leads directly to the distro block. You save some weight in #6 and crimp on connectors and lower the series resistance, not to mention a single point failure if the stud hardware loosens.
How do you like the crimper and the Power Poles so far? We add a touch of solder to the connector just to be sure, before assembly. They crimp on the #12 Chalupa leads OK as well, but again a touch of solder just to be sure.

30-01-2007 11:36

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

Thanks, Al.

We will probably lose the stud when we compact the layout somewhat -- right now the footprint is still too large. I agree the stud takes up valuable space and is an extra failure point.

Also, I am not sure that the stud is a COTS component. It was in an old (2003? '04?) KoP but I don't think it was custom made for FIRST. Anyway I would need to get a part number and price to show for material cost analysis if we want to use it on the robot.

30-01-2007 13:11

Al Skierkiewicz

Re: pic: 931 Preliminary Electrical Layout

Richard,
It seems to me that they were available from Terminal Supply that year.

30-01-2007 14:02

Richard Wallace

Re: pic: 931 Preliminary Electrical Layout

I recall the same. I did find the 2004 Power Distribution Diagram that shows the stud. Didn't find it at www.terminalsupply.com.

But it does seem to be available at Hot Rod Wires.