Question:Power Distribution Block

[RyanN]

Originally Posted by roboticsguy1988

I would agree that there could be better methods of wiring this. However rules are rules and you can still make a great looking electrical board which doesn't weigh much. We calculated ours to weigh about 11.187 pounds.

My thought on the power distribution block was along the lines of you can do the same thing with the maxi breaker block. Notice it has 3 holes on the incoming. Use one for the main read wire coming from the 120A main breaker. then use the other 2 to go to the smaller panels for the 20A and 30A breakers. However this is NOT legal according to this years rules.

I still say the IFI breaker panel was the best way to go, I am really curious as to why FIRST doesn't approve of it.

I agree with you 100% on both topics about the IFI Breaker Panel and the 3 way Maxi Fuse Block. I'm really infuriated about this because it takes up a lot of space that we don't currently have, however, as much as I hate it, I must follow the rules. I loved the IFI Breaker Panel. It made everything so easy and simple, although I am not sure of the quality of it because it felt like it was going to fall apart when we installed it in 2005. Oh well, there is always next year, I hope

[roboticsguy1988]

It makes it more real to life in a way. I mean you never know you could be forced to do something like this in an engineering job. While there may be better methods of doing it, you have to use the more complex method.

Besides this way gives new students a good challenge.

One thing i have always thought is FIRST needs to come up with ways for students to actually start learning stuff about electronics and not just a 12 volt system. The 7.2 volt charger is a good example of this, however they limited it to IFI's design, but for good reasons i suppose. Its just i think students need to start learning some of that stuff... ohms law, how to tell what size resistor you have, what kind fo circuitry you need to make to get this effect, etc.

[Chaychay]

Originally Posted by Al Skierkiewicz

You need at least 2 of the red blocks to distribute positive to the Maxi block and smaller fuse panel. Remember, only one #6 wire per terminal.

Would it be safe to have just one #6 wire coming out of the power distribution block, into the maxi, and then from the maxi to the ATC panel? (because the maxi has an output for #6)

My guess is that this is not the preferable wiring solution as each "piece" of these power dist. blocks aren't rated for really high current, so it would be better to pass some of the current through another "piece" of the block.

Thanks for the help!

[Al Skierkiewicz]

Originally Posted by Chaychay

Would it be safe to have just one #6 wire coming out of the power distribution block, into the maxi, and then from the maxi to the ATC panel? (because the maxi has an output for #6)

My guess is that this is not the preferable wiring solution as each "piece" of these power dist. blocks aren't rated for really high current, so it would be better to pass some of the current through another "piece" of the block.

Thanks for the help!

There are a few problems here. One is that the four position Maxi has provisions for #2 to #8 wire and that leaves a lot of excess room when you terminate the #6. (It can actually fit more than three #6 wires in the same hole.) All the robot current flows through the first #6 in your question and that will produce a significant drop across even a small piece of wire. Assuming you have about 4 feet of #6 (red and black combined) and you are using 4 Chalupas, at stall the voltage drop could reach 0.8 volts or higher just in the wire. By the time you get around to feeding the RC the voltage may have fallen another 0.5 volts. Since the RC starts to get unhappy at 8 volts, you are starting out the match at 10.5 volts with a fully charged battery under high current demands. The Rockwell blocks are rated at 85 amps continuous current so they can handle high currents for short periods of time like a two minute match. Please watch for heating in the jumper accessory though, it is unrated.

[roboticsguy1988]

Originally Posted by Chaychay

Would it be safe to have just one #6 wire coming out of the power distribution block, into the maxi, and then from the maxi to the ATC panel? (because the maxi has an output for #6)

My guess is that this is not the preferable wiring solution as each "piece" of these power dist. blocks aren't rated for really high current, so it would be better to pass some of the current through another "piece" of the block.

Thanks for the help!

Besides i believe that would violate the rules... because you would not be wiring it according to the wiring diagram

[MrForbes]

Originally Posted by Al Skierkiewicz

Please watch for heating in the jumper accessory though, it is unrated.

Sounds like you have given up on trying to get usefull info about the jumper....can't say I blame you....

[Sicilianprincez]

I'm having the same problem. We have all the red and gray sections of the power distribution block, and the yellow connector to connect adjacent parts, but we feel like something is missing. How do we hold them together like in the diagram? Are they suppose to be mounted on something? Are we missing a part? Please help.

[Darkforces]

you mount them to the din rail that came in the kit. I think its an inch and a half wide and 19 inches long.

[Al Skierkiewicz]

Originally Posted by Sicilianprincez

I'm having the same problem. We have all the red and gray sections of the power distribution block, and the yellow connector to connect adjacent parts, but we feel like something is missing. How do we hold them together like in the diagram? Are they suppose to be mounted on something? Are we missing a part? Please help.

The First website has a nice blowup pdf that shows all. You can find it at http://www2.usfirst.org/2007comp_173...Strip%20R3.pdf
The rail can be cut down to size for your needs.

[tradle]

Anyone know if the grey center divider blocks (or for that matter the gray panels) are required between the red and black? For a 12V system this seems to be overkill to me.

[tradle]

To clarify even further. If you orient the blocks correctly the black and red blocks are technically isolated between each other by the wall of the red (or black) block itself. There also is a decent air gap on both sides of the wall, which is easily enough insulation between the terminals.

In the power distribution diagram it appears that there are both panels and blocks used. In between the red and black blocks are both a grey panel and a grey block on the "exposed" side. And also at the far end of the block where it would be "exposed" if the grey mounting block were not there.

So what is required?

[Al Skierkiewicz]

T,
I am recommending that teams assemble the blocks just as shown. The additional grey (thin) spacers give an extra added buffer between sections in a system that moves around. Just insurance I admit. They are needed when the blocks are used at rated voltages (110-240) for insulation. The grey locking blocks are the same kind of thing. Just extra insurance that the whole assembly doesn't slip and slide around on the rail.

[aksimhal]

Another Question: Is there a better way to attach the 6 gauge battery connector cable that just sticking it into the power distribution block, and tightning it with a screw?

Thanks,

[Al Skierkiewicz]

Anish,
That is the only way. If you strip about 3/8" of insulation and make sure the wires are twisted tight, you should have no problem inserting the cable. Make sure that you are not clamping down on the insulation. I may work for a while but the wire is guaranteed to loosen and fall out if you do.

[Bob Steele]

Al and anyone else...
We were told that there was an issue with these blocks at the PNW regional.
That they were supposed to be used with some type of ferrules that were not provided. This apparently was an issue because wires had a tendancy to slip out of the blocks....

Do you have any information regarding this? Or perhaps a place for us to buy these elusive ferrules to use with the blocks?

thanks
R. Steele