Al–Do you have a recommendation for where to connect the return (black) wire from each of any additional high power Victors (driving CIMs)? The power distribution diagram does not seem to suggest where they would go.
Thank you Al- that is great advice!
Al-
We discovered that the blocks will take a #6 wire as well the other night. However if memory is correct a #6 wire will handle roughly 125amps. We did some research though and according to the Maxi block website the blocks are only rated for 85amps, meaning you should use only #8 wire. This is something that either a Q&A needs to be asked (Do we need to go through the Maxi block?) or teams will have to find out the hard way at their first regional (meaning the inspectors need to know).
-Mark
Jim,
See my post above, the Tips and Guidelines has been revised on the First website. Use the DIN blocks to return the 40 amp branches to the negative lead.
Al
I think the question WRT to the 40 AMP returns is that the diagram (in the power distribution diagram) shows only 3 40A returns. What if you are using 4 or more CIMs (4 2.5" and one 3")? Can the grounds be combined so that two motors share a ground terminal block or do we need to get more black blocks?
In the Guidelines ‘corrected’ diagram, they show only 2 40A returns, which makes it more confusing.
Deb
My thinking is, I may be able to provide all service without the need for the ATC 12 or 6 breaker panels, so I need to ask, since I am uncertain.
Since we will need a 2nd Maxi-Block(total 2) because we need one more 40 AMP service(total 5) Can I use those 3 currently unused circuts on the 2nd MAXI-Block for lower amp services, for example the 20amp service for the RC, a 30amp service for a different motor on a victor, ect???
Would I also need more “Black” DIN blocks as well to now tie all those to ground?
Thanks!
Michael
The DIN rail when fully assembled makes the whole block negative and the other side positive. So in effect you may connect wires to both sides for positive and or negative (see attached picture). Hope that helps
So why is it in the rules that we must use these blocks?
if you look @ team 2200’s wiring, i am now going to have to change it. Just so that i can run 2 power wires from the 120 amp breakers to the 2 Breaker Panels.
Do i have to use one for the negative side even tho i am just going from the battery to the one breaker panel?
http://www.mmrambotics.ca/pictures/13.JPG
- Bochek
Does Anyone have the 1 – 199-DR1 din rail on hand so they could give me the slot dimensions? particularly how far apart they are
Ah, yes, that clears things up.
thank you
deb
Michael,
20 amp breakers will not fit into the 40 amp Maxi blocks and you need at least one 20 amp breaker for the RC.
Adam,
Unfortunately, you do need to redo the electrical on this pictured robot. I might add that you have some rather excessive lengths on the primary wiring. Every inch of wire limits the maximum current that can be delivered to your motors. If you simply move the main breaker closer to the pump and turn the Maxi block over so that the ground termination is closer to the inside of the robot you would remove almost 5 ft. of #6 wire I bet.
You will also make inspectors very happy if you could orient the Maxi block so that the breaker labels were visible. Please insulate the battery terminals before doing anything else. Thanks.
One does not follow the other. Although the blocks may be rated for 85 Amps, the use of a larger wire does not cause any problems. You may safely use any wire up to the maximum for which the connector is rated (#6 you stated)
Using the largest wire possible has advantages, particularly in minimizing voltage drop due to ohmic losses. Of course, it does weigh more, so that’s a disadvantage that needs to be considered.
Don
Thanks Al,
I realized that myself today, when I unpacked everything and looked into the possbility and noticed immediately that the smaller breakers wouldn’t fit.(In years past we used the now defunct IFI breaker panel).
So it looks like 2 maxi-blocks, and 1 atc-6 breaker for us this season.
sigh It’s only one more pound after all. LOL!!!
Thanks again to everyone.
I see that the most common recommendation for wiring the 120 A breaker, battery, terminal blocks, etc. is 6 gauge wire. Last year however, our robot’s 6 gauge wire was hot at the end of every match, leading me to believe that ideally lower gauge wire would decrease the temperature increase of our wires, as well as decrease resistance and voltage drop.
I have not seen any rules saying we can’t use 4 gauge, and our team likely will, but does anyone here see any electrical disadvantages and possible rule violations? (The largest factor that may persuade us not to use 4 gauge is that it doesn’t fit in some of the given power supply equipment (like the new Power Terminal Strip).
Thanks in advance for the feedback =)
Chaychay,
The wire guages in the robot rules are minimums as long as you stay with the breakers specified. I have not looked closely at the specs for the terminal blocks, but larger wire may not fit those blocks.
However, if your #6 was getting hot, you had a much bigger problem. Your robot was likely running near the point at which the 120 amp circuit breaker was close to trippin. This is not an auto reset breaker, once tripped you are done. Ther are other possiblities, was the #6 from the battery to connector hot or from the connector to the main circuit breaker or was all #6 hot? In order to raise the temp on all #6, you had to be running close to stall on all motors which means you were drawing well over 200-250 amps and likely was running the battery down in one match.
Thanks for the feedback Mr. Skierkiewicz!
All the 6 gauge was hot, but the wire from the battery to the 120 amp breaker was the worst. After a hard match (hard on the drive motors) it would be hot enough that I’d say any hotter and the insulation would have become pudgy. (notes: we were using a 2006 battery, 6 gauge provided in kit for power distribution, running 4 CIM’s on drive, 1 mini-bike on shooter, and globes/fishers for ball transport through the robot…so we were indeed drawing quite a bit of energy)
We checked our robot post-season to ensure we didn’t have any loose electrical connections, (like a loose crimp head creating this abnormal current draw) and found nothing.
(I’m my journeys across the internet I found that www.robotmarketplace.com rates the Anderson Powerpole connectors we use at 50 amps. (they are blue on the the website, but the dimensions match the APP connectors that we are given. (even though we somehow get 6 gauge wire into those connectors)) - just thought that was an interesting tid-bit, I was surprised seeing as we have a 120 amp breaker right after this connector thats only rated for 50 amps.
Anyway, we’ll probably be going with 4 gauge (~1000 strand), if your interested in how it works out, or any problems we had/are having along the way, feel free to PM me 
- If anyone has any special tips for working with 4 gauge, let me know, we appreciate it very very much.
can some one tell me if there is a video on how to mount the power distribution block because these things are separated and it looks like there is a tray in the bottom am i missing a part?can i get a link to the instructional videos?
Don’t know about a video, but the drawing provided here is pretty good. The part at the bottom is called DIN Rail, and is commonly used to mount a wide variety of electrical components in industrial settings.
Jay,
The Anderson connectors are rated for 50 amps but in our application, that should be OK. The electrical system with the wire size minimums, 50 amp connector, battery, and circuit breakers, is designed so that a 2.5 minute match should not raise the temperature of any component to the point of failure. If you look up a wire table for #6, you will see a similar pattern for allowable current. The wire tables are rating current or “ampacity” for the temperature rise of the wire inside a conduit (or in free air if you find a really good table) for continuos duty. ‘Free air’ being a higher current. Since you are heating the wire in only a few minutes, you were drawing some serious currents. This is why I suggest all teams borrow or buy a current probe or ‘Amp-Clamp’ to check the current on their robot. You may have a few seconds of peak currents while starting motors but current draw should smooth out to less than 100 amps while driving. Since all the wiring was hot, you were drawing very currents all the time. This could have been due to the design choices you made for speed/torque/efficiency on each motor or you could have had some binding in the drive train or simply high friction in the beraings due to weight. Teams should always check their performance against the design criteria to be sure they are running near design parameters.
A final note: The wire heating would also conduct to the main circuit breaker so that it’s trip point would be far less than designed. Did you ever trip the main breaker?
Mr. Skierkiewicz, I do not recall the 120 A breaker ever tripping last year, I guess we were cutting it really really close.
Seeing that much of our main power distribution equipment is rated for ~50+ Amps, would there be a noticeable advantage of upgrading some of that equipment to ratings of ~120+ Amps say in a pushing duel between two robots?