2005 Electricals or 2006?

[Billfred]

Did your team use the 2006 electrical setup from the kit, or did you order the 2005 breaker panel from IFI?

Why?

[Manoel]

Did your team use the 2006 electrical setup from the kit, or did you order the 2005 breaker panel from IFI?

Why?


2005 - best US$ 84.95 spent this season, in my opinion.

[The Lucas]

2005 breaker panel for weight
Maxi blocks weigh a ton

[Sscamatt]

2005 set-up for sure. Makes everything neater, lighter, and more reliable in my opinion.

The weight of that maxi fuse block makes me cringe.

[UngsFree]

We also used the 2005 Setup, less weight and it makes everything much cleaner in my opinion.

[chrisinmd]

Looks like 5 for 5, we used last years panel too. It's so much easier to wire up, and you can hook 6 40amp loads to it, not to say anything of the weight of the gold maxi holder.

-Chris

[Richard Wallace]

2005, for weight and layout efficiency.

Also, as an inspector I prefer 2005 because it makes wiring easier to trace.

Can anyone offer some reason(s) for using the 2006 components, other than the extra cost of purchasing the 2005 breaker panel?

[The Lucas]

Can anyone offer some reason(s) for using the 2006 components, other than the extra cost of purchasing the 2005 breaker panel?
Board space and perhaps a separate drive electrical panel. Thats all I can think of.

[Andrew Blair]

Make that 7 for 7. Makes it so much easier and neater. Separate blocks inhale audibly

[Al Skierkiewicz]

2005 because it is what I would have designed if I were doing it. The electrical runs are straightforward, minimum loss, with monitoring and good electrical input posts. The high current positions are near the input terminal. I also like the fact that ground returns are numbered to match the fuse (output) positions and there are more positions than the smaller blocks. The Maxi blocks require some fudging to get a reliable contact on #6 (folding stranded wire is not a good way to fill the hole) although the distro block is an easy way for inexperienced electrical teams to get a good return connection.

[Joe Ross]

Board space and perhaps a separate drive electrical panel. Thats all I can think of.

Board space is why we used the 2006. It turns out we lost a mechanism and we had more space then we planned, but in any case, that huge breaker panel is really hard to work around.

[sanddrag]

Large one (2005). Space, 6 40 amp circuits, weight, ease of use.

[eugenebrooks]

We used the 2005 panel, although having that ground stud on
board to use as a lift point for the robot might have been nice...

Eugene

[lukevanoort]

2005. I fought tooth and claw for it since the beginning of the season. Other team members were against it saying something about filipping it around in competition being hard.(I never did figure out what they meant) It's a good thing I "convinced" them that it was the better choice, we had to eliminate 15lbs (stupid bathroom scales in our shop said we were 10 under... next time I see them I'm going to bust out the bloody sledgehammer) at competition as it was, I'd hate to have to remove another one or two.

[Eldarion]

2005, of course. ;)

[Barry Craig]

2006 because it came with the kit. If it works, why not use it? And we never tripped a breaker or set the robot on fire. Therefore, we win. :D

[evolution]

2005. I hope FIRST sees the overwhelming preference and considers switching back next year.

[The Lucas]

2005. I hope FIRST sees the overwhelming preference and considers switching back next year.
Chief Delphi is not the best sample set. The 2006 stuff works fine for most of the teams. People who post on this thread have spent time thinking about which setup is better, something I don't think the majority of teams think about. People posting this thread also represent teams that have stricter weight budgets than most. My team takes sensors off to make weight. :D

As an inspector, I would like to see the 2005 panel in the kit. It is very easy to trace wires back to the single panel. With only 1 panel, it is less likely that teams will make mistakes or forget a piece. Many teams have problems running #6 wire for the 2006 setup, while the 2005 panel can be done with a single Anderson connector and a couple ring lugs.

Obviously, the underlying factor is cost (2005 panel is $85). I would like to see IFI make a cheaper 2007 panel without all the bells and whistles of the the 2005 version.
How many people actually use the serial breaker trip feedback?
I don't, because serial cables weigh too much :rolleyes:

[steven114]

We too use the 2005 panel without feedback for the weight/convenience/space.

[Barry Craig]

The feedback port on the 2005 model was my only argument for the panel. We already have more than enough space for more breakers on the 2006. Plus, you can just add another breaker panel if need be for meore space.

[Loki1989]

we used the 2006 setup but i would have liked to have used the 2005 setup it seem like it would be easier to wire.

we busted out the 2005 panel when we ran out of space for our fifth cim therefore taking up more space and no to actually put it

[Rickertsen2]

2005. Great investment

[Biff]

2005 never even considered all those super heavy maxi blocks and ground stud. We are even running a mini bike cim on a thirty amp breaker instead of a 40 to keep from things light and to open sooner (too much power) if balls jam the roller mech.

[Dillon Compton]

2005 breaker panel - weight, ease of wiring, cleaner layout - an all around superior solution. As soon as IFI's stock recovers, I will be purchasing a few for projects of my own, actually.

[KTorak]

2005. Best money spent for robotics components :)

[Loki1989]

what i meant was that its sitting inthere with the 2006 setup i wasnt clear enough.

[Mike Hendricks]

2005. I hope FIRST sees the overwhelming preference and considers switching back next year.

We used the 2005 one (after I bugged the student in charge of electrical to consider the options). It's much lighter, cleaner looking, easier to use .. I could go on forever.

Regarding FIRST bringing it back .. this was something I thought about and this is the conclusion I've reached (which might be wrong, but I'm willing to make a gamble on it). FIRST has always been looking for ways to cut costs in the kit. The breaker panel was gone this year, and so were the LEDs. Both are items that came from IFI. IFI is already responsible for the control system and the electronics (meaning spikes, victors, radios) .. and it leaves me under the impression that FIRST couldn't financially justify using the breaker panel (there were also stories from last year of the casing breaking open .. which is a big concern). By using the Maxi Blocks, the AB Terminal block, and the other things that IFI don't supply, it opens FIRST up to other sponsors that can provide the items at a lower cost, if any.

Now, I don't work for FIRST or IFI, so take that as an educated guess for whatever its worth. I would love to see the breaker panel come back again .. but if FIRST doesn't want to put it in the kit, at least allow it as an OTS part.

And I'm with The Lucas on this one, a "dumb" breaker panel would be awesome. The flashing light did nothing but drive us crazy after we kept tripping the fuse on our FP motor in 05.

[Biff]

The best I am hoping for is the 2005 with out all the bells internal CPU, as an available option. Should be cheaper and if you are not going to use the interface why buy it? We have enough to do for the programmer with out trying to get breaker info back from the panel. However if, as part of the (2005+) panel we could get branch currents, then I would changing my tune.

[Gary Dillard]

We used the 2005 at my request - clean, compact, light. I loved it when it came out. Didn't use the diagnostics.

I have a couple questions, however:

1) IFI instructions (and lettering on the panel) say "For optimum power distribution, the auto-resetting breakers should be installed from the lowest number to the highest number", starting with 30 Amps. Does this really make that much of a difference? Is it just the power drop due to difference in resistance because of a shorter circuit length through the board? Wouldn't I have an equal or similar increase in power drop if I had to add additional length wiring to reach the lower numbered terminals rather than taking the shortest path to the breaker board?

2) Likewise, isn't ground ground? Does it matter where on the ground panel I hook up my ground wires? Can't I hook the ground from source number 1 to any ground terminal and get the same effect?

[eugenebrooks]

I have not taken a breaker panel apart to check consistency of the design with the recommendations, but you want your high current grounds as close as possible to the ground lug, and you want your high current breakers as close as possible to the power lug, in order to minimize voltage drop for these circuits. The internal layout that you would guess from exterior layout is consistent with this.

We love this breaker panel and next year we might have time to put some of the diagnostic info on the IO display. I don't want to do a dash board, but I think that a led light when a new breaker pops and an indicator on the user led display of which one it is could be a good thing.

We used the 2005 at my request - clean, compact, light. I loved it when it came out. Didn't use the diagnostics.

I have a couple questions, however:

1) IFI instructions (and lettering on the panel) say "For optimum power distribution, the auto-resetting breakers should be installed from the lowest number to the highest number", starting with 30 Amps. Does this really make that much of a difference? Is it just the power drop due to difference in resistance because of a shorter circuit length through the board? Wouldn't I have an equal or similar increase in power drop if I had to add additional length wiring to reach the lower numbered terminals rather than taking the shortest path to the breaker board?

2) Likewise, isn't ground ground? Does it matter where on the ground panel I hook up my ground wires? Can't I hook the ground from source number 1 to any ground terminal and get the same effect?

[Al Skierkiewicz]

We used the 2005 at my request - clean, compact, light. I loved it when it came out. Didn't use the diagnostics.

I have a couple questions, however:

2) Likewise, isn't ground ground?

Gary, Gary, Gary. This isn't ground, although many people call it that (ground is what you walk on). This is the return side of the battery and should be treated just like the supply side.
I would modify the IFI statement by saying power to the RC should be from the 1 or 2 position and then follow the IFI recomendations for any additional outputs. You can visualize the current path within the box from where the input terminals are located. Since everything has some resistance, high current items will draw current through this resistance causing a voltage drop across the resistance. The high current outputs (40 amp) are above the input terminal and will drop voltage from the terminal to each output while minimally affecting the lower current outputs. Anything that draws current from the lower current outputs will also drop voltage from the input terminal to the output. That is why I recommend that the RC be powered from the position that will have the least voltage drop/closest to the input terminal. If you look at the board you will see that the return terminals are also numbered so that they roughly correspond to the current path the supply side takes to minimize loss. The RC is the most voltage sensitive device in our system, cutting out when the input voltage falls below about 8 volts. By putting the power closest to the battery inputs allows a minimal drop during current spikes and lets you play longer and harder.
As to the wire length question, the breaker panel has all robot current concentrated in one device while wiring is carrying current to individual devices. The amount of current that flows through the panel is the same current flowing through the battery and at full charge that could be well over 400 amps. Ohm's Law cuts in where V=I*R, so if you keep R constant and increase I the voltage also increases. #10 wire is .001 ohms per foot but I bet the panel is about one tenth of that or less.

[Gary Dillard]

Gary, Gary, Gary.....

Dang, a mechanical engineer trying to be an electrical engineer gets busted for his ignorance. V=I*R? I vaguely remember that from college; must have been that circuits class I slept through.

Better to keep mouth closed and be thought a fool.....

Thanks for the info guys

<note to self - have electrical team rewire robot at Palmetto>

[Gary Dillard]

Better to keep mouth closed and be thought a fool.....



<I need a bigger mouth or a smaller foot; arguing electricity with Al Skierkiewicz - Dillard's a moron (please don't make that a spotlight quote>

OK Al, I've been thinking about this and I disagree with you - I'll have to draw up a circuit diagram tomorrow if I didn't explain it well here - although your point about current spikes may be correct (remember M.E.'s think in steady state).

First item is a nit - If you look at the IFI panel, AND all of their documentation, they refer to the return side of the battery as Ground. It's marked ground 2 places on the panel, and each terminal is G-something.

Breaker Panel Reference Guide Section 3, paragraph 2: Connect Negative(-) side of the battery or Ground to the center post contact labeled GND.

Section 6, paragraph 1: The return path or Ground for these outputs are located at the bottom of the unit and are labeled G1 through G22.

Second, your point about the resistance of the panel being one tenth that of the wiring is exactly what I was referring to in my first question. If my load (motor/controller) is located on the ground side of the board (bottom left), here are the 2 extreme cases for routing:

(1) Big honking wire from battery terminal negative to ground lug, 1 inch of board from ground lug to ground blade#1, 6 inches of wire from ground blade #1 to Victor, N feet of wire to load, N feet of wire back to Victor, 4 inches of wire from Victor to Output blade #21, 6 inches of board from blade #21 to positive lug, big honking wire from positive lug to battery terminal positive.

(2) Big honking wire from battery terminal negative to ground lug, 1 inch of board from ground lug to ground blade#1, 6 inches of wire from ground blade #1 to Victor, N feet of wire to load, N feet of wire back to Victor, 8 inches of wire from Victor to Output blade #1, 2 inches of board from blade #1 to positive lug, big honking wire from positive lug to battery terminal positive.

Both are series circuits, so the total circuit resistance is simple addition. The only difference in the circuits between the 2 is trading 4 inches of wire in (2) for 4 inches of board in (1). By your numbers that's a difference of .3 milliohms, with circuit (1) - my circuit - having lower resistance. So, for a fixed voltage source (which we have) I will have more current (more power) to my load, or looking at it another way I will have an additional .027 mV in available voltage for a 30A circuit to drive my load that is taken up in by loss in your circuit.

Third - you said there are 400 Amps of current running through the board, same as the battery? What is the 120 Amp breaker for then?

Or should I just take my multimeter and go home?

[steven114]

While the main circuit breaker is rated for 120A, it takes a significant amount of time for it to trip at that current. I seem to remember someone quoting 8 seconds at 120A, 4 at 240A, etc. (although that is from memory, I'm sure there's a curve somewhere that has the exact speficiations)

[Al Skierkiewicz]

Gary,
You are right on in both of your illustrations. The one thing you are leaving out is that fact that there is other current flowing through the conductors (supply and return) on the circuit breaker panel. If you were to add two FP motors at position 1 and 3, then add a Globe to 5 and all of the solenoids to 7 and finally connected the RC power to 9, (extreme case but I have seen teams do this.) then you have the ability to max out current in stall to close to 200 amps for these loads. Taking the current through the resistance of the board on just the supply side, then the loss becomes 200 x .0005 ohms (guessing on the actual resistance) for a voltage drop of 0.1 volts. The drop is very small I know. But add to that the internal resistance of the battery (.011 ohms at full charge) current draw through the #6 (.0005ohm/ft.), current in a few Chalupa motors and the resistance in the connectors, terminals, breakers, etc. and the required 8 volts to the RC becomes an issue. After a minute or so of competition pushing, it is easy to drop the battery and added losses to the point where the RC is seeing only 8-9 volts. At that point I want every 0.1 volt of margin I can get my hands on. I make this recommendation because I want all my alliance partners to have the best power margin available.
As to the term "ground" it is unfortunate to use this term on any of our electrical system. It's use in other areas implies the the return side current flows through a nearly lossless conductor, i.e. chassis or metal common. Since it is not legal for any electrical tie to robot frame, "supply return" just seems more appropriate and descriptive. The use of "ground" has unfortunately caused many teams to ingnore the losses when troubleshooting electrical problems such as the inability to reach free speed or output power on kit motors.

[Al Skierkiewicz]

While the main circuit breaker is rated for 120A, it takes a significant amount of time for it to trip at that current. I seem to remember someone quoting 8 seconds at 120A, 4 at 240A, etc. (although that is from memory, I'm sure there's a curve somewhere that has the exact speficiations)
Steven,
The circuit breaker has an infinite trip time at 120 amps. It can sustain a 600% overcurrent for a few seconds and increasing times for current less than that. However, since this is a temperature sensitive device, combinations of current that increase the temperature also reduce the breaker trip point. A hot breaker may not be able to handle even the 120 amps, going down to 50% at 200 degrees. The data sheet is available in the FIRST documentation under Section 5 Robot specs.