We don’t discriminate between broad backs and narrow backs here. Even half watts are welcome, as long as they don’t get in the way
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Further opinion:
It’s ok to make mistakes, it’s one of the best ways to learn and progress, as long as you acknowledge what went wrong and make steps to improve.
It’s not ok to double down on a mistake out of ego. Especially when you are selling the mistake to unsuspecting customers.
As mentioned above, this concept should have been bounced around a few technical heads before being brought to market. If it was bounced around heads and still made it to market, I’d be questioning the heads involved.
I hope you’re man enough to own this as a learning experience @MoeStooge.
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With overhead residential transformers on a Y system 120/240, the secondary neurtal lug on the transformer is bonded to the Distribution Station neutral. The distro neutral gets a ground installed usually on every pole that has a transformer on it or at least a pole from one span away depending on the soil.
Every residential service drop also has its neutral tied to the distribution neutral. The case of the transformer is also tied to the distribution neutral making a return path connection for the high voltage lug. It has happened in the field a time or two where an apprentice has cut a neutral to a house before deEnergizing the service. As you know this is a receipe for magic smoke. Lose the neutral and you 240 one side of the service the other leg becomes a return path damaging all appliances wired for 120v unless load is balanced at the panel. More often then not where multiple services are hung from a transformer magic smoke doesnt happen with a neutral drop. This is where the neutral is being carried through the neighbors grounds through the panel bonding between the ground lugs and neurtal lugs, through the weatherhead and back to the transformer.
If you meter the hot leg from a panel to a panel ground rod you will get the same Volt reading as hot leg to panel neutral. Ground and neutral at the panel are at the same potential.
We install ground rods to protect equipment and people from step potential. There is an unintentiona return to source through earth ground. Electricity is lazy and will always find the shortest path back to source
For me it makes more sence to know at what potential the panel is when working it hot. If an unitententional potential is applied to equipment you are working on it is now presents an unknown hazard. Like applying a HV hot leg to an ungrounded panel, the guy who opens it will likely have a bad day.
In my line of work this would be a setup for failure.
Any of these 40 to 80v DC systems should be handled with care.
Rubber gloves. With a chassis ground if you have a fault you will know it. If you have a fault on an isolated chassis you have a trap. An unitentional setup for a bad day. Working with knowns is the way
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I’ll take that as houses are still safe and you’re firmly doubling down 
Good luck with the V6.
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A multimeter can tell you the same thing without an expensive and dangerous fire.
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I see your logic here but the difference is in where the current is being driven. Being at equal potential is not quite the same as being an intentional current carrying conductor. The intent of the ground bond at a y xfmr on a pole is to establish the ground reference voltage and prevent different legs of the y with slightly different impedances from developing offset voltages. Like im sure youve seen a bad neutral bond causing one leg in a delta - y xfmr going to 180vac then a-c showing 76vac. The bond makes a common reference but isnt intended to carry current via the EGC or the grounding conductor except in fault conditions.
The neutral or grounded conductor is to carry all of the current back to the bond at the y is intentionally the lowest shortest path. Good lazy predictable path.
At every separately derived service (for non sparkies this is a legal definition and means new build, structure, generator, or post xfmr setpnip or down) the egc (electrode grounding conductor) is bonded to the electrode and neutral/grounded conductor or high leg of a delta/delta high leg service - the high leg is also now a grounded but not a neutral conductor. You would never connect the high leg of a delta delta and use the grounding conductor as the return current path as that would be very dangerous.
Bonding the negative of the battery to the frame but using a separate current carrying conductor would provide the fault clearing safety you are describing but using the grounding path as the current carrying path is a mistake and could be dangerous imho.
You don’t have to take my advice, but you are setting some kid up for a bad day if they don’t follow the correct order of operations, or if the negative connection breaks at the battery or esc. If the negative at eh battery is open and side of the track the cover comes off to look at what’s going on holding the battery lead and touching anything is a circuit via the positive connection. If the chassis is only the ground and not the current path then there is no risk. To truly bond the chassis for safety it should be done at half voltage and it should be protected by a fuse. If it doesn’t have an ocp device then it is just a hazard and it should be isolated and isolated well.
Technically you arnt required to isolate and leave unbonded dc systems under 300vdc but that is with the caveat that the system can not expose persons to greater than 5mA of current, and 12s batteries can, when bonded to the chassis or using the chassis as a current path in normal - non fault - conditions cause this. The rules don’t say as long as you wear gloves, because people are idiots and do accidentally stupid shit. If
As electricians we are the last line to make sure system keep people safe, the fire trucks roll when you hit the button that i made work. The switch turns on the light without killing you because i made sure it was safe for you. Your breaker poped and your house didn’t catch fire because i made sure it didn’t. And when you spray the hose on cord in the driveway as your kid is vacuuming the car and he doesn’t die, i did that. And when your eskate battery takes a shit and a wire breaks, it needs to not expose users to voltage as they carry the board back to the pit.
One sweaty racer having a bad day will add another exception to the code and regulations will hammer us down into greater obscurity.
On mobile so this wi full if typos and run ons
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So… i should intentionally set my board on fire because if i dont, its an unknown hazard?
You do realize running a properly insulated negative and positive doesnt make things less safe, you could just still chose to treat the entire chassis like its still potentially live (which people should be doing regardless if they want to be safe) and now just be doubly safe. Your argument here is that by intentionally inducing a potential risk, its somehow safer because you know its dangerous… is that not incredibly counterproductive? OSHA would have a field day with that logic.
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assert your dominance, shit on the board first
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But we’ve been running battery isolated chassis’s on every esk8 ever built (including your previous boards), and that approach has been proven to work well.
You haven’t addressed the concern that you are greatly increasing the risk of shorting the pack, when you ground the negative of the battery to the chassis.
The only benefit I see is you don’t have to run a negative battery cable, and that seems a meager return for greatly increasing the risk of a battery short for the end user.
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I believe by posting that very image, that is what I have done.
If Stooge wants to stroke his ego and pursue this concept then best of luck to him. I pray for his customers.
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Maybe this is why I’ve yet to get a response on my whole debacle 
Too busy stripping half the insulation off of all the previous SRB boards to “make them safer”
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You’ll notice that even in his own thread he hasn’t actually responded to any safety concerns, just fucking rambles about houses and cars.
BRB, going to extrude a smaller cylinder out of a bigger cylinder in Fusion to get him back here.
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Be careful, if you extrude a second smaller part that sticks out of the bigger one its unethical. See example below.
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Make sure you find the step files for those cylinders from a hardware retailer
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As someone who’s not very experienced with electricity, this is what’s resonating with me.
With house appliances, the ground is exposed so that in the case of a short, the supply of electricity can be stopped almost instantly. Whether that’s a fuse, circuit breaker, GFI, or what, these devices need current going somewhere it shouldn’t in order to function, and the massive exposed ground provides that path. As soon as a short appears, the protection device does its job and stops the flow of electricity.
As far as I’m aware, the battery on a Stooge board is not fused or protected in any way, and that is the biggest difference to me. If a short occurs on these boards, you don’t have a fuse blow, or a circuit breaker or GFI trip. Instead, you have a massive, uncontrollable battery fire from a continuous short across quite large ampacity conductors.
I think that expanding the exposed surface area with the ability to provide that risk is a terrible idea. I, like many others in this thread, hope you reconsider selling boards built this way.
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Coming soon™
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Ha! I literally have almost this exact setup on a semi-modular rv solar setup I built.
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Typicaly in home wiring the Grounding electrode conductor is uninsulated for cost reasons, since there isnt supposed to be current flowing on this conductor under normal operating conditions, no need to pay for that insulation. And just to add a bit more, in a cable like romex, only the very ends 6-8" are completely uninsulated, the remaining lengh of the run has at the very least a paper wrap around that ground wire
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Some clown sells these for… prepare yourself…
$95 a piece
For use on the battery discharge line on an ebike/moto🙀
My brother in Christ, if you are popping fuses that often, this is not the solution.
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