6 1mm pins would give you more current capacity then 2 1.8mm pins. According to the spec sheet that’d give you a 20A charge port I think.
But more pins means more current/less heat.
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@stratoglide and that’s why I went full xt90. No need for math, I’ll never charge at anything over 20a 
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My First 2 builds charge with xt90’s as well it was just easy and cheap.
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There is no such thing as a 10 amp DC plug especially at 50 volts. Gx16 is the go to but has to have a water tight can and fuse (60 amp) if charging at 10 amps. I use a 50 amp 12v fuse I charge at 8 amp, I tried the 20 amp use in my other build it got very warm.
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the negative solder terminal on these break off VERY easily, just soldered to the outside instead. I would rather find something better quality.
Also don’t fit the plug from @Accrobrandon’s charger GB, but mines got an XT60 now!
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They were listed as 5.5 x 2.1 in his thread… Uh oh.
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I use the gx20 connectors as my balance ports. Be careful with the metal caps. It is no fun at all getting a short in there.
I have these silicone drip tip covers for my vape, they fit in the gx20 connector perfectly and i can still use the screw on cap
I wish they would make a version with the male and female sides swapped around.
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im surprised then, i didnt test every charger naturally but did spot test/plug a few randomly to make sure we all got what we ordered.
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Yeah, I use SP-series connectors all over my ebike. The little loop that holds the cover lanyard broke off on mine, but that’s not a big issue.
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GX16 2 and 4 pins have arrived. These will very safely handle the 8 amp charger I just purchased.
I’m also interested in pulling power out this way, or at least what the capabilities are.
Could you plug into the charge port to power something externally and how is the BMS handling that current or is it pass through? We’re never going to exceed 10-15 amps here and likely far less.
If pulling power through the charge wires and BMS is a problem, I could use the 4pin with two pins dedicated to charging and two pins dedicated to a separate fused power supply with a safe 10A cont rating for both. Could easily run a TS100 with an external voltage step down regulator for example off this. Or maybe even a small air pump or other rescue tool someone may find handy.
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Depends which BMS you have specifically
You want to ideally charge at the recommended charge rate for your pack in the case of 30Q that’s 1.5amp/cell in group. So a 4P pack should ideally change at 6 amps or less they have a fast change rating of 4 amps but this will degrade cells much faster…
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My lightbar is connected through my charge port (but mine is xt90) with a pico switch
Has been working well for over a year now
My bms is wired as charge only so when my lightbar is on, I actually see it in my app. If I lock the bms, it cuts off the power that my light is pulling
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It very much depends on the BMS. Some basically behave like there’s a diode in series with the input, and flat out will not allow current to pass the other way, and some will happily source or sink current in either direction through the charge port.
On my ebike I have a 12v step-down module to provide 40W of power for running the headlight, as well as a USB PD charger and a cigarette lighter port for external accessories, since finding headlights that will tolerate 84v of input is quite difficult.
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I didn’t even think about that. Do those even exist?
Does your BMS have a P- and B-, or does it have a P-, B-, and C-?
I found one or two Chinese ones that did, but while their electronics were sufficient, their LEDs, optics, and thermals were… Disappointing.
I ended up going with an aftermarket automotive sealed low-beam projector headlamp (what a mouthful lol) and a drop-in LED replacement lightbulb to match.
84V is in a weird valley of no-parts. Go a few cells’ worth lower, and there’s tons of options for golf carts and the like. Go over about a hundred or so volts, and you can use a lot of things that are designed to run on 110VAC mains on the DC bus directly.
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The latter. Planning to use a 12S Bluetooth LLT. 20a charge only.
The connector isn’t that great for plugged in while operating. It’s pretty big. I did see a 90* version.
Moliceli lists the standard charge for the 42A as 1C or 4.2A. Even 30q charging at 1a is silly IMO. 2 or 3 amps is probably fine. We do a significant amount of wear damage in discharge too that effects capacity. Understandably staying away from the max 4A all the time yes. But we also have people with 6p 30q packs and now many 4-5p 21700 cells are who are mostly charging at 4A.
Some Fork lifts and electric pickers run at 84v, I have some forklift lights rated at 84v they are bulky but well made.
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If your BMS has C- and P-, then it’s likely (but not certain) that you can draw power from the C- port but the BMS may not be able to shut that port down in case of low battery or short circuit.
It highly depends on how your specific BMS is wired internally, though.
I would not do it from a BMS with a C- port. It’d be much better on a BMS with a shared P- port.