craneplaneguy
10 kW
The job of we consumers is to provide the supplier with feedback on a product, this includes finding ways to screw up the product that may seem highly unlikely to the supplier! Today I was hanging my battery bag off and on the airplane, cogitating over how and where to hang it. At one point (and here is the unlikely part, but it happened) a scrap of aluminum on the workbench made ever so brief contact with the XT-60 plug coming out of the battery for connection to the charger. The charger input cables flopped over just right when I set it down, highly unlikely but it happened . No real drama, just more then enough (small) spark to get my attention, no harm done near as I can tell, (one of the plugs got slightly eroded, but there is more then enough left for the 3 amps I'll be running through it) except.....though the voltmeter wasn't plugged in at the time, it no longer works. Hopefully the BMS was not damaged. Earlier, in fact the very first time I eyeballed the battery after receiving it, I checked out the main output wire's XT-90 plug ends, and as expected they are arranged so that the "innie" is the hot and the "outie" is the fitting going to the motor. Meaning that when packing the battery around you are not going to short it out accidentally. I assumed the same for the charger input, my bad. While the ends aren't really an outie they are, as I find out, MUCH more easily capable of being shorted. Though they don't protrude past the plastic end, there is NO plastic divider between the - and + plug ends.
So, if a small metallic item gets in there
Looking at the end that came with my recently purchased charger from Luna, it's end is much more protected, call it the innie, with a plastic divider, in other words, a much more protective screw up proof way to make these connection would be to swap the XT-60 ends, have the charger be more exposed as it were, (so what, it's fused and is only 3 or 5 amps) instead of the charger cabling going direct to the battery (and here I need to admit I have no idea if there is a fuse in there, maybe I blew it and that's why the voltmeter doesn't work anymore, beats me, I'll ask Luna tomorrow). Like I said, highly unlikely that someone would do what I did, but I can't see any reason why swapping the plugs around would NOT make a more idiot proof setup. Anytime something can be made better with no expense or weight gain, it's worth bringing attention to it. I work with very large batteries often, I'm talking 1200 lb. (and up) off grid solar deep cycle cells, so I feel especially chagrined that I let this happen, I just assumed it was more idiot proof then it was, like the XT-90 main ends are, I'll be interested to hear why mine was setup the way it was. If I had received the XT-60 ends separate/uninstalled, there is no question I would have wired them different then Luna did. Having some additional non conductive protection for the ends is obvious, but hardly needed with a change of the connector ends.
So, if a small metallic item gets in there
