okay, so thats not my diagram, and now i think it has switched/unswitched backwards. Especially if ya use the definition of "Unswitched power describes power that is always on while switched power refers to power that can be turned off and on". Lets move past terminology and look at pics
Here's one of my modded batteries, power is on the left. Meaning, direct power to the aircraft even if dji battery not powered on.
That left side connects directly to the power lead which goes into the phantom, essentially bypassing the smartboard. It sends current into the smartboard, like it was charging. But, the power cannot come "back" through the line - i've never had the DJI battery charge the externals, i think the smart board prevents that in some way? There are cases where the externals may charge the stock battery, i just let it do its thing, turn it all off and then restart and its good.
In this thread, I've read that folks have done both and found that the side shown in my pic above worked best (unless you are wanting to remove the dji battery cells and hookup the smartboard to externals). And, it has benefits .. if the DJI battery runs out of juice, you can continue to fly on the externals; that is, the aircraft is able to still fly and stay connected to the RC running only off the external batteries, despite the stock battery being dead. You may see a "battery error" in DJI go, but all connectivity will stay. If you run the power leads on the other spot, as soon as the stock battery goes dead, you lose power from the externals, it cuts it off. I've found my externals always have 5-7% mah left, even if i land at 0/1%, so i see that as some 'reserves' which i can use if really have to. I've flown for 2min in this state before. It wasn't fun, but the phantom came back to me
hi, and thanks for elaborating and pics.
so the dji battery cells main leads go to the UNSWITCHED connections of the smartboard,
and if the dji bat is SWITCHED on, the power that now can go through it, comes out at the SWITCHED side (hence the name) and goes to the bat plug, which plugged wheter to the copter or the charger.
- if the dji bat is switched on and is in the copter, the power goes from the dji bat cells to the UNSWITCHED SIDE, then through the smartboard come out at the SWITCHED SIDE, go to the bat plug and from there to the copter mainboard and is used.
- if the dji bat is connected to the charger, the power goes from the charger to the bat plug which is directly connected to the SWITCHED SIDE (no matter if the batt is switched on or off) of the smartboard,
an through the smartboard, which regulates charging voltage and current, to the UNSWITCHED SIDE, from there to the dji bat cells. (maybe also through the balance leads)
- if the externals bat main leads are connected to the UNSWITCHED SIDE of the smartboard, the externals are like an extension of the dji cells,
but this does not work well because the smartboard only lets through
a certain amount of mah, so this is not recommended.
(it might be resetted by disconnecting the dji cells balance cables, some button long press magic etc.
one user a few months ago mentioned he found a way but wanted to test it further, but nothing followed, why is there made a mystery of this things??)
- if the external main leads are connected to the SWITCHED SIDE of the smartboard, their power goes directly to the dji bat plug and from there to the copter, and just adds the mah to the dji mah,
which works good,
(except the littles issue with the dji bat going to charging mode,
which can easily be resolved by bringing the externals to 0,1-0,2 volts less thang the dji batt BEFORE putting the dji bat into the copter and connecting the externals, for example with a halogen-discharger+voltmeter,
or taking off quickly after connecting the externals, i tried both with sucess)
but the question is,
you say the externals bat main leads in your horizon mod are connected to
the SWITCHED SIDE of the dji bat,
where also the dji charger is DIRECTLY connected,
so the charger and the externals are directly connected,
and they can be charged this way, and it seems to work, but
WHY DO THE EXTERNALS NOT EXPLODE AFTER SOME CHARGING TIME?
because the dji charger is, afaik, a simple constant voltage power brick.
the balance leads can not prevent that current flow.
(next problem: if you connect the balance leads from the dji batt to the externals balance connector
while the externals are empty and the dji bat is full or the other way around,
the cells of the fuller bat will immediately start "charging" the cells ot the emptier one
through the balance leads without any electronics with an extreme current, only limited by the wire resistance, so you are not supposed to do that, or what?)
do i missunderstand any terminology, isnt it true that
the SWITCHED SIDE of the smartboard solder joints is directly connected,
without any electronics in between, to the dji bat plug ?
is there a tiny diode somewhere?
