@kitepoc; thanks for reminding me about connecting the minus of both battery banks for the sake of communication of the controller to the “other” ESCs! I would have forgotten.
I like your idea of connecting the controller through 2 diodes to both banks. But then the controller loses 0,7V and I think this results in too low indication of the battery charge.
@E-pusher; I agree with you making the lower cable red (for positive). But the upper cable which you have drawn does not exist. If you look closer, you see that the cable starts at the upper contact of the right switch and then disappears through the backplate to the plus of one battery bank. The same from the other switch to the other battery bank. It doesn’t go from switch to switch and doesn’t go through the two upper red (minus) terminal crosses. And the cable between the two black terminal crosses should be black and not red, because it is the minus connection (for communication ground).
So looking to myself, I should have crossed the lower cable (to get hybrid parallel) and should not have crossed the upper cable.
Question: if I would add a pushbutton with 50 ohm resistor for pre-charging the ESC’s (unfortunately 2 sets at hybrid parallel), how long does the precharge hold? Do the capacitors immediately drain when I release the pushbutton, so have to activate the main switch while still holding the pushbutton? Or do I have some seconds left to activate the main switch after I released the precharge pushbutton? Probably I should measure instead of asking here…
Remark: for Hybrid parallel configuration I would skip the positive terminal crosses and connect two ESC positive cables, with the controller positive to one side of the switch, the battery bank positive to the other side of the switch.
50 ohms is too high. I’ve been using a 22 ohm resistor for several months and I have a little bit of arcing damage inside my switch. I just ordered a 10 ohm resistor to test. My goal is to use the lowest possible resistance to better protect the main switch with an acceptable amount or arc inside the precharge switch. Basically, the resistor is only there to protect the precharge switch. If the resistance is too high the voltage drop is too much so when you flip the switch you have a surge of the remaining voltage.
The capacitors drain almost instantly so the precharge needs to be held while the switch is turned. Not sure if you’ve seen my switch design but it makes it one motion. It would be easy to add to both sides. I hope with the 10 ohm resistor that it will precharge so quick that all I have to do is turn the knob. Right now I turn the knob 20 degrees and hold it for a couple seconds before turning it the rest of the way. With the 10 ohm I probably won’t even have to think about it.
I believe E-pusher was just trying to show how he wired his which is how mine is now.
Please forgive my bad use of wire color… like I said: I ran out of Red.
Hi Kitepoc: have you built this yet? I am just at the wiring stage so considering the best option for safety, simplicity: eg whether to go hybrid parallel, fuse?, pre-charge. Thanks.
Yes I end my ePPG and have done so far 26 flights that go from 15min to 2hrs (soaring). I really love how practical it is and light and torque free.
For safety i did connect 2 motors to 1 battery 12s. (2 batt 6s in series). and each batt with fuse where you join the other batt. Also i did put voltage alarms for each batt at 3.3v so under normal use they never activate.
I mount all the 4 packs on a CF base and put rails in order to make easy to install and take out batt in order to store batt in safe place during storage and charge and also to have an ejectable battery pack in case of fire.
About pre-charge i haven’t wire it because i have to open the plates in order to work inside and need time for that, but i will do it for sure as soon as i can. Mean time i leave all the time the switchs in the on position so no damage to them and the spark jumps at the batt connectors, but not so much damage because its just two escs on one batt instead of 4.
Because i have to independent systems i also have 2 switchs, one for each system and reduced amps and spark.
Latest addition its kind of a control panel for my Cel, Gopro, amps consumption and voltage and light because of some sunset flights that i land at night at the beach. I love this and how well it works.
Also because i always fly at the beach, puting propeler protection to the lower props its a huge difference other wise they just last like 4 flights.
When i make the pre-charge modification i will eliminate also the switchs and install thermal circuit breaker, that doubles as a switch, so i have 3 functions in one. Fuse 300amps, Temp cut in case of fire and switch.
Hope i help with this new ideas.
I have attach some pictures for your reference.
and you can see my instagram @flysurfkite for some videos flying it.
