Hi everyone,
I just started my FD journey equipped with a 6384, Flycolor V3 80A, propeller from propellerking and a 8s3p copy of FDassist plus with XT 90 2+2 connector purchased in Lithuania.
I have to adapt the Xt 90 2+2 plug to my Xt 60
ISDT Q8 charger plug.
Does anyone know what is the central cable and where it is connected, maybe to the BMS ? I suppose it is the charging lead… I have no voltage on it battery disconnected.
That’s the correct assumption.
Hi,
As mentioned above this is for the BMS.
The way the battery is built at the moment charging will be done via the connector and balance will be done via BMS.
The Q8 charger you mention would need balance wires for monitoring cells which you currently don’t have on your battery.
You’d need to decide wether you modify the battery to charge via Q8, or source a charger Foil drive type for charging this.
Cheers,
Jordi
It isn’t possible to charge the battery with the Q8 without using the balance system ? I was thinking in this way
My bad! I just assumed they’d always need a balance cable, by the manual looks you’re on the right path.
You should be able to charge the battery by doing a Xt60 from the charger to a XT90 to battery and leaving the BMS cable out*positive to positive, neg to neg). This will charge the battery without balancing.
Someone more experienced can confirm but you could also put a 33.4volts source through the big positive cable and black small one and the BMS will looks after the balancing. There’s a amp limit of 8 I believe for this option.
Jordi
Would you have a link ?
Another track would be to remove the film, study the connections and put another heat shrink film (<1€)
*
And while you’re at it, on the battery side, maybe replace the XT90 with a AS150U which offers 4 micro pins: p1/2/3/4 for gnd, p1, p2, p3 to do external balancing of your 8s3p battery during charge with your ISDT Q8.
Thanks for everything,
To order a battery, PM @Pink_Foil
My adaptor lead is done for charging and it works without balancing, the Q8 charger just asked before launching the system if I will proceed to an unbalanced charge.
First test of the FauxDrive today, I will keep you in touch.
Do you intend to not use balancing or is it just for testing ?
Balancing, at least during charge, is a way to monitor your battery health.
I was thinking my BMS will do the job… I did as @Jordi said, charging by means of the BMS.
Is that right ?
It depends on the peace of mind you want to reach.
Even if voltage balancing is better for the battery during charge AND discharge, many users here have decided to balance only during charge because many fires have started off charge due to a BMS HW issue and have burnt houses, boats, vans, … in the past. Pictures are available on the forum, fortunately not recently.
When you do the time ratio, one 1.5h efoil session per week, 1.5h supervised charge time, that’s 7*24-3 = 165 hours per week where you can leave your battery unattended (in its barbecue/amo box or fireproof bag) and the fire risk is close to zero.
Here is a Molicel cell fan: 'Samsung 30q 18650 -VS- Molicel P26A 18650 (and the winner is.....) - #5 by deeproot
Tks for the warning, I’ll take care of my Molicel p42a 8s3p.
For the moment, I succeeded to charge it with my Q8 charger at a low 2.5A not to brutalise it.
First test with backpack and 35liters board tomorrow 
, first with a 120KV and if it’s not enough I’ve another 170KV 6384 motor.
Do you bypass your BMS then ?
The charging rate recommended by MOOCH based on tech sheets for Max Life / Standard / Rapid is usually 0.25 / 0.5 / 1.5 time the cell capacity. Do you know your cell reference ?
This gives a charge time of 4h / 2h / 40min whatever the battery.
If you have Samsung 40Ts, since you are 3P, it would mean 4/4 x 3 = 1x3 = 3A during 4 hours for max battery life.
MOOCH battery charge current ratings table for dozens of cells :.
I’m limited in power by the charger power supply which is only 100W so it heats up very quickly, so I charge at a slow rate of 2.5A.
It is charging through BMS.
First try this morning with 65liter board and 85cm mast and a big front wing . Fail !
speed of the motor outside water : 4000 rpm
speed of the motor inside water: 6200 rpm
Data comes from a motor wire, strange… I assumed it would go slowlier in the water.
I’m 90kg, with a 6384 120kV(50mm stator), max timing set on ESC and 8s3p battery full, I can’t stand up on the board, it doesn’t go fast enough. I managed to take a wave by prone paddling and 100% throttle + drop on bump but on flat water without paddling, impossible.
I’ll try with a 170kV.
Any advices ?
Tried a second time today with the 170kV.
Succed to standup on my 65 liters and pump with motor stopped.
As my setup is working now with my cheap 170kV 6384 (50mm stator) set at max timing on ESC
my question is:
Is it possible to optimize the system with a better quality motor like APS or Saite (56mm stator) with a lower Kv to have the same power or just a bit more and less current ?
Because for the moment, impossible to fly my 35liters board whereas from what I see on the web it’s possible with original FD.
