Can you tell me what have you set your battery safe limits at?
I charge to 4.1v per cell, and generally ride to about 3.4v per cell. The Maytech remote shows 1 or 2 bars of battery and blinks at this point on 12s. I did have a lipo alarm connected the first few rides. but i was exhausted well before the alarms sounded. My aim is get a good number of charge cycles out of my pack and keep it withing safe limits.
The Seal 300A Opto has a setting on low batt where it reduces power, but I have never ridden long enough to reach this limit.
Because my 18650 pack is built in 3 separate packs giving 12S12P when installed, Each pack is actually 4S12P, so i use a balance charger (ISTD T8) with a parallel charge board.
Effectively charging as 4S36P. Even at a safe 0.5C charge rate, charging at 54A is quick. Im sure I could charge at 1C without taking too much from the pack. (samsung q30 cells)
The 2 HP server power supply in series gives me plenty of amps to play with and the charger and pack barley get warm.
I was charging the entire pack in about 2hrs 10 mins. to 4.1v and a good balance. I probably could charge faster safely.
I have no BMS just a 150A marine breaker and the Seal 300A´s own cutoff. To be honest, as much as I would like to know how many AMPs are used, i suspect I am well within the safe limits.
The amazing FR prop paired with the Gong L Pro wing set seems to be a great combo. Its agile, fast and can happily get on foil at 15kmph and reach speeds in excess of 37kmph. Its happy with a 95KG rider and performs just as well with a 70kg rider.
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Hi Ben, can you tell me your power when your foiling? Your batt is 1.44 kWh and you say you ride
So you have less than 1100 Watts. Cant believe that low power. We have 2.3kW.
Congrats on your built anyways! 
I have no way to measure.
1hr 20 mins was with some starts and stops and a few mins between falling and getting back on. Swapping riders from time to time. But then there was power left over. Not very scientific. But it’s a real work scenario. Does anyone foul non stop for over 1hr?
I tend to get up on foil very quick now, I believe it’s the starting off that’s the highest current draw.
I also have the gong pro L and have a 100kv flipsky with 140mm 7 pitch prop and can foil with 1100 watt. But that is a bit unstable so at 1300 watt it is good.
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Not sure how much difference the 120kv makes. But the FR prop is know to be brilliant.
I’m looking out for an AMP meter with logging.
Chime in if anyone knows of any.
I will receive it soon and can compare it
The 120kv or the FR prop?
You can try to make it via the charger. But you need to make sure to exactly know the foiling time. Maybe do a video with gopro etc and the in post you stop the time and compare with the charged Wh into the battery.
Hi.
I foil non stop for 18.5 miles at Max range speed for 1h12m, or 1h20m at Max endurance speed for 16 miles. Look at the average speed. Setup- 14s14p 30Q, no duct, 2 blade folding prop, slingshot infinity 76 wing, FR motor.
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What’s your end voltage per cell after that ride, 3.2/3.3v ish?.
I still need to build some confidence before going 9+ miles one way lol… That’s a long swim 
Hi.
Voltage alarm is set to 3.0v. I came in when the alarm went off. Because it’s 3.0v under load, when I go to charge the pack it’s always around 3.2v per cell.
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I go at 8am. I got all day to get back to shore. 
And I have a watch with built in cell phone in case I need to call for rescue!
But, yea. I did about a dozen rides before I had the confidence to do these long runs. So much fun exploring. 
I went for long rides too but there is always this anxiety of your efoil breaking down halfway haha… The joy of DIY😂
Thanks for the Info. So you need about 1670W at 25 km/h and 1340W at 20 km/h
What exactly is the “FR motor” and "FR Prop? Flipsky? Maytech?
FR stands for Flying Rodeo.
cool buid ben! starting my build very soon! how did you waterproof the motor cable entry into the mast? couldnt find this information anywhere on this forum. Thanks for the help