When you are looking for a power supply, use "Watts" to figure your charging capacity.
The Chargery Model S400 is a 400W power supply.
Its output voltage is adjustable from 6V (60A = 400W) to 15V (25A = 400W).
The key is that it only delivers 400W of output.
You set the S400 to output 15v to the iCharger and the iCharger converts to the proper voltage to match the LiPo pack being charged.
To charge a single 6S 5000mAh pack at 1C, you need approximately 125W.
The iCharger would deliver 5A @ 24V to the LiPo battery while it drew about 8A from the S400.
With 400W, you could charge that 6S 5000mAh pack at 15A (about 3C) @ 24v while the iCharger is drawing about 24A from the S400.
With the iCharger 308 Duo, you have two chargers in one box.
And, it is rated at 1300W (800W per channel) maximum.
If you decided to charge using both channels with one 6S 5000mAh LiPo pack on each channel at 1C, you would be using 250W.
You play around with the math and determine the max
See my recommendation in the other post - you really want to be looking at a power supply rated at around 1300W or higher for the iCharger 308 Duo.
But, keep this in mind:
Most houses are wired with 110v AC outlets with 15A breakers / fuses.
That will limit you to a maximum of 1600W in your typical garage on a dedicated circuit.
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