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Charge Amps vs. Charge Watts
This charger is rated at 6S, 6A with a 50W power limit. It is important to understand the interaction between charge current and charge watts, as the maximum charge current will go down as the voltage of the battery being charged is increased. Hence the 6A charge rating on this charger does NOT mean all battery packs up to 6S can be charged at up to 6A! The maximum charge current for a particular battery pack is determined by the max power of the charger, divided by the voltage of the battery being charged. So a 6S Lithium battery (22.2V) can only be charged at a maximum of 2.25A on this charger (50/22.2 = 2.25A). A 2S Lithum battery (7.4V) can be charged at the full 6A charge rate (as can 7.2V NiMH batteries), but a 3S Lithium battery (11.1V) can only be charged at up to 4.5A (50/11.1 = 4.50A). To determine the maximum charge rate for a particular Lithium battery cell count, use the formula below:
Max Charge Rate = 50 / (3.7 x Cell Count)