I realize you're talking about just changing the settings on your "LUC 4 charger"...but I have a "general" question re: charging at 500mA rather than at 1A.
I charge my mods with a USB Charger (I mean we're only talkin' $12 for 5 Ports).
It has "Smart IC" ("automatically selects the most efficient charging current to recharge the batteries").
Early on...most of my Mods (eg. istick-30W, VV V3, etc.) had a "thin" USB cord and were capable of charging at 500mA.
My recent Mods (iStick-TC40W and Wismec Presa-40) have a "thick" USB cord and are capable of charging at 1A.
So...question...if I take one of my "thin" (500mA) USB cords...and connect it between the USB Charger and one of my 1A capable Mods...will it charge at 500mA or 1A ???
Amazon.com: PowerBot® PB5000 40W 8-Amp 5-Port Rapid Charger USB Wall/Desktop/Travel Smart Charging Station w/ Ultra High-Performance Intelligent Smart IC Technology for iPhone, iPad, Android, Samsung, Nokia, HTC, LG, Nexus, Motorola, Tablets, Camera, Smartphones, PowerBanks, Portable Chargers and More: Cell Phones & Accessories
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I ma not sure if anyone replied to this. I am no expert, but I do know that the usb port has a limited output. I am not sure what that is though. I know when I charge my Kindle using my computer's usb it warns that it will take longer because it is on a low power charger. I hope this shines a small candle flame in the dark.