Hi to all. I'm a new user of D70. Just bought a 2nd hand dry cabinet. 21litres akaragui if not mistaken that's the brand. Not to sure how to use it. Does it have auto cut off power or i have to leave the main power on continously. Any settings that i have to take not as there is a knob inside the cabinet. Pls if there is someone who can enligthen me... tks!!