The MOEN Power Station is specially designed for pedal board, which provide regulated DC 9V and DC 12V with maximum 800mA , two AC outlets allow those pedals (like some tube drive pedal) with unpopular power supply to be plugged in. The ground check circuit is very helpful when you want to check if the AC line is grounded well, it's very important to cancel noise and protect all the powered pedals and devices. The volume meter dynamically shows the signal. The ampere meter monitors the current consumption of all pedals . The overcurrent protection circuit will instantly shut off DC output when exception happens (for example, a reverse polarity powered pedal is mis-plugged in), it protects the pedals from damage.