UL states that no more than fifteen notebook computers can be charged upon one circuit simultaneously, less than one amp per computer. Bretford's laptop carts made for 18, 24 & 30 computers require two charging units, and UL recommends each electrical unit be plugged into a seperate circuit to prevent the nuisance of tripping the circuit breaker. This automatic timer allows both units to be plugged into the timer, alternating the power to the two sides so you can use just one plug. The timer is programmed for two-hour intervals but can be programmed as you wish.
