For maximum light output and LED life, each luminaire should be provided with between 10 to 15 volts.
Low-voltage lighting systems are typically installed using direct-burial-rated stranded cable. The most common cable used is referred to as 12/2 stranded cable. The size of cable used in wiring the lighting system is determined by the wattage load and length of cable run from the transformer to the lighting fixtures. It is very important to note that all low-voltage cable has a maximum rating. Overloading cable can create a dangerous safety hazard, so be sure to choose the proper cable for your lighting system.