Originally Posted by dirtandhoops
Since I am still new to lighting, I hesitate to give my opinions.
But I have wondered all along why the transformers have the taps up to 15 or 16 volts and don't have two or three 12v taps instead. According to Stephen, my idea apparently wasn't so stupid.
And will the transformers change in this way when LEDs become dominant?
There are occaisional projects that do require higher taps because of the large number of fixtures and/or cases where transformers can not be easily positioned close enough to the fixtures.
Let's not forget, one of the advantages of low voltage lighting is that you don't have to have any 120V lines going out into the landscape. Anytime you put a 120V line into the landscape (to mount a remote transformer) there's a risk the line could be cut or damaged - then you have a potentially fatal safety risk.
As for projects that require putting the full load on the 12 or 13-volt taps, all CAST transformers can carry the full load on any tap. If all the wires don't fit in one tap then you can use a transformer installation lug
to make it happen.
In a few months we'll be releasing a Journeymen Series 75W transfomer primarily aimed at LED systems. It's a dual-tap transformer - just 12 and 15V. 15V is an ideal tap for most LED systems since (even with some voltage loss) the fixture voltage will be within the 12 to 15V window.