Can I use the LED transformer for AC or DC lights?

Our IL200.515 electronic LED transformer delivers 11.5 volts AC. It is specified for AC fixtures only and is compatible with all Integral Lighting 12vAC LED fixtures. If you purchased fixtures manufactured by companies other than Integral Lighting, please consult the manufacturer.

Can I mount the LED transformer outside without a cover?
Do fixtures dim with further distances as with magnetic transformers?