Be certain that your electrician thoroughly understands and applies {1999} NEC Articles 640, 530 and 250 and the components served from transformer-isolated sources in 640-7(b.), 530-70, -71, -72, -73, 250-146(d) and 410-56(c).
The NEC derfines this 60/120V source as technical power. There is the potential for some serious abuse with all the currently advertised so-called “balanced-power” isolation transformers furnished with NEMA 5-15 or 5-20 receptacles, that seem to contradict 530-73(a)(4) All 125-volt receptacles used for 60/120-volt technical power shall be uniquely configured and identified for use with this class of system. Don’t overlook acceptable grounding methods for the center tap of the isolation transformer.
Also, anticipate that triac-based light dimmers can very effectively interfere with audio signals.
[This message has been edited by Bjarney (edited 04-07-2003).]
