While I have worked in places that don't turn off their dimmers - last time it was a surprise to me in the
circuit tested not to be live yet suddenly I felt a slight
shock. After that I had to use a
ghost light load while verifying the circuits I was working on were dead.
On the other
hand, it's been my tradition no matter where I work that goes back to school, that even in my work area, when I go home for the day, all
power goes out in the work area. This ensures that should a heat gun get it's
switch depressed or I leave on the soldering
iron, battery charger has a problem or what ever, the
power is off.
The same on
stage with the dimmers. When I was in school we had Kliegl dimmers which like many other types of
dimmer go nuts when control is removed from them. First you turn off the dimmers, than the light board and you simply do not reverse this process. Your light board turned off means the dimmers are already off.
No matter if the more modern dimmers are not effected by loosing signal or not, should something arc the data cable, it's plugged into something it should not be ect, there is no telling what your dimmers that are still on might do.
Also, since they are resorting back to a badly trimmed warmer
current to the lamps, you do still have dimming and heat from it going on, and potential in the
system. What happens if one night the fan on your
dimmer stops? In addition to your lamps having a huge amount of hours on them - even while dimmed, other parts such as the
dimmer's fan while it might be rated for constant use, will tend to wear out faster when always on.
Next what happens during a lightning storm or
power serge, or brown out? Nobody there to save the dimmers could be costly.
I know lots of places leave on their dimmers, others and I think most others do shut them down for the night when they go home. Granted most places I have been are using the smaller
portable or older technology.
I think it's a good idea to shut them down for the night. Probably much a similar debate to turning off your computer when done verses leaving it constantly on.