This has been covered pretty well but I thought I would l
throw in a full answer I use for my students to sort of
cover the whole topic at once...
To begin with you have to always remember that while they all may have the same number, Channels, Dimmers, and Circuits are NOT the same.
Channels are numbers on the board that tell dimmers to turn on.
Dimmers are
power supply units.
Circuits are the wires that connect the lighting
instrument to the
power supply.
In most modern lighting systems, the default setup is
Channel #1, activates
Dimmer #1, which sends
power to
circuit #1. Also in modern systems designers often reprogram the light board so that
Channel #5 activates
dimmer #1 which sends
power to
dimmer #1 (this is soft patching). In older systems however,
Channel #1, activates
Dimmer #17, which sends
power to
circuit #36 (changing the relation of the
Dimmer and
Circuit numbers is hard patching).
In the last 15 years or so, the cost of dimmers has dropped quite a
bit. Because of this, newer lighting systems are "
dimmer per
circuit" which means
circuit #1 is wired directly to
dimmer #1. In the past dimmers were much more expensive than they are now and you often had far less dimmers than circuits. In these systems you had a panel that you used to patch which dimmers powered which circuits. A common
patch panel design has a slider that goes up and down for each
circuit. Every half inch or so, there is a little notch that the slider clicks into. Each click is a
dimmer. You slide each
channel up or down until they are all patched into the proper dimmers.
On newer systems we soft patch which dimmers are controlled by which
channel primarily for convenience. On old
patch panel systems, there is a huge amount of design work spent dealing with the patch and wattage load. It isn’t uncommon to find yourself in this situation: you are trying to use 16- 750
Watt and 50- 500
Watt, and 12- 1000
Watt instruments, on 40 circuits, with 12- 2.4K dimmers and 24-1.2K dimmers… hmm if I repatch the specials at
intermission I can do it.