The DMX splitter is available in three standard configurations: three, five, or eleven outputs from a single DMX input. An enhanced five output splitter with miswiring and lightning protection, and a universal power supply is also available. Units with any number of inputs and outputs may be manufactured on a custom basis.
Each output of the DFD-125-TB DMX Splitter is electrically isolated from the input, and from every other output, by 2500 volt optical couplers. Each output has its own line driver and associated power supply.
The DMX splitter allows connection of DMX receivers (dimmers, color changers, moving lights, etc.) in a star configuration as opposed to a daisy chain configuration. In a star configuration, each control cable is run to a central point, in this case the splitter. In a daisy chain configuration all the devices are connected on one control cable, the output of one feeding the input of the next. It is not good practice to simply split a DMX control cable using a "wye" cable as this can cause signal corruption due to reflections. Typical uses of the splitter include splitting the control signal between stage right and stage left dimmers, running an isolated split to a string of color changers, splitting and isolating a feed to a wall outlet for temporary or rented dimmers, isolating a stack of dimmer packs from each other, etc.
Isolation of the console from the dimmers is desirable because device failure in one of the dimmers can place damaging voltages on the control cable. Without an isolator between the dimmers and the console, this voltage can cause extensive damage to the console's microprocessor circuits. With an isolator in place, damage, if any, is restricted to the isolator. Electrical storms can also induce damaging voltages on control cables. Barring a direct strike to the system, Doug Fleenor Design Isolators effectively protect against storm damage.