Dmx Input / Output; Pin Assignment - Major Maxi 4 PSU Manual

DMX Input / Output

The control signal (DMX) is fed through the XLR5pol. male socket. The DMX output is
a "feed through" output, which means that the DMX signal will be daisy-chained and
will also be available on the output in case of a power failure. Major PSUs are
designed to put minimum strain on the DMX signal.
Termination
If the Major PSU is the last unit in line (of DMX cabling), the DMX signal must be ter-
minated. Therefore you will find a termination switch on the unit.
If the termination switch is set to ON, the Micro PSU indicates this by the yellow LED
and the MAXI PSU by the flashing red LED.
Output / Return sockets
In order to protect the main DMX signal against negative influences caused by defec-
tive cabling, etc..., it is galvanically separated from the Colour Changer outputs via
opto-isolated coupling inside the PSU.
The outputs to the scrollers are designed as XLR4pol. sockets, which are connected
with the XLR4pol. male socket of the first Colour Changer in line via Major Power/Data
cables. Further scrollers are connected from the XLR4pol. female socket of the first
Colour Changer in line to the second one, etc...
In order to improve current feeding and DMX transmission, we always recommend to
connect a so-called return cable from the last scroller on each output back to the PSU
return socket (XLR4pol. male). This way the supply voltage will be led back again to
the Colour Changer – in parallel to the output. Via an internal termination resistor the
loop cabling is automatically terminated when connecting the return cable.
Protection
Each PSU output is internally protected. The fuse on the PCB inside the Micro PSU is
able to put itself back.
Inside the Maxi PSU you will find so-called "Pico Fuses", which are located on the
PCB. These fuses protect the PCB against damages, which might be caused by
incorrectly assigned or defective scroller cables.

Pin assignment

4 Version: 2.0, 18.11.2011