luminaires directly one after
the other; for more luminaires, splitter
is required
– Unidirectional: information reported
– Two-wire control line
(shielded, terminal resistance)
– Application: illumination façades (large
number lighting points, dynamic light)
Communication protocols
. However, stages
and shows became bigger and bigger.110
The Lighting Handbook
DMX: General information
DMX was developed the United States for
stage equipment 1986.
DMX: Features
– Usable data transmission rate:
250000 bit/s
– Refresh rate: times per second
– Max. Previously, the
slider settings for spotlights were converted
to analogue voltage levels between and
10 Subsequently these voltages were trans-
mitted parallel the dimmers via one
control line for each spotlight.
ALL dimming levels are then transmitted one
after the other via ONE joint control line.
This analogue dimming worked well with a
small number spotlights.
Only the positions the slider have been
converted digital values for the DMX. 512 channels (addresses) per universe
(control circuit)
– Max. The
cabling included large number parallel
1–10 control lines became too complex and
inflexible
