1 Channel 500W DALI Dimmer


The DDC455, 500W Thyristor dimmer (leading edge) is a fully DALI compatible lamp interface unit for use in a DALI lighting control system. The dimmer is a DIN rail mounted unit that can control a maximum of 500W. It can be connected to mains voltage lamps directly or to low voltage lamps via a wire wound transformer. The dimmer is provided with a status LED and a physical selection switch. The LED provides status and fault indications, the physical selection switch is used to identify the device during system configuration.

The DDC455 does not include a DALI power supply and one must be incorporated elsewhere in the system.

Key Features

  • Out of the box operation. No programming required when using DDC sliders, rotary or push button panels
  • Input voltage and frequency compensation ensures stable output levels with fluctuating incoming mains levels
  • Over current and over temperature protection
  • DIN rail mounted and only 35mm wide

Additional Functions

The following functions may be programmed using the Helvar Designer software.

  • Max/Min levels, Fade times*, Scenes* and Groups*
  • Dimmer status report
  • System failure level/ignore
  • Power on level
  • Power on to last level

* These functions are programmable using infrared remote control.

Order Code

  • DDC455


  • Single DALI Network Router
  • Twin DALI Network DALI Router
  • Twin DALI Network Router with DMX and S-DIM


DDC455 Dimensions
90 35 58

Installation Notes

  • The dimmer is for use with incandescent lamps and low voltage lamps via wire-wound transformers. It is suitable for use with electronic transformers, if use is approved by the transformer manufacturer
  • The external mains supply must be protected
  • It is recommended that a 4A MCB is used
  • All cabling must be 230V mains rated


DALI ConnectionsRemovable connectors with paried terminals
0.5mm²–1.5mm² stranded or solid core
Mainsup to 4mm² solid core or up to 2.5mm² stranded
Mains Supply220–240V AC 50–60Hz
Heat Dissipation3.5W with maximum load (resistive)
DALI Consumption2mA
Ambient Temperature0°C to 40°C
Storage Temperature-10°C to 70°C
Relative Humidity90% max, non-condensing
HousingDIN rail case 35mm wide 2U
IP RatingIP30 (IP00 at connections)
Compliance and Standards
EMC EmissionsEN 55015
EMC ImmunityEN 61547
SafetyEN 60950


DDC455 Wiring Diagram