Cyclos can be operated at very low temperatures by exploiting their own internally generated heat. Here are some tips:

The earliest Cyclos were specified to a minimum ambient temperature (Ta) of minus 15° C (5° F). More recent Cyclos, and all current models with Osram Qti ballasts, are specified to minus 20° C (minus 4° F). However, to obtain correct operation and dimming characteristics at these ambient temperatures, luminaires need to be powered permanently - even when not in use - so that their internal temperature is maintained at or above freezing point.

  • If tubes are dimmed to zero but power is still supplied to the Cyclo, the PCB will still be powered, which should ensure normal performance down to around minus 5° C (23° F) ambient temperature.
  • If tubes are dimmed to DMX value 3, light output is close to zero but Cyclo ballasts and tubes are powered. This should provide enough heat for Cyclos to run normally down to minus 20° C (minus 4° F).
  • Cyclos run perfectly at minus 30° C (minus 22° F) in one installation in Finland, where tubes are set to full intensity when the temperature falls this low.
  • Irregular dimming when Cyclos have not been permanently powered and are started up at temperatures below freezing can be solved by warming up Cyclos with all tubes at full output for a few minutes. They can then be dimmed normally.
  • As an extra tip, if fluorescent tubes are installed vertically, the temperature at the top of the tube can be significantly higher than at the bottom. The Osram tubes fitted to Cyclos contain temperature-sensitive components at the end of the tube with the manufacturer's marking on the glass. In Cyclos that stand vertically, you can optimize performance if you install tubes with the manufacturer's marking on the glass at the top in low ambient temperatures and with this marking at the bottom in high ambient temperatures.