The family owned company celduc® relais has been operating in Sorbiers, France since 1964 and has become a world specialist in Solid State Relays (SSR). Thanks to its 50 years of experience, celduc® relais offers a wide range of products to switch various loads such as industrial heaters in temperature control systems, lighting control, motor control etc.

celduc® relais creates revolutionary products such as their SU, SUL and SUM optional modules directly pluggable on Solid State Relays, or their current monitoring module called ESUC.

Okpac® SO SERIES (SSR)


  • All Celduc SSR's (Solid State Relays) are fitted with back-to-back thyristors and employ 4th generation TMS² technology with a very long lifetime expectancy.
  • Pluggable control terminals
  • IP20 terminal protection cover (removable)
  • EMC compatible for industrial environment
  • Regulated input current
  • Control status LED indication

Celpac® SU SERIES (SSR)


  • All Celduc SSR's (Solid State Relays) are fitted with back-to-back thyristors and employ 4th generation TMS² technology with a very long lifetime expectancy.
  • Cost-effective, reliable and compact solution (22.5mm pitch SSR solution)
  • Mounting configuration compatible with all standard hockey puck style relays
  • Three phase zero cross solid state relays

Sightpac SERIES (SSR)


  • This range is designed for controlling three phase loads connected in delta or delta (if balanced).
  • Compact design - 45mm wide version
  • Control status LED indication
  • Three phase zero-cross solid state relays
  • Two of the three phases are switched by the SSR, the third being directly connected