U23I2R1/NLDT1 U23 is a recessed diffuser flatpanel Diffuser optics, acrylic (PMMA) microprism with diffuser foil, wide-angle light distribution. Low recessed height. Dimensions: 595 mm x 595 mm x 25 mm. M600, installation as pure lay-in luminaire for modular ceilings with basic exposed TEE grid system. Flat panel diffuser for bright and uniform illumination. Luminous flux: 3250 lm, Luminous efficacy: 120 lm/W. Power: 27.0 W, DALI dimmable. Frequency: 50-60Hz AC/DC. Voltage: 220-240V. Electrical isolation class: class II. LED with very good light maintenance; at 50000 hrs the luminaire retains 90% of it's initial flux (Tq=25°C). Correlated colour temperature: 4000 K, Colour rendering ra: 80. Standard deviation colour matching satisfy 3 SDCM. Photobiological safety IEC/TR 62778: RG0. Lacquered sheet steel housing, RAL9016 - traffic white (textured). IP protection level: IP20. IK protection level: IK03. IP from below: IP44 from below. Ambient temperature: from -20°C to 35°C. Glowwire: 650°C. 5 years warranty on luminaire and driver. Certifications: CE, ENEC. Luminaire with halogen free leads. The luminaire has been developed and produced according to standard EN60598-1 in a company that is ISO9001 and ISO14001 certified.