V-TAC 42W LED TRIAC Dimmable Ceiling Light Black Round Ø50cm VT-7758-B 4000K 4400lm

VT-7758-B is a round V-TAC LED ceiling light, 50 cm across and just 6.2 cm deep, in a black housing. The manufacturer places it in its designer series — a flat disc mounted directly to the ceiling with no drop, intended for living rooms, bedrooms, hallways, offices, hotels and hospitality. The manufacturer's model number is 6911 and the EU EPREL registration is 1468853.

42 W and 4400 lm — what that really means

The fitting draws 42 W and delivers 4400 lm, an efficacy of 105 lm/W. That is a lot of light: 4400 lm is enough to light a room of roughly 20–25 m² on its own, and in a smaller room it will be distinctly bright — which is why the dimming here matters practically, not just decoratively. The distribution is omnidirectional (360°), and EPREL registers the source as non-directional, meaning it spreads flux broadly through the room rather than concentrating it in a cone.

TRIAC dimming — and what it means in practice

The luminaire has built-in TRIAC dimming (mains-side phase-cut dimming). No separate controller or control wire is needed: an ordinary LED-rated wall dimmer wired into the supply is enough. Check the dimmer's datasheet for trailing edge (RC) support — LEDs behave best with that type. A standard switch works too, but then the fitting only ever runs at full output.

Colour temperature: 4000 K, single, fixed

The fitting emits neutral white 4000 K and that is one fixed colour. Two independent manufacturer documents confirm it: V-TAC's own product listing describes it as "42W LED Designer Ceiling Light Round Black 4000K", and EPREL entry 1468853 gives the correlated colour temperature as a single value of 4000 K and explicitly declares the source not colour-tuneable. If you are looking for a 3000/4000/6500 K switchable fitting, this is not that model — 4000 K is permanent here.

Light quality — the full EPREL figures

• Colour rendering CRI: 84 — the value declared in EPREL, higher than the "80+" usually quoted in sales material.
• R9 = 0 — saturated reds are not boosted. Neutral and cool colours render correctly, but strong reds (upholstery, warm-toned wood, food) will look more muted than under a high-R9 source.
• Colour consistency SDCM 6 — a wide tolerance. If you buy several units for one room, visible differences in the shade of white between units are possible; order them together, from one batch.
• Flicker: PstLM = 1.0, stroboscopic effect SVM = 0.9 (values declared in EPREL).
• Displacement (power) factor: 0.9.
• Lumen maintenance: factor 0.96, survival factor 1.0.

Energy class F

The fitting carries energy efficiency class F. That is not a build fault: the EU scale for light sources is very demanding and class F covers everything from 85 lm/W upwards. At 105 lm/W the product sits within that band — it uses about 42 W where traditional lighting of comparable output would need several hundred.

Specification

• Manufacturer code: VT-7758-B, model 6911
• Dimensions: Ø 500 mm x 62 mm high
• Weight: 3.02 kg
• Power: 42 W
• Luminous flux: 4400 lm
• Efficacy: 105 lm/W
• Colour temperature: 4000 K (neutral white), fixed
• CRI: 84 (EPREL)
• Beam angle: 360°
• Supply: AC 220–240 V, 50/60 Hz
• Dimming: yes, TRIAC (mains phase-cut dimmer)
• Light source: integrated LED modules (not replaceable)
• Ingress protection: IP20 — dry interiors only
• Switching cycles: over 15,000
• Start-up: instant
• Certification: CE, EMC, RoHS
• Guarantee: 2 years
• EPREL number: 1468853

Things to bear in mind

The diodes are permanently integrated — at end of life the whole fitting is replaced, not a lamp. IP20 rules out shower zones and damp interiors. A 50 cm disc is a large element on a ceiling: the 6.2 cm depth works in its favour in a low room, but in a small room it is worth checking the proportion against the ceiling area.