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💡 CALCULATOR

Calculator lighting (lumens and lux)

Calculate how many lamps are needed for room lighting according to IEC 60364 standards. Enter area, room type, and ceiling height to get the number of lamps, lumens, and line power.

⚙️ Room parameters

Illuminance standard
Wall color

📊 Result

💡
Required Luminous Flux
4,000 lm
200 lx × 20 m² × factor 1.0
🔦
Number of Lamps
4 pcs
LED 12 W · 1080 lm each
Line Power
48 W

🔌 Lighting Line

MCB
B10
CABLE
VVGng 1.5 mm²
IEC 60364 STANDARDS FOR: LIVING ROOM
Minimum
150 Lux
Recommended
200 Lux

📋 Illuminance Standards by Room Type (IEC 60364)

RoomMin, LuxRec, Lux
Living Room150200
Bedroom100150
Kitchen150250
Children's Room200300
Bathroom50100
Hallway / Entrance50100
Stairs50100
Wardrobe / Storage5075
Garage50100
Office / Study300500
Conference Room200300
Reception200300

Room Illuminance Calculation Formula

Φ = E × S × k

where: Ф — required luminous flux (Lm), E — standard illuminance (Lux) per IEC 60364, S — room area (m²), k — ceiling height factor (1.0–2.0).

Example: bedroom 15 m², ceiling 2.7 m, LED lamps 9 W (810 Lm).
Φ = 150 Lux × 15 m² × 1.0 = 2250 Lm. Number of lamps = 2250 / 810 = 3 lamps (27 W total).

The lighting calculation is based on IEC 60364 standards, which define minimum and recommended illuminance for different types of rooms.

Number of lamps = required luminous flux / luminous flux of one lamp. Luminous flux of a lamp = power (W) × efficacy (Lm/W). LED lamps have the highest efficacy — 80–100 Lm/W compared to 12 Lm/W for incandescent lamps.

Wall color significantly affects perceived brightness: dark walls absorb up to 30% of light, so such rooms require more lamps. Ceiling height also increases lighting demand due to light flux scattering.

In addition to general lighting, consider local lighting (kitchen work surface, desk) — its standards are higher: 300–500 Lux. General room lighting and local lighting are connected to different switches but can be on the same circuit.

For lighting circuits, cable 1.5 mm² with a B10 circuit breaker is recommended. Even if the total power of LED lamps in a room is only 50–100 W, a separate circuit from the panel ensures reliability and ease of maintenance. Selection of circuit breaker and cable — in our circuit breaker selection calculator.

Frequently asked questions about lighting

How many lamps are needed for a 20 m² room?
For a living room of 20 m² (standard 200 lux, ceiling 2.7 m): 4000 lumens required. Using 12W LED lamps (1080 lm each) — 4 lamps. Using 9W LED (810 lm) — 5 lamps. Total lighting line power: 48–45W, MCB B10, cable 1.5 mm².
What is the illuminance standard for kitchen and bedroom?
Per IEC 60364: kitchen — 150–250 lux (recommended 250 lux over work surface), bedroom — 100–150 lux, living room — 150–200 lux, children's room — 200–300 lux, office — 300–500 lux. Higher illuminance is needed where precise visual tasks are performed.
How does ceiling height affect the number of lamps?
The higher the ceiling, the more lamps needed: up to 2.7 m — factor 1.0 (base count), 2.7–3.0 m — ×1.2, 3.0–3.5 m — ×1.5, over 3.5 m — ×2.0. This is due to increased distance from light source to work surface and light flux dispersion.
LED vs incandescent — difference in quantity?
LED lamp efficiency ~90 lm/W, incandescent ~12 lm/W. So a 12W LED (1080 lm) replaces a 100W incandescent (1200 lm). Number of lamps is the same, but power consumption is 7–8 times less.
What MCB is needed for a lighting circuit?
For a lighting circuit with LED lamps: up to 2000W — MCB B10 with cable 1.5 mm², 2000–3500W — B16 with cable 1.5 mm² (or split into 2 circuits). Type B characteristic is recommended for lighting — lower inrush current when switching on.
How to calculate lighting for a bathroom and toilet?
For a bathroom, IEC 60364 standard — 50–100 lux general lighting. Over mirror — 300 lux (makeup, shaving). For a 5 m² bathroom (100 lux): Φ = 100 × 5 × 1.0 = 500 lm — one 7W LED lamp (630 lm) is sufficient. In the bathroom, IP rating IP44 is mandatory for all luminaires.

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