What are Lumens versus Watts when looking at LED Lights in Comparison to Incandescent Halogen Lights
When you’re looking for LED lights, compare lumens to be sure you’re getting the amount of light, or level of brightness, you want.
Think Lumens, Not Watts
We typically buy things based on how much of it we get, right? When buying milk, we buy it by volume (gallons). So, why should light be any different? For decades, we have been buying light bulbs based on how much energy they consume (Watts) — no matter how much light they give us (Lumens).
What’s a Lumen?
Lumens measure how much light you are getting from a bulb. More lumens means it’s a brighter light; fewer lumens means it’s a dimmer light.
Lumens are to light what:
- Pounds are to bananas
- Gallons are to milk
Lumens let you buy the amount of light you want. So, when buying your new LED Lamps or Fixtures, think lumens, not watts.
The brightness, or lumen levels, of the lights you need may vary widely, so here’s a rule of thumb:
- To replace a 100-watt incandescent bulb, look for a bulb that gives you about 1600 lumens. If you want something dimmer, go for less lumens; if you prefer brighter light, look for more lumens.
- Replace a 75W bulb with an LED bulb that gives you about 1100 lumens.
- Replace a 60W bulb with an LED bulb that gives you about 800 lumens.
- Replace a 40W bulb with an LED bulb that gives you about 450 lumens.
Additional Lighting Information:
Lumens – The unit of measurement of the flow of light, or ‘luminous flux’. With light bulbs, it provides an estimate of the amount of light the bulb will produce.
| Light Output | LEDs | CFLs | Incandescent |
| Lumens | Watts | Watts | Watts |
| 450 | 4 – 5 | 8 – 12 | 40 |
| 750 – 900 | 6 – 8 | 13 – 18 | 60 |
| 1100 – 1300 | 9 – 13 | 18 – 22 | 75 – 100 |
| 1600 – 1800 | 16 – 20 | 23 – 30 | 100 |
| 2600 – 2800 | 25 – 28 | 30 – 55 | 150 |
Comparing the features of Incandescent, CFL and LED bulbs:
We typically buy things based on how much of it we get, right? When buying milk, we buy it by volume (gallons). So, why should light be any different? For decades, we have been buying light bulbs based on how much energy they consume (Watts) — no matter how much light they give us (Lumens).
| Operational Features | LEDs | CFLs | Incandescent |
| Frequent On/Off Cycling | no effect | shortens lifespan | some effect |
| Turns on instantly | yes | slight delay | yes |
| Durability | durable | fragile | fragile |
| Heat Emitted | low (3 btu’s/hr) | medium (15 btu’s/hr) | high (85 btu’s/hr) |
| Sensitivity to high temperature | some | yes | no |
| Sensitivity to low temperature | no | yes | no |
| Sensitivity to humidity | no | yes | some |
| Hazardous Materials | none | 5 mg mercury/bulb | none |
| Replacement frequency (over 50k hours) |
1 | 5 | 40+ |
| IR/UV Radiation Emitted | no | yes | yes |
What Do IP Ratings Reference when speaking about Lighting?
IP ratings are generally better the higher the number – IP is actually treated as 2 digits, the first digit specifying the protection against solid objects such as fingers, wire and tools; the second digit is protection against liquids from splash or spray.
The two-digit IP rating system was established by the International Electrotechnical Commission and is used to identify the level of protection against the ingress (entry) of foreign objects into the light enclosure.
As referenced in IEC/EN 60 529 standards – a product’s ingress protection is indicated by the two code letters IP followed by two numerals, each number then representing different forms of environmental influence. The larger the value of each digit equals the greater the level of protection.
IP Table
| First digit: Ingress of solid objects |
Second digit: Ingress of liquids |
|
| 0 | No protection | No protection |
| 1 | Protected against solid objects over 50mm e.g. hands, large tools. | Protected against vertically falling drops of water or condensation. |
| 2 | Protected against solid objects over 12.5mm e.g. hands, large tools. | Protected against falling drops of water, if the case is disposed up to 15 from vertical. |
| 3 | Protected against solid objects over 2.5mm e.g. wire, small tools. | Protected against sprays of water from any direction, even if the case is disposed up to 60 from vertical. |
| 4 | Protected against solid objects over 1.0mm e.g. wires. | Protected against splash water from any direction. |
| 5 | Limited protection against dust ingress. (no harmful deposit) | Protected against low pressure water jets from any direction. Limited ingress permitted. |
| 6 | Totally protected against dust ingress. | Protected against high pressure water jets from any direction. Limited ingress permitted. |
| 7 | N/A | Protected against short periods of immersion in water. |
| 8 | N/A | Protected against long, durable periods of immersion in water. |
For Example: IP65 rated LED flood light
The two digits represent different forms of environmental influence:
- The first digit (6) indicates protection against the ingress of dust and all other solid objects.
- The second digit (5) indicates protection against low pressure jets of water from any direction.
Glossary of Technical Lighting Terms
There are many specialist terms and principles in lighting technology, like in any other specialist area. We use specific units to specify the characteristics of light sources and light fixtures. The main terms are defined below.
Color Rendering (CRI or Ra)
Color rendering requirements vary according to the application. Natural color rendering is always the optimal option. Lower color rendering is never an advantage.
Color rendering is measured according to the light source’s color rendering properties. The most common way to indicate this is with the color rendering index (Ra). To define the Ra value, the color rendering ability of the light source in question is compared to that of a reference light source. This is done by using eight standard color samples. The fewer color discrepancies are detected, the higher the light source’s RA value. A light source with an Ra of 100 renders the colors optimally compared to the reference light. The lower the value, the lower the color rendering. The Ra value should always be specified together with the color temperature (Tf).
Examples of Ra index:
- Light bulb 100
- Halogen light bulb 100
- Daylight 100
- Full-color fluorescent tube 85
- Special full-color fluorescent tube 95
- Metal halogen bulb 85-92
- Monochrome fluorescent tube 52
- Mercury light bulb 50
- High-pressure sodium light bulb 20
The color temperature of the light from a light source is defined in comparison to a black body radiator, and is presented in a chromaticity coordinate system according to the Planck temperature curve. A light bulb with a warm tone light, for example, has a color temperature of 2,700 K. A light source resembling daylight may have a color temperature of 6,000 K. Color temperature should always be indicated with a chromaticity diagram.
The perceived light color can be described relatively well by means of the color temperature. Light color can be divided into three main color groups:
- Warm tone < 3,000 K
- White 3,300-5,000 K
- Daylight > 5,000 K
Light sources with the same light color can have different color rendering properties due to differing spectral composition.
Illuminance indicates how much light hits an illuminated surface. An illuminance of 1 lux occurs when a luminous flux of 1 lumen is evenly distributed over a surface of 1 m.
By light, we mean the electromagnetic radiation perceived by the eyes. Radiation within a wavelength range of 380-780 nanometers is perceived by our eyes as light. This range is only a very small part (spectrum) of the radiation’s actual wavelength range.
Luminance indicates how bright the eye perceives a surface or light source to be.
Luminous efficacy indicates the amount of lumen generated per watt consumed. It is also a measure of how economical a light source is.
Luminous flux means the total light radiation emitted from a light source within a person’s field of vision. Luminous flux is a measure of the power of light. In some specific cases, it can also be defined in watts (W).
A light source normally emits light with varying intensity and in several directions. The intensity in a given direction is defined as luminous intensity.
Specification Explanations
Specification |
Definition |
| Type | Defines what kind of light it is, i.e. halogen, LED, fluorescent, etc. |
| Wattage | Defines the energy consumption of the fixture |
| CRI | Important character in areas where color should be truly represented. For applications involving people, a CRI lower than 70 is not recommended. In shopping areas a CRI of 90 and higher is applicable. |
| Lumens | Responsible for the brightness in a room-the more lumens, the brighter the fixture is illuminating the space |
| Lumen per watt | Determines the efficiency of the lighting system-the higher the lm/W the better the ecological footprint of the product |
| Lumen maintenance | How fast LEDs lose their brightness compared to new products (most manufacturers refer to the time when most of the LEDs reach 70% and less of their initial lumen output) |
| Color temperature | Defines the mood or ambience in a room. Low-quality lighting fixtures have a very cool temperature as these LEDs are more efficient than warm white LED products. A color temperature higher than 6000K is not recommended for many areas. |
| Beam angle | The light is radiated into the indicated beam angle-LEDs are direct light sources with typical beam angles of 120° to 180° |
| Life hours | Defines the lifetime of a LED product. LEDs last from 50,000h up to 100,000h |
| Working voltage | High quality LED products have an integrated driver, retrofit solutions are delivered with the suitable ballast already |
| Frequency | Detail about the admitted voltage frequency |
| Power factor | Efficiency of the ballast |
| Total harmonic distortion | Describes the distortion caused by ballasts and other inductive loads of the input current on alternating current power systems |
| Operating temperature | The light source is operating under the mentioned conditions according to the manufacturer datasheet-other temperatures will cause the light source to fail or not work properly |
| IP rating | The protection of the light source, ballast and wiring against liquids and solid objects |
| Dimmable | Dimming is the change in light source brightness, mostly undertaken by smart controls |
| Dimensions | The fixture’s size, important for the definition of the mounting position and space |
| Net weight | The fixture’s weight, important for the mounting construction |
| Housing | The housing surrounds the light source and ballast-the higher the IP rating, the better protection against liquids and solid objects |
| Mounting | Possible mounting ways-mobile, table, ceiling, wall |
| Warranty | How long after purchasing the products are ensured to function properly |