light fastness, sun simulation
Solar Simulation

Sun Simulation – Advanced UV & Weathering Testing Solutions

Solar simulation is used to determine the aging behavior (lightfastness) of plastics, metals, complex components, coatings, paints and other materials under different irradiance levels, radiation compositions and weather conditions, at different locations.

Our sun is not only the most important source of energy for us humans but also a decisive factor in the quality assessment of components and products in terms of lightfastness. Almost all products are exposed to the sun's rays during their lifetime and have to withstand them. Artificial light in department stores, for example, also has an effect on a product and can change its appearance over time.

Request offer
light fastness testing on a test sample
Solar Simulation Test  Standards

  • ASTM C1442
  • ASTM D2565 Cycle 1
  • ASTM D3424 Method 4
  • ASTM D4329
  • ASTM D4587
  • ASTM D4798 Cycle A-1 and B
  • ASTM D4799
  • ASTM D5071 Cycle 1 and 2
  • ASTM D5208
  • ASTM D6662
  • ASTM G151
  • ASTM G154
  • ASTM G155 Cycle 1
  • DIN 75220
  • DIN EN 927-6
  • DIN EN 1297
  • DIN EN 12224
  • DIN EN 13523-10
  • DIN EN 60068-2-2
  • DIN EN 60068-2-5
  • DIN EN ISO 105-B06
  • DIN EN ISO 4892-1
  • DIN EN ISO 4892-3
  • DIN EN ISO 11997-2
  • DIN EN ISO 16474-1
  • DIN EN ISO 16474-3
  • DIN ISO 9022-9
  • GB/T 16422.2 Cycle 10 and 12
  • GB/T 2424.14 Cycle A, B and C
  • GB/T 8013.1 Xenon Test
  • IEC 60068-2-5 Procedure A
  • ISO 16474-2 Cycle B4
  • JDQ 53.3
  • MIL-STD-810G 505.5 Procedure I und II
  • MIL-STD-810G 505.6
  • MIL-STD-810H 505.7
  • prEN 1062-4
  • RTCA/DO-160G Section 16&rarr Case Study
  • SAE J2020
  • TSM0501G
  • TSM0502G
  • YY/T 0631 Xenon Test
We also offer the following tests, among others:
sand
according to the following standards, among others:

  • DIN EN DIN EN 60068-2-68
  • MIL-STD-810G
  • RTCA DO-160/li>
  • DIN SPEC 79009
  • MIL-STD-202D
  • DEF STAN 00-35

click for more infos
Blowing Sand / Dust
chemical
according to the following standards, among others:

  • RTCA DO-160G
  • DIN ISO 16750-5
  • MIL-STD-810G
  • VW 50180
  • Airbus ABD0100.1.6
  • BMW GS 95003-5

click for more infos
Chemical Resistance
pressure chamber, vacuum chamber
according to the following standards, among others:

  • JESD22-A102-C
  • MIL-STD-810
  • DIN EN 62133-2 (VDE 0510-82)
  • RTCA DO160
  • AECTP 300
  • EN 60068-2-40

click for more infos
Vacuum Tests
Explanation of the solar simulation

An important area for solar simulation is the automotive industry. Cars and trucks are sometimes exposed to intense sunlight over their entire service life. The effects are sometimes serious and affect both exterior and interior vehicle components. Paint bleaches out, dashboards discolor and can crack.

Two different influencing factors come into play here:

  • UV portion of the light
  • Thermal part of the light
While UV light ages plastics even at low temperatures, thermal exposure accelerates the aging process due to the influence of temperature. UV light in combination with water leads once again to accelerated aging, which is why this is also referred to as weathering testing.

The generation of the light is made with different emitters:

  • Xenon spotlight, which have a spectrum very similar to sunlight, but with a high infrared component
  • Metal halide emitter, which have a similar spectrum to xenon arc lamps but without the high infrared component
  • UV tubes, which are used as UVA, UVB, or UVC lamps and only allow the UV portion of the light to act on the test specimen.

Sun simulation, weathering, UV tests

These tests are intended to investigate the effects of weather-related factors such as sunlight, temperature, humidity/water, etc. on materials and surfaces. A fundamental distinction must be made between natural weathering (outdoor weathering) and artificial weathering (laboratory weathering). Both are carried out by TechnoLab.

For outdoor weathering, the objects to be tested are exposed to local environmental conditions at specific locations with special climatic peculiarities under measurement observation. This procedure requires a considerable amount of time, especially since meteorological imponderables can influence the course of the test.

In contrast, advanced laboratory weathering solutions have clear advantages. The influencing factors (irradiance, temperature, humidity, etc.) can be kept constant over the entire observation period. Thus, results can be obtained in a relatively short time, allowing reliable statements to be made about "weather fastness", "weathering stability" and "light fastness".

Light fastness / UV resistance

The influence of ultraviolet radiation (UV radiation), especially short-wave radiation, on certain materials can hardly be overestimated; their optical and mechanical properties can change significantly. Organic materials and plastics in particular undergo sometimes significant aging processes (yellowing, discoloration, embrittlement, decay) under UV light in the sun's rays. Deterioration of natural and synthetic elastomers and polymers due to photochemical reactions.

The infrared portion of the radiation can also have significant consequences such as: Jamming or detachment of moving parts, weakening of solder joints, loss of calibration, premature actuation of electrical contacts, fading of colors of color-coded components, changes in the properties of elastomers and polymers, blistering and peeling of paints and other surfaces, softening of potting compounds, and many others.

Components made of plastics such as acrylic glass, PVC, polyethylene and EPDM are tested in the laboratories, with both mechanical (hardness, elasticity and strength) and optical properties (turbidity, discoloration, gloss) being examined. The UV simulation facilities cover a wide range of radiation intensity combined with different climatic stresses.

Among other things, the following is used to perform these tests:

Xenon arc weathering

The radiation characteristics of xenon arc lamps are adjusted by using suitable filters. According to DIN EN ISO 4892-2, a distinction is made between procedure A for testing with filters for global radiation (artificial weathering) and procedure B for testing with filters for global radiation behind window glass.

UV weathering

For the realization of artificial weathering or irradiation carried out with UV fluorescent lamps, different lamps are used according to DIN EN ISO 4892-3, which have different radiation characteristics. Procedure A describes weathering with UVA-340 lamps (type 1A) and procedure B describes global radiation behind window glass with UVA-351 lamps (type 1B). With both lamps, a very good match with the radiation characteristics of sunlight is achieved. The UVB-313 lamps, on the other hand, also emit in the mid and far UV range and thus below the solar cut-off wavelength of 295 nm. These lamps are used in particular for aviation and aerospace investigations.

Case Study

Sand and Dust Testing of Encapsulated Control Electronics
According to RTCA/DO-160G Section 12

click here for more info…

Thermal Durability of Avionics Electronics
According to RTCA/DO-160G Section 16

The Challenge

Aircraft equipment installed in exposed locations may be subjected to intense solar radiation during ground operation and flight. Sunlight can significantly increase the surface temperature of electronic housings and components.
This is particularly relevant for equipment installed:
  • near aircraft windows or cockpit areas
  • in external compartments
  • inside avionics bays exposed to solar heating through aircraft structure
  • on aircraft surfaces or external installations
Solar radiation may cause:
  • excessive heating of electronic components
  • degradation of coatings and polymers
  • thermal expansion of mechanical structures
  • reduced performance or premature failure of electronics
To ensure reliable operation under these conditions, airborne equipment must be evaluated under simulated solar radiation conditions. Environmental qualification according to RTCA/DO-160G includes specific procedures to assess the effects of solar heating on aircraft equipment.
This case study presents the solar radiation qualification testing of a sealed avionics control module designed for installation in passenger aircraft systems.

Device Under Test (DUT)

The tested device was an avionics control unit responsible for auxiliary aircraft system control.
The electronics are integrated into a sealed aluminum enclosure designed for mechanical protection and passive heat dissipation.
Key characteristics of the DUT
Parameter
Description
Product Type
Avionics control electronics
Application
Passenger aircraft systems
Housing
Aluminum enclosure
Cooling concept
Passive thermal dissipation via housing
Surface protection
Anodized aluminum finish
Connectors
Aviation-grade circular connectors
Internal electronics
Multi-layer PCB assembly
Although avionics bays provide partial shielding from direct sunlight, the manufacturer required solar radiation qualification testing to verify the device’s thermal robustness.

Test Objective

The solar radiation test evaluates the ability of airborne equipment to withstand heating caused by solar exposure.
The test verifies that:
  • the enclosure withstands elevated surface temperatures
  • internal electronics remain within operational temperature limits
  • coatings and external materials resist degradation
  • the device maintains stable electrical performance
The DUT was monitored during and after the exposure to confirm continuous functionality.

Test Setup

Testing was conducted in a solar radiation simulation chamber equipped with calibrated light sources that reproduce the spectral characteristics and intensity of natural sunlight.
The DUT was mounted inside the chamber in a representative installation orientation. High-intensity lamps simulated solar radiation to heat the external surfaces of the device.
Temperature sensors monitored both surface and internal temperatures during the test.

Test Conditions

Testing was conducted according to RTCA/DO-160G Section 16 – Solar Radiation.
Typical environmental parameters include:
Parameter
Typical Condition
Radiation source
solar spectrum lamps
Radiation intensity
defined solar heat load
Exposure duration
multi-hour radiation cycles
Surface heating
monitored via temperature sensors
DUT operation
functional monitoring during exposure
The procedure simulates solar heating that may occur when aircraft are parked on airport aprons under direct sunlight.

Test Procedure

The environmental qualification test followed the procedures defined in the standard.
  1. Pre-Test Inspection
    Prior to solar exposure, the DUT underwent:
    • visual inspection
    • functional verification
    • documentation of baseline conditions
  2. Solar Radiation Exposure
    The DUT was placed inside the solar radiation chamber and exposed to simulated sunlight generated by calibrated lamp systems.
    The exposure produced controlled heating of the device surfaces.
  3. Thermal Monitoring
    Temperature sensors continuously monitored:
    • surface temperature of the enclosure
    • internal temperature conditions
    • electrical performance of the DUT
  4. Post-Test Evaluation
    After completion of the radiation cycles, the DUT was removed from the chamber for inspection and functional verification.

Post-Test Inspection

Following the solar radiation exposure, the DUT underwent detailed inspection.
Inspection activities included:
  • assessment of surface coatings
  • inspection of enclosure integrity
  • verification of connectors and seals
  • electrical functional testing

Results

The avionics control unit successfully completed the solar radiation qualification test.
Key observations:
Evaluation
Result
Surface coating degradation
None observed
Housing deformation
None detected
Internal overheating
None observed
Electrical functionality
Fully operational
The aluminum enclosure effectively dissipated the heat generated by solar radiation exposure.

Conclusion

The tested avionics control module successfully passed the solar radiation qualification according to RTCA/DO-160G Section 16.
The test confirmed that:
  • the housing withstands solar heat loads
  • coatings and materials remain stable
  • internal electronics maintain reliable performance under elevated temperatures
These results demonstrate the device’s suitability for aircraft environments where equipment may be exposed to prolonged sunlight and solar heating.

Why Solar Radiation Testing Matters

Solar radiation testing ensures that airborne equipment maintains reliable performance under intense sunlight conditions.
Environmental qualification according to DO-160 helps manufacturers:
  • verify thermal robustness of electronic equipment
  • validate enclosure design for heat dissipation
  • prevent overheating during ground operation
  • support certification of airborne systems
By reproducing solar heating effects under controlled laboratory conditions, manufacturers can ensure that avionics equipment remains reliable even in high-radiation environments.