Skip to content

Q-SUN Xenon Arc Rotating Rack Weathering Tester XE-2

The Q-Sun Xe-2 xenon tester offers a large-capacity rotating rack and its single air-cooled lamp is more economical than water-cooled lamps. 

In a few days or weeks, the Q-Sun tester can reproduce the damage that occurs over months or years outdoors. The versatile Q-Sun Xe-2 tester is the simplest, most reliable, and easiest-to-use rotating rack xenon arc tester available.


The Q-Sun Xe-2 tester is an exceptional rotating rack xenon arc chamber that is highly versatile, reliable, and user-friendly. It supersedes the Q-Sun B02 model and offers a full range of weathering, lightfastness, and photostability features at a breakthrough price. The Xe-2 features a central light source positioned vertically, with a filter system surrounding it. The test specimens are mounted facing the light on a drum that rotates around the central lamp like a carousel. 

The tester precisely manages essential test parameters, such as spectrum, irradiance, relative humidity, chamber temperature, and black panel/black standard temperature, with the option to include front or back water spray. The Xe-2's xenon arc lamp best reproduces full-spectrum sunlight and can match almost any global xenon test standard with the help of various optical filters.

  • Daylight Filters are used to simulate direct, noon summer sunlight.  They provide the best correlation to natural exposures for most applications.  Materials that are typically used outdoors (e.g. roofing and exterior coatings) should be tested using daylight filters.
  • Window Glass Filters produce spectra equivalent to sunlight coming through window glass.  This spectrum can also simulate other indoor lighting, such as the harsh lighting found in a typical commercial or office environment.  Window glass filters are used for indoor materials such as printing materials and textiles. 
  • Extended UV Filters allow excess UV below the normal cut-on of natural sunlight.  They are used to produce faster or more severe test results.  Extended UV Filters are specified in some automotive test methods and are sometimes used for aerospace applications. 

The Q-Sun Xe-2 tester can accelerate test results by subjecting specimens to the equivalent of noon summer sunlight for 24 hours a day, every day. This means that specimen degradation can be highly accelerated, and outdoor damage that would take months or years to occur can be reproduced in just a few days or weeks. The tester's full-spectrum xenon lamps are air-cooled, making them more cost-effective, efficient, and low maintenance than water-cooled lamps. The optical filter lanterns produce the spectra specified in many global weathering and lightfastness test standards and consist of an outer borosilicate or quartz glass cylinder and two sets of 7 inner filters arranged in a two-tier heptagon.

The SOLAR EYE Irradiance Control System constantly monitors and manages lamp output to ensure precise light exposure and maximise test result repeatability and reproducibility. Irradiance control is available at 340nm or 300-400nm TUV (Total UV). Relative humidity (RH) control is standard in the Q-SUN Xe-2 tester.  It allows the user to simultaneously control and display RH, black panel temperature, and chamber air temperature.  Note that purified water is required to properly operate the RH system in the Xe-2 tester.


Q-SUN Xe-2-H: full-spectrum sunlight, rotating rack specimen holder, with humidity control
Q-SUN Xe-2-HS: full-spectrum sunlight, rotating rack specimen holder, with humidity control and water spray
Q-SUN Xe-2-HBS: full-spectrum sunlight, rotating rack specimen holder, with humidity control and water spray (front and back)

Technical Data

  • Brand
  • Capacity
    31 Specimens (51 x 102 mm)
  • Temperature Range
    +50°C to +100°C (Light Cycle)
  • Electrical
  • Castors
  • Humidity Range
    20% to 95%


At Thermoline, we strive to supply helpful customer support to ensure that you get the most out of our products. We are committed to providing whatever support our customers need, wherever they are in the world. If you can't find your solution in the below FAQs or Knowledge Base, please contact our friendly support team.

What is the difference between UV and Xenon testing?

UV and Xenon testing are accelerated weathering tests commonly used to evaluate the durability and performance of materials, coatings, and products under exposure to sunlight and other environmental factors. However, there are some critical differences between these two types of testing.

UV testing typically uses specialised lamps that emit UV radiation at specific wavelengths, typically in the range of 280 to 400 nanometers. The lamps are arranged in a chamber designed to simulate the effects of sunlight, and the test specimens are exposed to the UV portion for a set period. UV testing is often used to evaluate the resistance of materials and is ideal for testing residual strength and polymer degradation in the form of gloss loss, strength loss, yellowing, cracking, crazing, embrittlement.

Xenon testing, on the other hand, uses a different type of lamp that emits light across the entire visible spectrum and some UV and infrared radiation. The lamps are typically arranged in a chamber designed to simulate both sunlight and humidity, and the test specimens are exposed to the light and humidity for a set period of time. Xenon testing is often used to evaluate the resistance of materials to colour fading, chalking, cracking, or other forms of degradation that can be caused by exposure to sunlight, heat, and moisture.

Why do you need lab grade pure water for the water spray in a Q-Sun?

Impurities in water can leave deposits on test specimens, thus spoiling the opportunity to evaluate their appearance as degradation occurs. Also, the tester can suffer performance issues or mechanical breakdowns due to the prolonged deposition of impurities from water.

Q-Lab offers a water repurification system to significantly reduce the cost of running the Q-Sun tester’s optional water spray system. The system can save over 1,000 litres of expensive, purified water per day in a test cycle that calls for several hours of water spray and can pay for itself in a matter of months. 

How many hours in Q-Sun equals x-amount of years outdoors?

Weathering experts have tried to find that magic number for decades, but there is no such one. No matter how the question is formulated, the answer is always the same: “It depends!” It depends on one simple reason: Mother Nature is not as reliable as lab equipment!

There is no direct conversion between the hours of exposure in a Q-Sun tester and the amount of time spent outdoors, as the intensity of UV radiation and other environmental factors can vary widely depending on location, season, and weather conditions. So, unfortunately, there is no magic number that we can you that can tell you.

Q-Sun testers are designed to simulate accelerated aging under controlled conditions, and the results are intended to be used as a comparative tool to evaluate the relative performance of different materials or coatings. Outdoor exposure, on the other hand, is subject to a wide range of variables that are difficult to control or predict.

What irradiance control point should I choose?

Weathering and lightfastness test standards typically specify an irradiance level as both a magnitude and the wavelength (or wavelength range) where it is controlled. Irradiance in fluorescent UV and xenon arc weathering testers can be controlled using narrowband or wideband setpoints.

The selection of a narrowband control point in a QUV fluorescent UV tester is determined by the UV lamp type in use. We suggest controlling a Q-Sun xenon arc weathering tester using a wavelength or wavelength region in which the test specimen is sensitive. If the user is primarily concerned with colour change, then a 420 nm control point is often used. If the primary area of concern is another type of physical property change, gloss loss, for example, then a 340 nm control point is frequently used. A wideband TUV control point (300-400 nm) can be viewed as a compromise between the two narrowband (340 nm & 420 nm) control points, as it uses the total irradiance over the range 300 400 nm as its setpoint.

The selection of optical filters in a xenon arc tester also usually parallels this selection of irradiance control point. Typically, users testing with daylight optical filters use a 340 nm control point, while users of window glass optical filters generally use 420 nm control point. 

Does Q-Lab’s fluorescent UV and xenon lamps meet International Standards for irradiance?

International standards for operating weathering test apparatuses using Fluorescent UV and Xenon Arc lamps often include requirements for relative spectral power distributions (SPDs) of the light sources. These SPDs define ranges for what percentages of a given light source’s irradiance fall within a specified bandpass, e.g. 290-320 nm or 360-400 nm.

Both ASTM and ISO standards provide important sets of SPD reference tables. Fluorescent UV spectral tables are provided in ASTM G154 and ISO 4892-3, while xenon arc requirements are found in ASTM G155 and ISO 4892-2. These tables are defined for three different general classifications of lamps and filters: Daylight (outdoor sunlight), Window (behind glass), and Extended UV (UVB-313).

Q-Lab’s UVA-340, UVA-351, and UVB-313EL lamps all meet the specifications of both ASTM G154 and ISO 4892-3 for Daylight, Window, and Extended UV.

The following Q-Lab UV filters used in Q-SUN weathering testers meet the spectral requirements specified in ASTM G155 and ISO 4892-2. The latter standard does not include a specification for Extended-UV.

Table 1 (Daylight filters):                   Daylight-B/B, Daylight-Q, Daylight-F

Table 2 (Window glass filters):        Window-B/SL, Window-Q, Window-IR

Table 3 (Extended-UV filters):         Extended UV-Q/B

The only Q-Lab standard optical filters that fall outside of these SPD requirements are the Extended UV-Quartz and the Window-SF5 filters. The Extended UV-Quartz filter is required only in a few specialty aerospace standards, while the Window-SF5 filter is used only in automotive standards specifying glass with higher cut-on wavelengths than architectural glass.

Can the Q-Sun run “Solar Radiation” tests found in environmental testing standards?
“Solar radiation” standards describe tests that are designed to characterise the performance of electronics subject to outdoor use or other harsh environments. The two most important solar radiation standards are MIL-STD-810G and IEC 60068 2 5. The Q-Sun product line can be used to meet these environmental “solar radiation” tests. A critical fact to note is that these standards are not specific test methods, despite having sections called “test methods.” Both standards spend considerable space discussing the concept of “tailoring”, which gives laboratories and engineers flexibility in designing tests that apply the environmental stresses discussed in each section. Thus not only are these standards performance-based in allowing multiple hardware designs, it is also possible to alter the actual test conditions if the result meets the general intent of the section. MIL-STD-810H clearly states:

“It is important to note that this document does not impose design or test specifications. Rather, it describes the environmental tailoring process that results in realistic materiel designs and test methods based on materiel system performance requirements.”

MIL-STD-810H and IEC 60068-2-5 both include numerous statements reinforcing this flexibility in selecting test conditions. In fact, the “solar radiation” tests in these standards are impossible to run in any chamber because they show a target spectral power distribution from 280 to 3000 nm, which no artificial light source can meet. Because no single light source actually meets the specification, the user of the standard must apply sound and reasonable engineering principles to tailor the test by defining how the relevant environmental stresses will be applied. Q-Lab has prepared two special letters confirming that Q-Sun xenon-arc weathering testers can meet the performance requirements of Method 505.7 of standard MIL-STD-810H, provided that the document’s guidance on “test tailoring” is followed. Laboratories who need to add these standards to their scope of accreditation need to write a procedure that addresses specifically what test tailoring they have selected for their Q-Sun.
What’s the difference between Narrowband and Wideband irradiance control?

In Xenon and UV fluorescent accelerated weathering testing, an irradiance setpoint value is an incomplete information without reference to the wavelength or wavelength range it represents. There are two classes of irradiance setpoints.

Narrowband irradiance setpoints include 340 nm and 420 nm, representing a 1 nm wide bandpass centred on the single wavelength value indicated (i.e. ½ nm on either side of 340 nm, for example). Narrowband irradiances use units of “Watts per square meter per nanometer.” This can be written as either W/(m2∙nm), W/m2/nm, or W∙m-2∙nm-1.

Wideband irradiance setpoints (usually “TUV” or “total UV”) are an integration of the irradiance from all wavelengths between two endpoints, usually 300-400 nm (accelerated laboratory) or 295-385 nm (outdoor). As a result, wideband irradiance values are generally much larger than narrowband irradiance values. Wideband irradiance is measured in “Watts per square meter,” written as W/m2 or W∙m-2.