The difference between FS-40 UV aging lamp and UVB-313 aging lamp

In many cases, customers of UV accelerated aging test have requirements for FS-40 lamp tubes. But in reality, using UVB-313EL lamp is a better choice. UVB-313EL is quite different from FS-40 lamp in size, so it has a significant price advantage.

As shown in Figure 1, the spectral power distribution (SPD) curves of the two UV lamps have the same shape. The only difference is that the irradiance of the UVB-313EL lamp used in the UV aging test chamber without irradiance control function is higher.

 

Application of FS-40 Ultraviolet Lamp in Standards

 

FS-40 lamps are mainly used in the test process of SAE J2020. The early version of the standard required the use of FS-40 UV lamps. The reason is that in the 1970s, before the solar eye irradiance control function was developed, FS-40 was The only light tube available at the time. However, after 2002, this requirement was abolished, and the requirement of the subsequent relevant standard is "use the UVB lamp with the 313nm nano-band peak value described in Table 3 of ASTM G154".

The irradiance setting value of SAE J2020 is determined by studying a large number of old model UV aging test chambers using FS-40 lamps. The irradiance at 310nm was specified in the update of j2020 in 1995 and 2002 The average value is 0.48w/m2. Unlike most standards, SAE J2020 allows ±15% deviation for equipment without irradiance control function, but additionally requires an irradiance test for equipment without irradiance control function every 400 hours to confirm the radiation illuminance. Under the requirements of this standard, the UVB-313EL lamp still cannot meet the requirements.

 

Many calibration committees refer to the test conditions of SAE J2020. However, with the iterative update of the SAE J2020 standard, the relevant standards have not updated the test requirements in time.

 

IEEE Std C57.12.30 is one example. Such standards often do not contain irradiance control points and do not recognize the validity of UVB-313 lamps. After participating in the formulation and updating of a large number of standards, there are still a large number of standards that have not been updated so far.