You have learned that it is preferable to use the Class 2 LED driver in the LED signage and lighting applications in order to better manage and limit the potential risk of electric shock hazard in installing and operating the devices. However, many people confuse the class 2 (Numeric “2”) with the class II (Roman Numeral “II”) power supply. They are both valid standards, controlled by different organizations, but they are meant to provide different protections in different methods. Here is a brief explanation of each designation to help you distinguishing between the two.
Class 2: Class 2 power supplies are governed by UL (Underwriters Laboratories) 1310 standard. The main focus of UL-1310 is to ensure the output from each channel of the power supply cannot exceed 100 Watts (or five times output voltage if is it is lower than 20V) in any given circumstances, such as the rated working temperature, start-up or shut down process and the faulty conditions. UL-1310 is applied to oversee the Class 2 LED driver as well. If you are a US domestic LED sign or lighting application builder, you need a Class 2 LED driver, not a Class II power supply.
Class II: Class I and Class II are both specified in the EN-60950 (the European standard). The former requires a ground connection – usually done by using the 3-prong AC input, established, so the extra current generated in the fault condition can be quickly shunt to ground without damaging the property or the operator. The latter calls for a double insulation on the primary and the secondary side of the power supply if the ground connection is missing. Class II power supplies are typically used in the telecommunication industry. You can find it resides in many consumer electronics products, such as the Digital Video Recorder, network switch and wireless router.
If your signage or lighting application is made up of LED related illumination technology, be sure to employ a Class 2 LED driver to power your system. A Class 2 LED driver can consist of several output channels but the maximum output power of each channel won’t exceed 100 watts. By limiting the absolute maximum output power to the UL predefined level – 100 watts, the Class 2 LED driver can reduce the chance of producing excessive out-going current, over-heating the cables and creating an electric shock hazard. Thus, it can support a safer installation and operation experience for your applications.