Videos - Applications Designed and Produced by Citel. Area of application CITEL has a broad and comprehensive product portfolio of surge protection devices that provide optimal protection for any application. The following selection of application examples is intended to help you identify the right products for your application in a simple and understandable way. SPD for ESS New Surge Protectors Range DAC - DDC LED lighting protection SPD ITS SPD PV industrial SPD industrial sites SPD security systems SPD radiocom SPD PV domestic SPD Solar Farms Instructional videos The following instructional videos provide a basic technical understanding of the function, effect and use of surge protection devices. Difference between SPD-Ligthning rod When SPD must be replaced How to choose primary SPD Type 1 and 2 SPDs: Installation and Rules LED lightning: Drivers Vs SPD VG Technology