Power Relays: FTR-LY Series FCL Components FTR-LY Series are slim-type, 1-pole, medium load control power relays featuring high-insulation in a small package. Features include a minimum insulation distance of 8mm, 4,000VAC dielectric strength, and 6,000V surge strength. The FTR-LY Series also have UL94 flame class V-0 plastic materials and are UL, CDA, and VDE approved.