3-alkoxy, thioalkyl and amino-4-amino-6-picolinic acids having a halogen, alkyl or mono-, di- tri- and tetra-substituted aryl substituents in the 6-position, and their acid derivatives, are herbicides demonstrating a broad spectrum of weed control. The multi-component LED lamp comprises an outer case housing with at least one heat sink and an array of LEDs disposed therein. It may be employed in either real-time or off-line analytic applications for balanced or unbalanced electric power systems, in particular for monitoring and analyzing unbalanced conditions in three-phase electrical networks and for the accurate calculation of short-circuit conditions.