Isotonic exercises involve moving your joints and muscles rhythmically and repetitively through their ranges of motion using low resistance, while isometric exercises are static and require you to contract your muscles without joint motion.
Substations are normally outdoors and are enclosed by a wire fence. However in residential or high density areas, the substation may be indoors and housed inside a building to restrict the humming noise of the huge transformers. slide 2 of 6 View of a Substation
This substation shows elements of low-profile construction; apparatus is mounted on individual columns. A substation is a part of an electrical generation, transmission, and distribution system. Substations transform voltage from high to low, or the reverse, or perform any of several other important functions.t resembles a distribution substation although power flow is in the opposite direction, from many wind turbines up into the transmission grid. Usually for economy of construction the collector system operates around 35 kV, and the collector substation steps up voltage to a transmission voltage for the grid.