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
Most substations have. multiple transformers and multiple circuits per transformer. When a fault occurs on. one circuit, the supply voltage is depressed in the substation, thereby affecting many. circuits not just the one where the fault occurs. Depending on the stiffness of the. transmission system, other substation banks and even other substations can be. affected.