31. He founded Four-Phase Systems to commercialize the technology, and sold the company to Motorola in 1981. 32. Household wiring does not usually use three-phase supplies and the clash only occurs in three-phase systems . 33. Aqueous two-phase systems can also be generated by introducing a high concentration of salt to a polymer solution. 34. In North America and countries that use their system, the 120 / 240 V split phase system is used. 35. In single phase systems without N, both incoming conductors must be disconnected if the incoming feed is shut off. 36. Calculations in unbalanced three-phase systems were simplified by the symmetrical components methods discussed by Charles Legeyt Fortescue in 1918. 37. Two-phase systems can also be implemented using three wires ( two " hot " plus a common neutral ). 38. His main work was in the field of thermodynamics, in which he studied the equilibrium of multiple-phase systems . 39. Still, a boost-phase system may do more to enhance American security than the Pentagon's seriously troubled program. 40. Three-phase systems can be connected to give various combinations of voltage, suitable for use by different classes of equipment.
