SEQUENCED SEPARATELY-DERIVED TRANSFER SWITCH CAPABLE OF SWITCHING A LOAD BETWEEN A PAIR OF POWER SUPPLIES WITHOUT INTRODUCING OPEN NEUTRAL SWITCHING TRANSIENTS

摘要

An interlock arrangement operatively associated with utility and generator side switches of an electrical panel including a first main switch associated with the first power supply and a second main switch associated with the second power supply. The interlock arrangement includes a first neutral switch associated with the first power supply, and a second neutral switch associated with the second power supply. A lockout sequencer arrangement has a first lockout that restricts simultaneous switching of the first and the second neutral switch, a second lockout configured to engage the first lockout to restrict movement of the first lockout when the first main switch is a conductive position, and a third lockout configured to engage the first lockout to restrict movement of the first lockout when the second main switch is in a conductive position.