Mechanical interlock assemblies for panelboards and related systems and methods

An interlock assembly for use with a panelboard comprising a first circuit breaker having a first handle and a second circuit breaker having a second handle, the assembly comprising:

• an interlock panel configured to be connected to the panelboard in an installed position;
• a first protrusion on the interlock panel;
• a second protrusion on the interlock panel;
• and
• a toggle bracket pivotally connected to the interlock panel at a pivot member between the first and second protrusions, the toggle bracket comprising a first and second spaced apart arms each extending away from the pivot member;
• wherein, with the interlock panel in the installed position:
• when the toggle bracket is rotated in a first direction such that the first arm is adjacent and/or abutting the first protrusion and the first handle is then moved from an off position to an on position, the toggle bracket is held in a first position with the second arm positioned to prevent the second handle from moving from an off position to an on position;
• and
• when the toggle bracket is rotated in a second direction, opposite the first direction, such that the second arm is adjacent and/or abutting the second protrusion and the second handle is then moved from the off position to the on position, the toggle bracket is held in a second position with the first arm positioned to prevent the first handle from moving from the off position to the on position.

A method comprising:

• providing a panelboard system comprising:
• a panelboard;
• a first circuit breaker in the panelboard, the first circuit breaker comprising a first handle that is movable between an on position and an off position;
• a second circuit breaker in the panelboard, the second circuit breaker comprising a second handle that is movable between an on position and an off position;
• an interlock assembly comprising:
• an interlock panel;
• a first protrusion on the interlock panel;
• a second protrusion on the interlock panel;
• and
• a toggle bracket pivotally connected to the interlock panel at a pivot member, the toggle bracket comprising a first arm extending from the pivot member toward the first circuit breaker and a second, spaced apart arm extending from the pivot member toward the second circuit breaker;
• with the first handle and the second handle each in the off position, rotating the toggle bracket in a first direction such that the first arm is adjacent and/or abutting the first protrusion;
• moving the first handle from the off position to the on position such that the first handle moves beneath the first arm of the toggle bracket;
• in response to moving the first handle from the off position to the on position, holding the toggle bracket in a first position with the second arm positioned to prevent the second handle from moving from the off position to the on position;
• with the first handle and the second handle each in the off position, rotating the toggle bracket in a second direction, opposite the first direction, such that the second arm is adjacent and/or abutting the second protrusion;
• moving the second handle from the off position to the on position such that the second handle moves beneath the second arm of the toggle bracket;
• and
• in response to moving the second handle from the off position to the on position, holding the toggle bracket in a second position with the first arm positioned to prevent the first handle from moving from the off position to the on position.