Dual contactor electrical panelboard assembly, systems and methods

A panelboard assembly for use in environments in which combustible or ignitable materials are present comprising:

• a first subpanel assembly comprising:
• a first contactor assembly configured to be electrically connected to a three-phase power supply;
• and
• a first branch breaker assembly electrically connected to a load side of the first contactor assembly and configured to be electrically connected to a first group of loads, the first branch breaker assembly including a plurality of first branch circuit breakers, and each of the plurality of first branch circuit breakers is configured to switch on or off an electrical connection to a respective one or more loads in the first group of loads,
• wherein the first contactor assembly is configured to connect or disconnect power to the first branch breaker assembly and to the first group of loads all at once;
• a second subpanel assembly electrically connected in parallel to the first subpanel assembly, the second subpanel assembly comprising:
• a second contactor assembly configured to be electrically connected to the three-phase power supply;
• and
• a second branch breaker assembly electrically connected to a load side of the second contactor assembly and configured to be electrically connected to a second group of loads, the second branch breaker assembly including a plurality of second branch circuit breakers, and each of the plurality of second branch circuit breakers is configured to switch on or off an electrical connection to a respective one or more loads in the second group of loads,
• wherein the second contactor assembly is configured to connect or disconnect power to the second branch breaker assembly and to the second group of loads all at once;
• an enclosure enclosing the first subpanel assembly and the second subpanel assembly;
• and a first power distribution block (PDB), a second PDB, and a third PDB each electrically connected to a main breaker assembly, the first contactor assembly, and the second contactor assembly, wherein each of the first PDB, the second PDB, and the third PDB is disposed downstream of the main breaker assembly and upstream of both the first contactor assembly and the second contactor assembly, wherein each of the first PDB, the second PDB, and the third PDB is associated with a phase of the three-phase power supply, wherein each of the first PDB, the second PDB, and the third PDB is configured to receive single phase electrical power through a single bus and distribute the received single phase electrical power to the first contactor assembly and the second contactor assembly via separate buses.

A method of assembling an electrical assembly for use in environments in which combustible or ignitable materials are present, the method comprising:

• providing a panelboard assembly, the panelboard assembly including:
• a main breaker assembly configured to be electrically connected to a three-phase power supply;
• a first subpanel assembly including:
• a first contactor assembly electrically connected to the main breaker assembly;
• and a first branch breaker assembly electrically connected to a load side of the first contactor assembly and configured to be electrically connected to a first group of loads, the first branch breaker assembly including a plurality of first branch circuit breakers, and each of the plurality of first branch circuit breakers is configured to switch on or off an electrical connection to a respective one or more loads in the first group of loads,
• wherein the first contactor assembly is configured to connect or disconnect power to the first branch breaker assembly and to the first group of loads all at once;
• a second subpanel assembly electrically connected in parallel to the first subpanel assembly and including:
• a second contactor assembly electrically connected to the main breaker assembly;
• and
• a second branch breaker assembly electrically connected to a load side of the second contactor assembly and configured to be electrically connected to a second group of loads, the second branch breaker assembly including a plurality of second branch circuit breakers, and each of the plurality of second branch circuit breakers is configured to switch on or off an electrical connection to a respective one or more loads in the second group of loads,
• wherein the second contactor assembly is configured to connect or disconnect power to the second branch breaker assembly and to the second group of loads all at once;
• and
• a first power distribution block (PDB), a second PDB, and a third PDB each electrically connected to the main breaker assembly, the first contactor assembly, and the second contactor assembly, wherein each of the first PDB, the second PDB, and the third PDB is disposed downstream of the main breaker assembly and upstream of both the first contactor assembly and the second contactor assembly, wherein each of the first PDB, the second PDB, and the third PDB is associated with a phase of the three-phase power supply, wherein each of the first PDB, the second PDB, and the third PDB is configured to receive single phase electrical power through a single bus and distribute the received single phase electrical power to the first contactor assembly and the second contactor assembly via separate buses;
• electrically connecting the panelboard assembly to the three-phase power supply by electrically connecting the main breaker assembly to the three-phase power supply;
• electrically connecting the first group of loads to the first branch breaker assembly by electrically connecting one of the plurality of first branch circuit breakers of the first branch breaker assembly with the one or more loads in the first group of loads;
• and
• electrically connecting the second group of loads to the second branch breaker assembly by electrically connecting one of the plurality of second branch circuit breakers of the second branch breaker assembly with the one or more loads in the second group of loads.