An electrical contactor assembly is provided including: an electrical contactor; an electrical bus bar; a panel; at least one post protruding through the panel and in contact with the electrical bus bar, the post being constructed from an electrically and thermally conductive material, wherein a first end of the at least one post is configured to electrically and thermally connect to the electrical contactor; and a liquid cooled heat sink thermally connected to a second end of the at least one post through the electrical bus bar, wherein the liquid cooled heat sink in operation circulates liquid coolant through the liquid cooled heat sink to absorb heat.