True North Equity LLC, a private-equity company that opened its headquarters in Plymouth in August, has closed on its first deal, which is to join with CIVC PartnersLP of Chicago to buy a controlling interest in KS Energy Services Inc. of New Berlin, Wis.

Jeff Wigginton, the managing partner at True North who previously was a principal at Birmingham-based Strength Capital Partners LLC, said the deal was for between $50 million and $75 million, which is the same range for KS revenue.