Triplett entered the Navy from the state of New York and, during the Spanish–American War, served as an Ordinary Seaman on the USS Marblehead.

He was awarded the Medal of Honor five months later, on December 14, 1898, for his actions during the operation.

Triplett reached the rank of Chief Boatswain's Mate before leaving the Navy.

Marblehead at the approaches to Caimanera, Guantanamo Bay, Cuba, 26 and 27 July 1898.

Displaying heroism, Triplett took part in the perilous work of sweeping for and disabling 27 contact mines during this period.