Harold Wragg worked in the Electricity Department of the local authority of Sheffield, England, as a young man, but by 1906 had been appointed chief engineer to the Penhalonga Proprietary Mines and Rezende Mine, just north of Umtali (now Mutare), Southern Rhodesia (now Zimbabwe). Later he contributed a paper on 'Water power plants, with special reference to the power plants of the Rezende Mines, Ltd, Penhalonga, Southern Rhodesia' to the Transactions of the South African Institute of Electrical Engineers (1915, Vol. 6(6), pp. 160-).
In June 1906 Wragg married Bertha Frances Walker.