[1] In 1919 Wandel completed his apprenticeship as an electrical engineer and later worked as a technician.

[2] In 1931 he was sent to the Soviet Union and graduated from the International Lenin School, joined the All-Union Communist Party (b) and worked at the Marx–Engels–Lenin Institute.

[3] After the end of World War II, Wandel returned to Germany and served as the chairman of the Central Administration for People's Education from 1945 to 1949 and then Minister of People's Education from 1949 to 1952.

After his term as minister ended he was the secretary of Culture and Education Department at the Central Committee of the Socialist Unity Party.

From 1958 to 1961 he served as DDR's ambassador to the People's Republic of China and then was appointed deputy Foreign Minister.