You Do Need power plug adapter while traveling from Armenia to South Africa.

Here is Why You Need An Adapter

The outlet and plug type used in South Africa are C, M and N and in Armenia are C and F. This is how they look like.

Armenia

In Armenia, outlets of type C and F are in use.

Type C

Type F

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N