If we use it as a preposition, conjunction and as a relative adverb to refer to time, it does not have any accent. 

As a preposition, it refers to the moment when something happens.

Example:

• Cuando/ when I was young, I played soccer with my neighbors. 

• My father always talked about cuando/ when I was a child.

As an adverb related to time.

Example:

• Cuando/when you arrive, dinner will be ready. 

With the value of si or  en caso de que: Cuando/When the moment come, you must travel.

It can have the value of despite the fact that or although: The employees drink every weekend Cuando/although the priority is to save money. 

It can be used as because or since: You really like languages /cuando/ /because/since/ you have learned 6.