Have you read the book?
Please consult the Flight Crew Training Manual....also, the FCOM, Volume two of FCOM 3. In addition, have a look at the Airbus Flight Operations Bulletin regarding the Optimum Use of Weather RADAR.
This should answer most of your questions.
FCOM 1....a systems description of the RADAR may be of help.
Of course, as always, your company's SOPs have priority over anything else.
Fly safe,
PantLoad