Always consult the rules for the court in which you are practicing. This includes checking both the applicable state-wide rules and the local court rules.
State-wide rules (such as the Rules of Criminal Procedure and Juvenile Rules) are found in the Pennsylvania Code; browse to the 2xx titles to find them.
Pennsylvania is divided into 60 Judicial Districts, most of which have the same boundaries as the Pennsylvania counties. (Some Judicial Districts combine two counties.) For cases at the Court of Common Pleas level or below, check the Judicial District's local rules, which usually are posted on the court or county website.