Three seconds in the real world equals one minute in Norrath, so an hour in Norrath passes in three minutes and a Norrathian day passes every 72 minutes.
Norrath
Earth
1 minute
3 seconds
1 hour
3 minutes
1 day
72 minutes
From time to time, the Norrathian clock will freeze. This is a client-side issue. Time still moves on the server but the client does not know it. Zoning will correct this.