The radio's power supply has 3 connections: 0V/ground, 12V (steady plus) and a connection for the ignition (ignition on = radio on). If only the connection for the steady plus is supplied with voltage, the radio will only run for a maximum of one hour. If the ignition connection is also supplied with voltage, it will run "indefinitely".

adrizi94 has already answered this, in my case the radio fitted because a Blaupunkt radio was already installed before, I only needed to extend the cable 1:1. You can order suitable wiring harnesses for most cars on the internet.