I normally charge my Motorola mobile in my own car. The charging lead for this obviously has a means to cut down the 12v car current to the 4.8v required for the mobile battery. To charge my phone when I am in a commercial lorry which has 24volt equipment do I need to get a different charging lead to cut down the 24v. It`s not always the same lorry but is usually 24v. I don`t drive them, just a passenger.