Afternoon guys. Recently been asked to do a generator changeover switch for a friend it’s a 6.0kva standby generator . The earthing system is tnc-s . Just seeking a bit of advice with regards to earthing requirements as it’s a portable gen . Also it will be sitting on top of block paving . Can’t see an easy way to drive an eart rod in. The output wiring is neutral and earth are separate . I’m a fully qualified electrician have all up to date qualifications just haven’t had any dealings with standby generator equipment . Any advice would be appreciated.