ones A | Battery connection scenario A: suitable for a vessel with a common RF ground point. In this scenario, if your product's power cable is supplied with a separate drain wire then it should be connected to the vessel's common ground point, B | Bakery connection scenario B: suitable for a vessel without & common grounding point. In this sacs, if your product's power cable is supplied with a separate drain wire then it should be connected directly to the battery's negative terminal.