Hi, am in the process of wiring my boats electrics in, I have a twin battery system with a pirko switch, and have 2 electrical fused panels to connect my electricals to, I ran a 30 amp twin cable from the common post to these, and piggy backed them to connect them together, connecting the positive to positive, and neg(ground) to neg, now heres where I got confused,I can see where to attach my power cable from bilge pump, vhf, lights etcto the fused switch but there is no facility to do the same with the neg cable from each device, I think I may need to have a seperate bus bar??? and if so, can I piggy back the earth cable that is attached to the fused switch panel or do I have to run another one in independant of that one? any help very gratefully received.