To reduce voltage drop of 12v to the main cabin I an installing a 10mm² ring-main, that is cable going in both directions around a room, from the fuse box, giving a sum of 20mm² conductor for both negative and positive lines.

1. I've bought the cable and 24 off 10mm x 6mm crimp terminals from
   Torberry Connectors at cost of £102.55 inc P&P
   The pink and grey surrounding the copper are the actual covering. The darker red and black is the transparent overlay, which you can see by the join.
   

   

   
   I bought a Weller 40w soldering iron and although it can heat the crimps enough to melt solder it cools to quickly for the 10mm cable to settle in so i had to crimp too :(
   

   

2. As I am going to run spurs from the ring-main I am using stand-alone post terminals to which I can fix multiple wires each. I have bought 6 red and 6 black from 12voltplanet.co.uk, hence the 36 lugs mentioned above. I will make boxes to house the terminals as I progress. Cost £57.47 inc P&P
   

   

3. I am also replacing the main cables from the MPPT to the batteries and from the batteries to the fuse box with 16mm² cable and for which I will use 16|8 crimps for the battery connections (4 off) and 1 off 16|6 for the fuse box
4. To mange the heavy cable I have bought a wire cutter (£33.23) and cable stripper (£20.50) from Farnell
   

   

   
   Both arrived around midday 11th Nov but the Nipex stripper is all but useless.
5. Have ordered 16|8 and 16|5 crimp terminals and 2 each of 15A and 30A fuses from 12voltplanet, pity I didn't get it together for one order (P&P etc.)
6. Ordered 4m of red and 3m of black16mm² from Batteries and Solar, Plymouth