V
vaughant
General drawing looks ok,can't say I've seen many 4 pole DB's in my 17 years of industrial work,nearly always 3 phase but with the neutral and earth into a block internally so I wouldn't be too concerned overall if that's all that's available.Fitting 4 core swa is always a good move IMO as it keeps the earth arrangements neater and safer.How crap is that db1 in the existing photo?just two meter tails stuffed in from conduit!!!!If you need an example of how you generally view power distribution in schematics I'll try and post it up on here,although I like your overview and would certainly add that as well,for sparks like me who generally deal in schematics it's nice to have the more traditional line drawings as well.