Tom...thanx for the replie...with a load of 251 amps now a 200/100 amp setup as you described wouldn't leave much room for any more equipment at the shop. The owner wants 400 amps in case of future needs.Due to the location of the panels that exsist in the building,it is not feasible to install seperate disconnects.The wiring in the two exsisting panels is a mess to say the least.Guys adding and adding circuits over the years without properly figuring the load and causing a dangerous situation in my opinion.I will relocate some of the heavy loads to the new 400 amp Panelboard...like the spray booth and the air compressor which is drawing off the 100 amp sub panel.
I did consider the type of installation you mentioned.That is what we do around here for residential 400 amp services...with dual barrel lugs and two 200 amp main breaker panels.We also feed the 320 meter with dual 4/0 URD in a 4inch PVC from the POCO manhole.
thanx
shortcircuit
