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	Subject - Tough one! Skybox I have a garage (woodshop) 270 foot from my house. I need 100 amp service. I have purchased 4/0,4/0,2/0 URD wire. My intent was to hook the 4,4,2 to a 100 amp breaker (Square D)from the main in the house and then connect the other end to a 100 amp sub panel in the garage. My problem is the 4,4,2 is to large to fit into the 100 amp breaker on the main. Are there breakers avaiable to handle this size wire? If not, sure would appreciate some alternatives. v/r Roger iwire No 100 amp breaker that will fit in a home panel will have lugs to fit 4/0, splice on an appropriate size wire (1 AWG AL IMO) to fit the breaker with the correct connector. You can make this splice in the panels or in a separate box outside the panels. Skybox Iwire, Thanks for the reply and great suggestion. If you don't mind I have a few follow on questions based on your recommendation. The splice I assume is made via a special lug designed for the Square D main panel that allows the 4,4,2 wires to be connected to smaller wires that would fit the circuit breaker? I also assume a neutral lug commensurate with the size of the 4,4,2 would also need to installed? You also stated the splice could be made in a box outside the panels. What type of box? v/r Roger LIVEWIRE Excellent question. Great answer. You'd be surprised how often we get a call from the field asking this question. Problem is, some of the guys think they got a barber's liscense too. David Hyatt Sky box, I disagree with the above post for the following reason. I assume the larger wire size is for voltage drop. In keeping with that voltage drop idea, I wouldn't splice a smaller cable to it. Though I have never seen these, but when studying VD I asked the same question, They make crimp adaptors to do exactly what you are needing. Check with your local supply house they should know. iwire When you do the voltage drop calculations you will find a few feet of regular size cable on a 270' run makes little difference. First the voltage drop on this feeder if it run entirely with 4/0 AL 240 Volt circuit 100 amps of load 270' of 4/0 AL conductor will only be 5.4 volts (2.25%) Now the voltage drop if we have 10' of 1 AWG AL on each end. 10' 1 AWG + 250' 4/0 + 10' 1 AWG = 270' This would end up with 5 volts of drop on the 4/0 and 1 volt of drop on the 20' of 1 AWG for a total of 6 volts of drop instead of 5.4 volts of drop. Not worth thinking about and my figures are based on a full 100 amp load and splicing in 20' of the smaller cable. Yes they make devices called pin adapters to crimp on the end of 4/0s that reduce the size, two issues with these. 1)You need the correct hydraulic crimping tool to install them. 2)Straight ones will never fit in the gutter space of a 14.5" wide panel. I spend a lot of my time running oversize wires for voltage drop, we have run 4 AWG copper for 20 amp 120 volt receptacle circuits and you can bet we spliced down the 4 AWG to 12 AWG at the outlets. Skybox Iwire, The crimpers may be a show-stopper for me. What about split bolts or possibly some type of plug on lug kit to accomplish the samething. Roger iwire Roger unless you have a really packed panel you can probably splice inside the panel with one of these splicer reducers. Here is the Ilsco brand part I would use. Part # SPA-4/0 Wire Range 4/0-6 STR. Height 1-3/32" Width 1" Length 2-5/16" iwire By the way here are some pin adapters they do come in handy when you have the room. These first ones are offset so you can fit the big pin adapters side by side on a 3 pole breaker. Phase A & C rotated to push them away from each other with phase B rotated forward most times. Now standard ones, you can get angled ones too. These are specified by some engineers for all feeder connections and if you have the right tool these are really great. frenchelectrician skybox most common pratice that i do use the inline reducer splice kit or lugpin connector adapator but as iwire [bob] saying is check the room in the box if crowded just add 12 by 12 by 4 box next to it and go from there ps dont use 8by 8 it is too small for bending the large wires btw . merci , marc David Hyatt THANKS FOR THE PICTURE. NOW I KNOW THE PRODUCT I AM PROMOTING. TRUEFULLY I HAVE NEVER SEEN ONE. Skybox Thanks to all for the great suggestions...I'm off to the supply house :) Sincerely, Roger