In cases like this, it is acceptable to solder on a short extension of lighter gauge wire to connect directly from the bus to the command station or booster.
Resistance in wire depends on two things: resistance of the wire itself based on diameter/gauge and the length of the wire. A short wire can carry a high load that a longer length of it cannot. I faced the same situation and so do most DCC users, as command stations connection rarely accept wire the size commonly used in busses.
Use the largest gauge wire that will fit the connection. Use as short a length as possible. Even two feet is getting long, so shorter is better. Make a good connection to the fat wire, preferably by soldering. Properly insulate everything.
Mike Lehman
Urbana, IL
Ordinary zip cord (lamp cord) which is usually 16 gauge stranded will work fine. 18 guage is enough for that matter. Your 12 gauge bus wire is electrical overkill. I find 12 gauge too stiff to work easily even with long nose pliers. I use 14 gauge just cause it's easier to bend. We use such heavy wire for buses 'cause it's common house wire, easy to get, and mechanically very rugged. But both 14 and 12 gauge is much heavier than we need from an electrical standpoint. So a lesser gauge jumper from your 12 gauge bus wire to the power pack is just fine.
David Starr www.newsnorthwoods.blogspot.com
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