TT Scale. The Ideal Scale.

The blue wire is the function output common. It does not require connection when the locomotive is prepared for DCC i.e. the NEM 651 socket. For locomotives that are not DCC prepared it may be needed.

Blue wire is also supposed to provide "better" lighting on the front and rear lights, when used with the white and yellow wires. It is wired up to the 7th pin on the 8-pin connectors (NEM 652 and NMRA). But, as CSD said, with 6-pin NEM 651 interface, the locos use viltage from black or red wire instead.

ConducTTor wrote:What's "better" lighting? More functions?

No, same functions (on/off) The documentation says that using black or red wires would "make the lights dimmer", but I have not done any experimentation to either confirm or disprove that statement.

No, same functions (on/off) The documentation says that using black or red wires would "make the lights dimmer", but I have not done any experimentation to either confirm or disprove that statement.

If you use the Blue wire you get full DC for the function output. If you do not use the blue wire you pick up power from one half of the frame and only get half wave DC thus the lights are usually dimmer.

Bill Dixon