In this section we are talking about Track Feeders for your track and turnout Frog.
Track feeders connect you power from your DCC system to the track. With metal rail joiners, in theory one would only need one 2 track feeders with one for the opposite side rails to power all the track since the current would be passed by the rail joiners to the next rail it is joining and so on down the length of track.
But reality shows us that relying on a single track feeder set eventually leads to unreliable operation soon after you get it working. Why? If one attempt to fix the problem they will soon discover it is the rail joint involving a rail joiner. Rail joiners are the most common failure point in a track system yet they are a necessary evil in the operation of our layouts. To improve the layout reliability, we first must understand what the rail joiner failures are and then understand how to fix the problem.
1) Rail joiners server two purposes:
a) Mechanical alignment of the rails between independent rail sections (track).
Without proper alignment of the rails, our trains will derail.
b) The passing of electrical current from rail to rail assuming this is a metal rail joiner.
The metal of the rail joiner applies spring pressure to the metal rail's web and base.
Each rail joiner has two electrical connections. One for each rail being joined.
The connection contact area is hidden from view behind the rail joiner.
2) Rail Joiner Failure Mechanisms
a) Mechanical failure occures post installation when the track or rail is subject to sever movement forces such that is losses spring pressure on the rail web and base. AKA lose rail joiner.
The electrical problem are not so obvious and hidden from view. The common type of metals we use to make rail with all oxidize. This is the metal chemically reacting to the oxygen in the air. Depending on the type of metal, the oxidation or "oxide metal" that results may or may not conduct. Non conducting oxide like that found in brass track prevent the rail joiner from passing current from one rail to the other and at the same time from the rail to the wheel of the locomotive. But even if the oxide conducts, that does not make it a good conductor. It is a highly resistive conduction the is far less than unoxidized or "raw" metal to raw metal can offer.
For locomotive and the top of the rails, we can address this oxidation by cleaning the wheels and track since they are exposed and easily accessible for cleaning. There are many tools to address this problem and we are well aware of problem when we get engine the run poorly on the track.
On the other hand rail joiners are part of the track infrastructure and are installed once as part of process of laying track down permanently. In terms of metal to metal contact, We will not have any access to the raw In otherwords we do NOT have easy access to the metal to get rid of the oxide.
The oxide can lead to high resistance electrical connection.
There are two types of modelers.
1) Those that like to solder.
2) Those that do not to solder.
Those that like to solder will solder both track feeders and rail joiners.