||Planning Considerations: Power and Wiring
How Many Track Boosters Do You Need?
Surprisingly, it is not the amount or length of track that determines the number of boosters.
It is the quantity of locomotives occupying and being powered by the booster, at the same time, that determines the number and type of boosters required.
Although a single booster can drive your entire layout, a derailment will shut down the entire layout.
It is much better to use additional boosters each driving their own “center of operation” such as a town or yard.
You can start with one booster and when your budget permits, add more boosters.
This section describes some of the options and considerations when estimating the location of the boosters and the zones they power.
A Block is a section of track that is electrically isolated from other track sections.
A single block can be as simple as the main line.
A block can also be a complete town or yard facility.
A block can also be called a zone.
A gap is a physical cut in the rails.
Gaps are cut with a small cutting disk.
Both rails must be gapped and the gaps are parallel to each other.
Never stagger the gaps.
Temperature and humidity changes can cause gaps to close.
This usually occurs as seasons change.
A small piece of plastic trimmed and glued into the gap will help keep this from occurring.
Insert the plastic and cement in place using epoxy glue.
File the plastic flush with the rails.
Roll a car over the joint and verify nothing catches, bumps or otherwise obstructs the wheels.
To check the that the flangeway is clear, gently push the wheels sideways and feel for any bumps.
If any are found, remove them with an X-acto knife or file.
The reversing section or reversing loop is a track configuration that literally reverses the direction of the train.
In other words, the train goes into the reversing track and comes out of the reversing track headed in the opposite direction.
Loops and sections can be difficult to locate and are a constant source of headaches.
Eliminate them wherever possible.
Where To Block?
The total number of blocks on your layout determines the number of independent boosters that are needed.
When evaluating layout blocking, think in terms of what your block is providing.
Is the block to prevent one operator from interfering with another operator; is the block needed so that power is not diverted to other parts of the layout.
These two concepts are basic to effective block definition: blocking for isolation or blocking for power.
Blocking For Isolation: This is relatively easy to figure out.
In the drawing below, the town is divided into two separate zones or blocks; the red zone is inside the town, and blue zone which is the main line.
If two operators are working in a town, one operator performing local switching moves in the town and another passing through on the main line, you do not want a derailment or short inside the town to shut down the main line.
Separating the town and the mainline into separate zones isolates both operators and solves the problem.
In this example, a ZoneMaster Dual is used.
If the passing siding is heavily used as part of the mainline operation, they it should be part of the blue zone.
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Blocking For Power: Sound decoders consume an enormous surge of current when power is first applied to the rails.
Sometimes the current surge exceeds the capacity of a single ZoneMaster and trips the short circuit protection.
Common locations for this problem to occur are staging tracks with many parked but powered trains and locomotive servicing areas in large mainline yards.
A simple toggle switch to kill power to tracks is one way to solve the problem.
A power indicator LED is recommended for each track or group of tracks fed by the cutout switch.
Long linear yards that use an operator on each end should be split near the center.
In other words, the yard is split vertically creating a left and right center of operation.
This is best for this track design because the two yard switchers tend to work at opposite ends, pushing long cuts of cars towards the yard’s center.
There is seldom much power being consumed in the center and the bulk of the turnouts are at each end.
One concern with this design is with cars that use metal wheels.
If your cars use metal wheels, you must ensure that the block boundary gaps are never bridged by the metal wheels when the car is stopped.
If a metal wheel bridges the gaps, the two blocks are now in parallel and isolation is lost.
The yard below is too short to allow a vertical separation.
For this example, a horizontal separation is recommended.
The natural split is between the engine servicing facility at the top and the classification yard.
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