Booster

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Short Definition

The Booster is an electronic device that takes instructions from the Command Station, and creates the digital signal supplied to the track.

Some Digital Command Control systems combine both the command station and booster in one package. For this definition, the booster is a separate device which requires instructions from a command station. It requires two inputs to function: a data stream from the command station, and power from the power supply. The output is a digital waveform that is supplied to the track. It really functions as an amplifier, taking a digital level signals from the command station and amplifying (boosting) them to track level voltages.

The booster is sometimes referred to as a the "Power Station". Since the booster contains no intelligence (non-thinking), it can be thought of as the "Pack Mule" of a DCC system as it is responsible for combining the intelligence from the command station with the power from the power supply. Some boosters may not have autoreversing, where others do.



Booster Power Regulation and Protection

Boosters are responsible for the following tasks:

1) Convert the incoming AC or DC power into a local internal DC power source suitable to drive the track.

2) Provide short circuit protection, so any short circuits will trigger the circuit breaker to cut power to the track before something is damaged.

3) Optionally provide a regulated voltage for the track.

4) Provide an automatic resetting "Circuit Breaker" function.

5) Convert the command station's digital level signals into a DCC track waveforms with suitable voltage and current to run locomotives.

Additional Boosters

You might think it's best to have a single, large, booster/command station to power your entire layout. However, you will soon learn, it's typically best to have a couple smaller boosters distributed around your layout. The reasons include: Additional trains, reverse sections, and to isolate derailments.

Adding Boosters

To add additional boosters, you will need to electrically divide your track into power districts, and connect a new booster to that section of track. The booster may need a separate power supply, and must be connected to your DCC system's booster bus. By connecting the booster to the booster bus, all boosters on the layout will send out the same commands to all sections of the track. This allows trains to recieve commands, even if they are crossing between power districts controlled by different boosters.

Suggestion: Be sure to double gap the tracks to fully isolate the boosters. That is, both rails need to be cut at the same spot.

  • If the train stops at a gap, the boosters may be out of phase. Reversing the track power connections on the booster can correct that issue

Warning: Do not wire boosters in parallel. This will lead to melted plastic and fried boosters. You cannot simply wire them in parallel. You must connect separate sections of track to separate boosters.

Caution: Read and follow the manufacturer's directions for the booster and your DCC system on how to properly wire an additional booster.

Common Ground: Be sure to wire a common ground between boosters. This way they all have the same reference point for ground. Power management devices may also require grounding to the command station or booster. This can also function as a return when current needs to return to the source.

This ground is not the same as the ground provided by your house wiring. You should never tie the low voltage side of your DCC system to house ground.

Additional Locomotives

A booster is rated for amount of current it is capable of delivering to the track. If you demand more current than it can supply, it will simply shutdown.

If you notice the trains are starting to slow down when multiple trains are running, that's a sign you are reaching the limit of your booster - it's time to add additional boosters.

Typical boosters deliver 4 to 5 amps, and can be as high as 10 amps. This may be enough to run a train or two in the garden, or almost a dozen HO or Z scale trains.

Isolating Derailments

Sooner or later, a train will derail causing the booster to go into protection mode.

Once this happens, all trains using that booster will come to an immediate stop. If you want to prevent a derailment, say in a switching or staging yard, from stopping all the trains on a layout, power these sections with a separate booster. This way, if someone accidentally shorts the tracks while putting locos on the tracks, the rest of the layout will continue to operate.

Alternatives

There are alternatives for adding boosters to get the above listed features, except for adding a booster for additional power.

If all you need to do is isolate a small section of track, or run one or more Reverse sections, then you can use power management modules from various manufacturers.

These modules typically go between the booster and the section of trackage (power district).

For example, a reversing power module would connect between the booster and a reversing section, but the rest of the track is still powered directly from the same booster. The moment a wheel connects between rails of different polarity, the reverser springs into action and makes them both the same polarity. A typical application would be a reverse loop.

Some power management modules can take a single or multiple inputs, and provide multiple outputs. This splits up your layout into several power districts using a single booster.

Stationary Decoders

A booster can also be used to create a dedicated bus for stationary decoders, isolating the stationary decoders from events occurring on the track. This is a useful method if the stationary decoders employed lack the ability to connect to a throttle network such as LocoNet or XPressNet.

Wiring

See the instruction manual for instructions on connecting the booster, and any additional boosters.


See also