Re: new dcc HO layout
Although it is true that if you have 2 Five amp boosters the simple math says they add up to 10amps. However that is not what happens electrically.
That simplistic math ASSUMES the booster are wire in parallel and share the load such that together they can provide up to 10amps to a single locomotive.
Booster are use to DIVIDE up the layout electrically into to independent 5 amps sections for many electrical reasons. Boosters are meant to be “distribute" power around the layout.
1) Two much power consumed in a geographical are of a multilevel layout. Example a Engine facility and yard on level 1 and staging track above it on level 2.
2) Long Track bus runs well exceeding ~30 foot run length from the booster.
It is a "divided and conquer” electrical solution to large scale DCC electrical problems. Cuts them down to manageable sizes.
The electrical division of layout creates what is called a Booster Districts such that a given booster does not share track power responsibilities with other boosters. As a engine travels around the layout, it only powered by one booster at any time. Hence even if you have two 5amps boosters, the engine only receives a maximum of 5amps of power from one of them at any time. The only time the two booster come into electrical contact with each other is when a given engine cross the booster district boundary consisting or two double insulated rail joiners or gaps. When the engine completes the crossing, it back to a single booster for its power source.
Booster districts are not to be confused with power districts. Power districts are created by some kind of DCC circuit breaker that runs from a single booster. So each booster can have its own independent set of power districts subdividing it power.
So having two 5 amp booster does not make it a 10amp booster layout. It is still a 5amp booster layout just divided up into multiple 5A sections.
The only time you would need high current 8 to 10 amp boosters is if you have large scale locomotives such as O scale or G scale where the engines NEED that kind of power within a booster district. But the rules of how many booster you need remains the same as above.
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