Gavin's DCC Power Issues.

[Chrissaf]

But then add in a second 15v ac supply direct to the track ?

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Absolutely NOT ... ONLY the eLink DCC track output MUST connect to the track.

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If you want more track current, then upgrade (replace) the standard eLink 1 amp power supply with the Hornby P9300 4 amp power supply.

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Is there a circuit diagram I could follow ?  Not sure how I get the dcc signal from my e link without also the power from my e link ?

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You will only need a Booster if you want to run more than about 10 x locos simultaneously. Up to 10 x locos can run on the upgraded 4 amp supply mentioned above.

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You don't seem to grasp the basics of how DCC works. The DCC signal is not a separate entity from the power. The DCC Signal is the track power.

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A Booster does not add more current to an existing power domain. In other words, adding a 4 amp Booster to a 4 amp powered eLink does not give you 8 amps of current on the same track. A Booster is more accurately a 'DCC Repeater'. It takes a DCC Signal feed from the main track output of the eLink controller and 'repeats' the DCC signal (makes a synchronised copy of that signal) to feed on to a completely separate track section using the current from the second 4 amp power supply.

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Thus you have two power separate power domains that are insulated from one another. Each domain has its own 4 amp limit, but no domain has an 8 amp total current available to it.

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In simplistic terms a domain powered by a Booster could be a second track loop or oval.

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[Chrissaf]

I use my Elite on a number of stand alone layouts and successfully and safely use appropriately rated laptop power supplies (permanently wired into the layouts) in addition to the Hornby one supplied with the Elite. Toshiba make some 15 volt 5 amp supplies with, as luck would have it, a jack plug of the correct dimensions and polarity. These can be picked up on a well known online auction site for about £10.

 

[Chrissaf]

These two Gavin posts have been moved to and combined here from two different threads that were hijacked.

[Chrissaf]

Supplement to my first reply.

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This is in very simplistic terms how you would deploy a Booster, but as said before. Your layout is unlikely to need the complication of a booster (at least for the track) unless you want to run a very large number of trains simultaneously. You split your layout up into a number of logical sections, each section becomes a 'Power Domain' and each domain is isolated from the others using Insulated Rail Joiners. Each 'Power Domain' has its own Booster that 'repeats' the DCC signal from the single controlling eLink. Only one Booster shown in the drawing for clarity.

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Where a Booster can be a useful addition. Is if the layout is going to have a very large number of points and DCC accessories and you need the extra current to operate those via a larger number of Accessory Decoders - see this image below instead. This solution is particularly useful if you are planning to use high power consumption accessory decoders such as those made by DCC Concepts.

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/media/tinymce_upload/b7b04b94a572556075a7fea596e69a47.jpg

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[96RAF]

The problem is the way DCC was developed. Originally there would be separate boxes for power (supply) booster, command station, controller, accessories, etc. In those days if you wanted more power you swapped your little booster box for a big booster box. The same holds true today but the command station and controller are now all in one and the power supply is either a plug in wall-wart low amp unit or a hi amp PC PSU brick type of unit.

 

The word booster has taken an old new meaning and misused it to the point the Elite even has terminals marked BOOST which folk think means you can connect these to the track for more oomph. Unfortunately if you do that the oomph comverts to smoke and the Elite dies.

 

Chris has clearly explained that a Booster is a actually signal repeater - look at the Hornby device - it is called a Power and Signal Booster. Close enough to the truth. Download the Hornby Booster manual and look at how it connects between power districts or domains as Chris calls them and the whole logic of boosting should become clearer.

[Gavin the Drummer]

Thanks chap,  very clear, I understood the DCC signal was the power but could not  figure out what to do if you used up your power supply.

ive purchased the 4 amp power supply and won't be going up to 10 Locos any time soon

much appreciated

ps this is the first time I've ever used a forum ( for anything ) so sorry I didn't post my question direct,  I'll know in the future.  You've both been very helpful 

Gavin