z21 - Will i need a booster?

[WIMorrison]

The accessory bus has to be taken from the command station otherwise there are no DCC commands to control anything :)

 

for the DR4018 you can have a separate power feed which can be basically anything you want from 12v DC 3a upwards, though I just use my accessory bus direct from Z21 as track bus is fed by a separate Z21 booster

[Junctionmad]

Just in relation to ABC. You can get issues where metal wheels in the stock following the loco bridge the ABC track section and non ABC sections , causing errant behaviour and failure to stop. 
 

I’ve had to place very short insulated sections in between the two sections to prevent such issues , but it’s not a complete success , double heading ,carriage light pickups can all cause confusion 

[Oldddudders]

22 hours ago, Ron Ron Ron said:

”DCC can be as simple, or as complicated as you want it to be....”

And that message needs to be stressed to every newcomer to DCC. While the OP asked a very simple question, the temptation for the knowledgeable to branch off into further complexities is invariably too much, and it is easy for the less-technical of newcomers to be totally overwhelmed. 

 

I urge the OP to take things one step at a time where DCC is concerned, which gives a fighting chance of everything doing what you expect. Get the basic installation in and working, then look at the optional bolt-ons, which may need to include an additional booster (don't forget that command stations almost invariably have a booster built in, putting out the stated power), but probably won't. And, with the track layout proposed, I bet you will find running four locos at once requires a second brain!

[Pete the Elaner]

2 hours ago, Oldddudders said:

And that message needs to be stressed to every newcomer to DCC. While the OP asked a very simple question, the temptation for the knowledgeable to branch off into further complexities is invariably too much, and it is easy for the less-technical of newcomers to be totally overwhelmed. 

 

I urge the OP to take things one step at a time where DCC is concerned, which gives a fighting chance of everything doing what you expect. Get the basic installation in and working, then look at the optional bolt-ons, which may need to include an additional booster (don't forget that command stations almost invariably have a booster built in, putting out the stated power), but probably won't. And, with the track layout proposed, I bet you will find running four locos at once requires a second brain!

 

I wonder how many have been put off from trying DCC after asking a simple question then having all sorts of complicated extras thrown into the discussion?

[RobinofLoxley]

In this case, the OP is already contemplating a fairly ambitious layout. He is not going to be put off by any discussion about future options, pitfalls, etc etc, in my opinion.

[Brian]

I placed this on another forum. It shows the very basic idea of a dual DCC Bus...https://postimg.cc/4m2r5CX6

[KingEdwardII]

@Robin,

 

The power supply for the accessory bus on my layout is currently a 12V DC supply redeployed from an old piece of computer equipment. I use this to feed the Power terminals of the DR4018 units, which actually drive the point motors. The DCC control signals for the DR4018s come from the power bus at present.

 

However, this is only a temporary arrangement - I am moving towards computer control for the accessories and this will involve a separate low-cost DCC controller driving the accessory bus, like a SPROG, with a Raspberry Pi issuing commands via JMRI driven by a touch screen display.

 

The current wiring on my DR4018s is shown in the picture. The power bus is at the top, the accessory bus at the bottom and the connections to the MP1 point motors are the various white 3-core flex cables.

 

Mike.

[RobinofLoxley]

Thanks. I assumed you had an auxiliary power supply. I am just noting the OP's original question, and the various ways it has and hasn't been answered. I'm not competent to make a list and be 100% sure it would be correct. There aren't that many possibilities.

[dpgibbons]

A circuit breaker in the track circuit set to something less than 3A is a good idea anyway - you would not want max power flowing through an unattended short.

[Crosland]

13 hours ago, dpgibbons said:

A circuit breaker in the track circuit set to something less than 3A is a good idea anyway - you would not want max power flowing through an unattended short.

 

If the booster doesn't shut down on a short then either it's not a short, the booster is faulty or your wiring is not up to scratch.

 

Circuit breakers are useful for splitting the layout into different power districts so that a fault in one does not bring the whole layout to a halt. Using it to isolate track and accessories is one example of this.

 

It's a waste of money to simply replicate a boosters own current limit.

 

If you are using a booster with a stupidly high current limit then there may be a case for multiple circuit breakers but this comes under power districts, see above.