Power boosters

[Cloggie]

Hi all, thanks for previous help regarding points and PADs.

I've now got the display progressing to the point of burning my fingers with solder, the layout passes the ‘rule of thumb’ frequently mentioned in that it’s 40 ft x 12 ft occupying a converted loft room and it’s now got 60 points, and that’s without another set of about 8 in an oil storage facility, along with a turntable to power.

I’d looked at the bewildering explanation of the Hornby PAD online to see if I could link two points to work simultaneously. This was because I had areas of parallel tracks where I needed double sets of points to take trains from one to the other in either direction they travelled simply as trains started at my entry position and then had to be routed through to the inner loops. (This is the case for 14 pairs of points on other parts of the layout to get trains from starting positions to one of several loops.).

Anyway, reading it left me hearing a whoosh sound overhead as it left me for dead. So an experiment showed I had ability to put two R8247 points into each connection point of the PADs and they operated with ease so that was solved.

I’m now wondering whether to have a separate booster for the points (and their signal leds) due to the size of this layout. I’d originally planned to separate the layout into areas. Those areas with large amount of points, plus say, turntable, having one booster, other areas having boosters to help deal with multiple points and signal leds! plus being able to handle large train loads, but now wondering if it’d be better to place all points (& signal leds ) on one or two booster(s), and then separate track boosters for track taking in other areas. Anyone had any experience of best way to distribute the power on a layout this size. All comments gratefully received.

[Chrissaf]

In order to give more accurately targeted advice. Can you provide just a little bit more information please.

1. What DCC Controller are you using
2. What amperage is the controller power supply.
3. Confirmation that all Accessory Decoders are Hornby R8247 and how many currently and how many planned for future growth.
4. What track & points .. Hornby or PECO or other ... if PECO are they Electrofrog.
5. If PECO Electrofrog ... are you deploying the 'full frog power switched' modification.
6. If the full frog power switching mod is deployed what are using for the electrical switching [as this is not supported directly by the R8247 decoder].
7. Are all signals run directly off the Accessory Decoders or are any signals switched via auxiliary contacts attached to the points [see also Q6 above].
8. How many expected maximum concurrent train movements do you envisage running on the layout.
9. Do you use sound decoders?
10. Are there any other power loads not mentioned so far. Carriage lighting for example?

[Cloggie]

Hi Chris. Thanks for responding. I’ll do my best to go through the list of questions in next couple of days ( builders in causing a delay in response). Thanks for help.

Bry

[Cloggie]

Good after Chris.

live got a Hornby Elite giving 3 amp. All decoders are Hornby R8247’s and there are 12 of them. All track and points are Hornby. I’ve had a good walkthrough of the display today and it boils down to having 60 points, 14 operated in pairs. And two which are for future use. At each of these sets of paired points I intend to wire some red/green leds to indicate there positions. There’s a separately controlled area with a turntable. I intend to run up to 40 trains at once, many double headed or with long wagon loads, so expect them to be power hungry, and to help I’ve got most of the tracks level. At least 16 of these locomotives have sound decoders installed. I’m veering toward breaking the display into about 6 separate areas and putting in boosters to isolated track, after looking at the point positions. Other option is to put boosters into each track isolated at crossover points to other lines.

I wish I could download a schematic of the layout which would help you to gauge what’s being planned.

[Chrissaf]

There is nothing to stop you from posting a schematic or image.

.JPG .PNG and .GIF file formats are supported but not .BMP or Apple's proprietary image file format. 'How to' is TIP number 4 in my Forum TIPs page.

TIPs on using the forum. :: Hornby Hobbies

A total of 12 x R8247's would definitely benefit from having a 'Power Domain' via a booster dedicated for them. Fortunately [or unfortunately depending upon your point of view] the R8247's do not have very powerful CDU's in them, thus their 'in-rush charging currents' are relatively low compared to some other brands of decoder.

Forty concurrent train movements would also benefit from having multiple power domains as well. But this needs careful design based upon an understanding of the planned train movement schedules within the layout i.e where in the layout will trains bunch up in their movements as ideally they need to be evenly distributed across the available power domains.

If you had been using RailMaster as your controller, then you would have had the option to use a dedicated second controller for operating points and signals. As you are using an Elite, then that RM option is still open to you. But if you only use the Elite as a single controller [with or without Boosters] then you do not need to be overly concerned with my unanswered questions about Electrofrogs. If you do use Electrofrogs with fully switched frog power, then just be aware that the switched power to the frog needs to be sourced from the same Booster output powering the track section that the Electrofrog point is physically located in.

The schematic below is just an overview of how Boosters could be deployed in principle. The Hornby R8239 Boosters are now discontinued with no known planned replacements. So you will have to look at other Booster brands. Personally, I would try and avoid the USA derived booster products as they tend to have much higher track current booster products that don't really suit the UK and Euro markets.

[Cloggie]

[Cloggie]

Thanks for the help Chris most appreciated. I’ve now got it sorted ( I think ). I’m using the Elite for one track loop, Each track loop being isolated from others at crossover positions by the point pairs. It’s then set up as another five boosters, each on isolated track loops, plus one booster solely for all the points. Then there’s a reverse loop module through a switch to use on one reverse loop and occasionally on the turntable. Fingers crossed.