Advice on power districts and breakers for Abbotswood Junction

[Phil Bullock]

We suffered a lot of down time at the recent Redditch show which I need to address. 
 

So a description of the layout… 27 x 12 ft, 20 boards. S1-S9 make up the scenic element, F1-F9 make up the fiddle yard and there is a joining board J1&J2. The ECoS controller sits on J2 at the south end. 
 

To protect ECoS I had installed two Cobalt IP-CB circuit breakers … one protecting a power district covering the scenic area and the other the fiddle yard. Both include track and accessory power. 
 

There are 14 cobalt digital point motors and 9 switchpilot servo accessory controllers on the scenic district and 40 cobalt Digital’s on the fiddle yard. 
 

The fiddle yard suffered worst! It felt like as we added more trains the IP-CB covering that district struggled to reboot. I discovered that by disconnecting the fiddle yard bus half way down it would reboot and stay live when fully reconnected, which suggests that even with the IP-CB set to a trigger current of 5 amps … we have a 7 amp ECoS … it was overloaded. Locos with stay alives perhaps? 
 

So my proposed action is to go from two districts to 4 … each protected by its own IP-CB.

 

These will be :

 

1. Accessory bus … a ring bus encompassing all 20 boards to seperate track and accessory power. 

2. Scenic bus covering track power only to 9 scenic boards 

3. Fiddle yard north bus covering track power only to north end of fiddle yard .

4. Ditto to south end of fiddle yard.

 

Will also add LED indicators to all boards for relevant buses.

 

What do folks think of this proposed approach? Note I am Sticking to proprietary options as I don’t have the time to build anything g myself …

 

Thanks in advance

 

 

Edited March 6 by Phil Bullock

[WIMorrison]

Join MERG and buy a pile of their DCO units, easy to build and very effective, this way you can split it up into lots of power districts - it is mostly the track that will need several districts

[Phil Bullock]

14 minutes ago, WIMorrison said:

Join MERG and buy a pile of their DCO units, easy to build and very effective, this way you can split it up into lots of power districts - it is mostly the track that will need several districts

Am in MERG but as I said I don’t gave the time to construct electronic units … the layout scenery, signals and rolling stock are more than enough!!!

[Dagworth]

36 minutes ago, Phil Bullock said:

Am in MERG but as I said I don’t gave the time to construct electronic units … the layout scenery, signals and rolling stock are more than enough!!!

Buy the modules, I'll build them for you. There are seven of them under Ipswich.

 

The other thing I've found really helpful is having switches that can isolate each of the power districts as well as the DCOs

 

Andi

Edited March 6 by Dagworth

[Phil Bullock]

14 minutes ago, Dagworth said:

Buy the modules, I'll build them for you. There are seven of them under Ipswich.

 

The other thing I've found really helpful is having switches that can isolate each of the power districts as well as the DCOs

 

Andi

Cheers! And thanks for the offer, but already ordered the extra IP-CBs this morning! Switches also good idea do you use double pole ? And before or after the DCO? 

[Dagworth]

1 hour ago, Phil Bullock said:

Accessory bus … a ring bus encompassing all 20 boards to seperate track and accessory power.

Do your point decoders also power the frogs from their accessory DCC supply or are they fed from a track bus for the frogs? 

If the former then a short from running an incorrect point still has the potential to shut down the accessory bus preventing the point being changed. 

 

I would also look at the viability of breaking the fiddle yard into 4 districts, Up high level, Down high level, Up low level and Down low level. That way a fault only shuts down one line.

 

Andi

[Dagworth]

2 minutes ago, Phil Bullock said:

Cheers! And thanks for the offer, but already ordered the extra IP-CBs this morning! Switches also good idea do you use double pole ? And before or after the DCO? 

Yes, double pole. For exactly the reason in my previous post, DCOs only operate single pole as a rule.

 

If you use a changeover type switch with a centre off then you can use one side of the switch to feed via a resistor to charge the caps in sound fitted locos before giving them full current as I mentioned at the show.

 

My switches are before the DCOs but it doesn't make much difference.

 

Andi

[Michael Hodgson]

16 minutes ago, Dagworth said:

Buy the modules, I'll build them for you. There are seven of them under Ipswich.

 

The other thing I've found really helpful is having switches that can isolate each of the power districts as well as the DCOs

 

Andi

Yes, they're easy kits - no sirface mount compnents which are a bit fiddly to solder.

 

The switches are also a good idea for fault finding on any big layout, even if you don't install cut-outs.  If there's a short smewhere, it's easy to localise the fault by turning eveything off and then turning them back on again one at a time.  If you have got the DCOs, the affected area will be obvious however, as its LEDs will change from green to red and the buzzer will sound.

[Phil Bullock]

3 minutes ago, Dagworth said:

Do your point decoders also power the frogs from their accessory DCC supply or are they fed from a track bus for the frogs? 

If the former then a short from running an incorrect point still has the potential to shut down the accessory bus preventing the point being changed. 

 

I would also look at the viability of breaking the fiddle yard into 4 districts, Up high level, Down high level, Up low level and Down low level. That way a fault only shuts down one line.

 

Andi

You are right! No seperate point decoders, integral to the motor and on the cobalt Digital the frog feed is from the same feed as the motor itself which will be the accessory bus. 

[Dagworth]

Just now, Phil Bullock said:

You are right! No seperate point decoders, integral to the motor and on the cobalt Digital the frog feed is from the same feed as the motor itself which will be the accessory bus. 

In that case a double pole switch on the track bus will enable you to totally isolate the track and so restore the accessory bus and change the point.

 

Andi

[Phil Bullock]

1 minute ago, Michael Hodgson said:

Yes, they're easy kits - no sirface mount compnents which are a bit fiddly to solder.

 

The switches are also a good idea for fault finding on any big layout, even if you don't install cut-outs.  If there's a short smewhere, it's easy to localise the fault by turning eveything off and then turning them back on again one at a time.  If you have got the DCOs, the affected area will be obvious however, as its LEDs will change from green to red and the buzzer will sound.

Cheers! The way we have the layout wired we can easily pull apart the bus connectors to achieve the same result … will install LED for each bus on each board when rejigging so that should help too… 

[Phil Bullock]

1 minute ago, Dagworth said:

In that case a double pole switch on the track bus will enable you to totally isolate the track and so restore the accessory bus and change the point.

 

Andi

Yep good plan!! Will just have to remember that when the accessory bus shorts to switch off the relevant track bus before resetting the accessory bus

[Bucoops]

Might be worth taking a leaf out the airline industry and have checklists? With people watching a failed layout it must be pretty high pressure at times. Not in the same league as losing an engine on an airliner but the principle is the same?

[Phil Bullock]

10 minutes ago, Bucoops said:

Might be worth taking a leaf out the airline industry and have checklists? With people watching a failed layout it must be pretty high pressure at times. Not in the same league as losing an engine on an airliner but the principle is the same?

Absolutely. Have already supplied driving checklist for each train movement and will do the same for power district resets. You are right about the pressure but @Downendian tells me he keeps his eye on me! Thanks Neil 😉

[WIMorrison]

1 hour ago, Phil Bullock said:

You are right! No seperate point decoders, integral to the motor and on the cobalt Digital the frog feed is from the same feed as the motor itself which will be the accessory bus. 

 

You don't need to use the IP digital 'frog feed'.

 

Use the SPDT switch that is available in the IP Digital with one pole fed from each side of the track (or track bus, I take it from the track at the turnout) and use the common to feed the frog.

[Phil Bullock]

2 minutes ago, WIMorrison said:

 

You don't need to use the IP digital 'frog feed'.

 

Use the SPDT switch that is available in the IP Digital with one pole fed from each side of the track (or track bus, I take it from the track at the turnout) and use the common to feed the frog.

That is very true! thanks for reminding me of that. It does mean more wiring though. Will try current plan but could fall back on that if problems persist. 
 

Of course given that all junctions on at least the scenic section are protected by signals then there should be zero incidents… 😀

[Phil Bullock]

Have been playing with IP-CB and stay alive sound fitted locos this morning. This has revealed that 0.33 amps should be allowed to give a safety margin for IP-CB to be able to reset after a short.  16 sound and stay alive Warships would not allow restart on 4 amps but they were ok with 4.5 amps.
 

 

Definitely a job for when SWMBO is out!!!

IP-CB will support more than that once they are running but it’s the power rush in to the stay alives that pushes up the current draw. 
 

As more locos are coming with stay alives installed this is something for folks to think about with their Dcc system perhaps ….

Edited March 8 by Phil Bullock

[Phil Bullock]

 

On 06/03/2024 at 13:44, WIMorrison said:

 

You don't need to use the IP digital 'frog feed'.

 

Use the SPDT switch that is available in the IP Digital with one pole fed from each side of the track (or track bus, I take it from the track at the turnout) and use the common to feed the frog.

 

On 06/03/2024 at 13:50, Phil Bullock said:

That is very true! thanks for reminding me of that. It does mean more wiring though. Will try current plan but could fall back on that if problems persist. 
 

Of course given that all junctions on at least the scenic section are protected by signals then there should be zero incidents… 😀

 

So have decided to do as suggested to eliminate another issue going forwards … thanks @WIMorrison

[5BarVT]

That’s a lot of Warships!

Paul.

[Bucoops]

6 minutes ago, 5BarVT said:

That’s a lot of Warships!

Paul.

 

Don't tell Russia ;)

[Phil Bullock]

12 minutes ago, 5BarVT said:

That’s a lot of Warships!

Paul.

Only half of them!!! 😉

 

6 minutes ago, Bucoops said:

 

Don't tell Russia ;)

Yes probably more than in the Black Sea fleet… 

[Enterprisingwestern]

3 hours ago, 5BarVT said:

That’s a lot of Warships!

Paul.

 

Correction.

That's not enough Warships'

One can't have too many!!

 

Mike.

[Phil Bullock]

2 hours ago, Enterprisingwestern said:

 

Correction.

That's not enough Warships'

One can't have too many!!

 

Mike.

 34 NBLs might be too many! Luckily we dont have that many…

[5BarVT]

2 hours ago, Enterprisingwestern said:

 

Correction.

That's not enough Warships'

One can't have too many!!

 

Mike.

More of a Western fan myself.  Can’t have too many of them.

Paul.

[Michael Hodgson]

6 hours ago, 5BarVT said:

That’s a lot of Warships!

Paul.

More than the Royal Navy!