Uso of Circuit breakers in a DCC ECoS/TC Gold Layout

[Anthony Ashley]

I am creating a large N gauge layout 35 feet by 16 feet. I have a thread at :

 

http://www.rmweb.co.uk/community/index.php?/topic/71151-north-welsh-coast-railway-welsh-dragon-rail/

 

Due to the size of the layout it will be too expensive to place track detection devices on the whole layout. My plan is to automate the main lines, non scenic hidden areas and first large storage area of each yard (the stations include Conwy, Penmaemmawr and Bangor), but to leave the rest of the goods area under manual control.. This will facilitate manual ops, including shunting in those goods yards.

 

The problem I have is how to integrate a fault detection system using ECoS II and TC Gold, automatically on the detection of a fault, but still provide a indication s located. If I can se up circuit breakers for each of the goods area I will be able to isolate the fault to within the area fed b y that circuit breaker. There are 2 options which may be possible.

 

1. A circuit breaker which shuts down before the computer ie TC Gold/ECoS system shuts down or 

2. Both the Computer system ie ECoS/TC Gold system shut down at the same time as the circuit breaker. I then reactivate the system, but the fault has been isolated by the circuit breaker which is still shut down. This will only work if the Computer system can be reactivated while the fault remains under the circuit breaker

 

Can anyone advise as to whether either of these are feasible options, and if so what brand of circuit breaker is recommended. 

 

Thanks for your assistance.

 

Regards,

 

Anthony Ashley

 

[AndrewC]

I am creating a large N gauge layout 35 feet by 16 feet. I have a thread at :

 

http://www.rmweb.co.uk/community/index.php?/topic/71151-north-welsh-coast-railway-welsh-dragon-rail/

 

Due to the size of the layout it will be too expensive to place track detection devices on the whole layout. My plan is to automate the main lines, non scenic hidden areas and first large storage area of each yard (the stations include Conwy, Penmaemmawr and Bangor), but to leave the rest of the goods area under manual control.. This will facilitate manual ops, including shunting in those goods yards.

 

The problem I have is how to integrate a fault detection system using ECoS II and TC Gold, automatically on the detection of a fault, but still provide a indication s located. If I can se up circuit breakers for each of the goods area I will be able to isolate the fault to within the area fed b y that circuit breaker. There are 2 options which may be possible.

 

1. A circuit breaker which shuts down before the computer ie TC Gold/ECoS system shuts down or 

2. Both the Computer system ie ECoS/TC Gold system shut down at the same time as the circuit breaker. I then reactivate the system, but the fault has been isolated by the circuit breaker which is still shut down. This will only work if the Computer system can be reactivated while the fault remains under the circuit breaker

 

Can anyone advise as to whether either of these are feasible options, and if so what brand of circuit breaker is recommended. 

 

Thanks for your assistance.

 

Regards,

 

Anthony Ashley

Interesting project. Lets start with some semantics. What exactly do you mean by fault?

 

If you mean simply a current overload (short, too many things drawing current in an area, running the wrong way through a point causing a short, etc) then something like a circuit breaker is the correct route to follow. I've junked my old Digitrax PM42 and replaced it with 4 PSX Powershield breakers. http://www.dccspecialties.com/products/powershield_x.htm With the computer and a stationary decoder that can read inputs (Digitrax DS64 for example) its possible to have the breaker trip on a short and report it back to your computer. Alternatively if you have the logic built into your block detection its also possible to have the computer send a power off command to an individual PSX when something enters the wrong block or if you need to trigger an emergency stop to one part of the layout but without stopping the whole thing.

[Anthony Ashley]

As requested more information.

 

I am talking about shorts. The reason for using circuit breakers is to avoid putting in track detectors in the goods yards, except in the first storage yard area sufficiently large enough to hold the majority of the goods rakes. 

 

The circuit breaker should be cheaper than the detection hardware.

 

Thanks for the reply. How do you get the circuit breakers to trip without tripping the computer.

 

Regards,

 

Anthony Ashley

[AndrewC]

As requested more information.

 

I am talking about shorts. The reason for using circuit breakers is to avoid putting in track detectors in the goods yards, except in the first storage yard area sufficiently large enough to hold the majority of the goods rakes. 

 

The circuit breaker should be cheaper than the detection hardware.

 

Thanks for the reply. How do you get the circuit breakers to trip without tripping the computer.

 

Regards,

 

Anthony Ashley

Sounds simple enough. The circuit breakers act against just the section of track that has the short. Basically you double gap the area that you want to manage, and feed the power from the power manager. The link I put in the first message has another link to the manual.

 

 If you don't provide any feedback from the breaker the command station and computer will not know of the power outage. The breaker, or more correctly power manager handles the power off/on for the section. Its fairly straightforward to set the current limit on the power manager. In the most simple of terms, the power manager pulls the plug on the affected section of track without causing the whole layout to power down.

[Gordon A]

The use of circuit breakers for various sections so that a short circuit does not trip out the control system is a good idea.

My problem is that my DCC unit reacts a lot quicker than the circuit breaker, so I would try one unit before making any bulk purchases.

 

The other option is to use an old trick of running each section in series through a car bulb which is of a high enough current onsumption to absorb any excess current caused by the short circuit.

 

Gordon A

Bristol

[PaulCheffus]

The use of circuit breakers for various sections so that a short circuit does not trip out the control system is a good idea.

My problem is that my DCC unit reacts a lot quicker than the circuit breaker, so I would try one unit before making any bulk purchases.

 

The other option is to use an old trick of running each section in series through a car bulb which is of a high enough current onsumption to absorb any excess current caused by the short circuit.

 

Gordon A

Bristol

Hi

 

I had to change the reaction time on my NCE EB3s so they would trip before the Lenz LVZ100. Do your ciruit breakers have the option to change the delay time?

 

Cheers

 

Paul

[Crosland]

As requested more information.

 

I am talking about shorts. The reason for using circuit breakers is to avoid putting in track detectors in the goods yards,

This is the bit that confuses me. What do you mean by track detectors?

 

You don't use a circuit breaker for occupancy detection and vice-versa you don't use occupancy detectors as circuit breakers. They are different solutions for different problems.

 

Andrew

[Anthony Ashley]

Andrew,

 

I can't afford to put occupancy detectors on the whole of the layout. If there is a short in an area which is controlled by an occupancy detector I understand that by careful wiring you should be able to isolate the fault. If I can't afford to put detectors on all parts of the layout, I need some other way to isolate faults. My preferred method to isolate faults is circuit breakers which will isolate the fault to a particular area. It appears from this discussion that you can play around with the variables in a computer system to change the trip current relevant to that controller. Alternatively if I know the trip current for the computer control I could set the trip value for the circuit breakers at a slightly lower level, therefore isolating the fault by the use of circuit breakers prior to the computer tripping the whole system, and leaving me with fault is located.

 

It seems both options may be available. If these assertoins are incorrect please reply.

 

Regards,

 

Anthony

[two tone green]

I think you need to tweak your understanding a bit.

 

The computer does not control the supply to your model railway, its the ECoS in your case. The computer is tells the ECoS what to do but the supply and so called trip current is all taken care of by the ECoS so its that you need to find out about.

[Anthony Ashley]

Two tone I agree with your comments but the outcome I am trying to achieve is the same.

 

Has anyone run the ECoS system using circuit breakers on a large layout and what is the preferred circuit breakers. One choice above is PSX.

 

Regards,

 

Anthony

[Edwin_m]

From what I read on the MERG forum, ECoS has a very quick cut-out which will beat most circuit breakers.  MERG have developed one that is fast enough but I don't think it's in production yet.  The other option is to have a separate booster for each power district with its own cutout, but that will be more complicated and expensive. 

 

As people have said, block detectors won't detect a short circuit.  Instead the relevant power district (or the whole layout if not divided into power districts) will cut out.  The block detectors may then just all show unoccupied although some types have extra logic to "freeze" their previous state (Littfinsky do this but Lenz need an extra module).  Either way TrainController won't know there is a problem and will carry on running and trying to drive trains.  You could provide a simple circuit that operates a feedback input according to whether the track power is present on a particular controller, and have TrainController bring trains in or approaching the area to a stop if power is lost.  This avoids trains taking off at full speed as soon as power is restored, but the "dead reckoning" used by TC to keep track of train positions is still going to be confused afterwards until each train has moved into a different hardware block detector. 

 

Nor is it possible to restore power and have the affected circuit breaker cut out to highlight the location of a short.  If the ECoS cuts out faster than the circuit breaker then the same will just happen again.  The circuit breaker loses power when the ECoS cuts out and when power is restored it doesn't have any memory that it was in the cut out state (and if it did then how would it "know" whether the problem had been cleared while it was powered down?). 

 

So the only answer is to find a compatible circuit breaker or use boosters, and sub-divide the layout enough that it becomes relatively easy to locate a short.  Interestingly block detectors do help in one way - if they are of the diode drop type you can check the layout by hand with a continuity tester (with track power off!) and the block section where the tester shows continuity is the one containing the short.   This is because the voltage drops across the detector diodes are larger than the low voltage used by the continuity tester, so it is effectively only testing one section.  You could do the same thing in areas not fitted with block detectors by sectioning the track and feeding each section through four power diodes connected as two series pairs, in parallel but with opposite polarities. 

[RFS]

Have a read of this - http://www.rmweb.co.uk/forum/viewtopic.php?f=10&t=42243

[Anthony Ashley]

Dear All,

 

I have read through a number of blogs on using circuit breakers with a DCC  computerised system and it certainly appears possible as explained above. Has any one used a MERG circuit breaker and how many sub power districts did it manage. I know PSX does one up to 4 sub districts or outputs.

[Nigelcliffe]

Dear All,

 

I have read through a number of blogs on using circuit breakers with a DCC  computerised system and it certainly appears possible as explained above. Has any one used a MERG circuit breaker and how many sub power districts did it manage. I know PSX does one up to 4 sub districts or outputs.

 

I remain confused about what you hope to achieve with a circuit breaker. 

If a computer is to do something with the overload information (a circuit breaker tripped), it needs that information fed back to the computer. 

And, as others have said, overload is not the same as occupancy. 

 

The MERG device is a single circuit device, cost approx. £10 in kit form.  It detects current overload on a single output.  There is a connection on the board which could be used to signal that the overload is occurring, and thus feedback the overload information to another system (eg. computer), but you'd need to add hardware to convert this output to something a computer can utilise.  There is also an external control switch input to the board which can be used to lock the output to "power off".   

The output can be 0.75, 1.5 and 3A, and the speed of cut-out can be set with various jumpers.  (The 0.75A option comes from winding the sensing coil with two turns of wire, giving jumper options of 0.75 and 1.5A, rather than 1.5A and 3A, not sure if that trick will make the production instructions, though it was found in testing).  I built one of the pre-production test kits for MERG to find bugs in the instructions, and the production kits are due within a few weeks, possibly days.   I haven't tested the MERG unit on an ECoS, though its possible that someone else has.  If I get round to visiting my ECoS owning friend, I might be able to report on which cuts out first.

 

 

-  Nigel

[Anthony Ashley]

Nigel,

I understand the issue raised, however given the size of the layout I do not consider I can afford to automate all of it, or essentially not for some time. Therefore if some sections of the layout do not have detectors or other hardware hanging off it I understand that thosae areas will not get computer feed back. I intend to fully automate the main lines, hidden areas and the first large peice of track into the 3 goods yards planned ion order to automate the goods ops on the main line but retain manual operatoin for shunting. I intend to use tube and wire point operatoin in those areas of the goods yards. This will facilitate my time table and automatic operation around the layout on the scenic main lines to the hidden non scenic areas under the scenic section. I still need a means of fault detection in the non automated part of the layout (where shunting operations will occur). Incoroporating circuit breakers into these goods areas seems the cheapest option for fault detection.

 

Thanks for the advice on the MERG unit. I need to ascertain if they work in conjunction with ECoS. I know the PSX  breakers are as  a reply above has had success.

 

Regards,

 

Anthony