Double reverse loop, DC/DCC operastion and option for DC autoshuttle.

[beavercreek]

As My loco fleet is still semi DCC chipped and I wnat to carry on having the option of the auto-shuttle line operating under DC. I have had to think hard how to convert the line to a double autoreverse loop with shuttle option.
The autoreverse loops will also operate under DC or DCC using the Massoth 8157001 module sensor arrangement. There will be a multipole switch to change the module power wiring from DCC to DC (also the module's DC operation needs its own little power supply).
Because of the DC reverse loop operation, two modules are needed.

Below is how I want it all to operate, so if any of you have had experience with double reverse loops I would be glad for anything to watch out for. I wonder if anyone has had experience with DC usage???

The DC shuttle has been slightly reconfigured from its present operation but will roughly follow the same journey. All of the shuttle and even spurs are outside the reverse loop sections between the module sensor/breaks so they are not really affected, as such, by the the new reverse loop additions....I hope...

The reverse loop stuff is in red and the DC shuttle in green

 

[Zerogee]

You don't believe in keeping it simple, do you Mike?

My only advice would be that if control mode selection requires MORE than one switch or control to be operated, then check ALL the most stupid scenarios of getting said switches wrongly positioned, to make sure there is no chance of anything seriously shorting out/blowing up/whatever - because if there IS a way of it going wrong, you can count on someone to find that way sooner rather than later.....
Good luck, hope it works!!

Jon.

 

[beavercreek]

Well Jon, you know me...I always enjoy a challenge..
The points will be set so that they do not need to be changed and that the exiting train will 'force' the blades (all pilots on steamers and rolling stock will have to weighted to make sure that this occurs.
At first I will test the two loops all out with only DCC operation before bringing in the DC option
I am thinking of running a long multi-core cable up to Arrowhead 'small loop' and to the Beaver creek 'big loop' to enable DC/DCC auto-reverse loop operation to be switched in from the same place as where I swap the layout power supply between DC/DCC. In fact the autoreverse multi-switch will be side by side and easy and clearly marked. So hopefully as I will be the one setting the power, I will also see the autoreverse module setting at the same time............

I will get the auto-reverse loops operating perfectly first and then 'add-in' the shuttle system.

On getting around to adding the DC auto-shuttle back into the equation:
The two auto-reverse modules' multiswitches (the ones sited next to the power supply switch) will be swtiched to off completely if the DC auto-shuttle is to be used.
When the auto-shuttle is being is being switched 'in' (again only with DC power from the supply), the same switch will also isolate the entry to the 'Big Loop' as well as the module sited there so that takes out any problem with the module connections.
The auto-shuttle will just act as it has done since day one of the line. It will have the option of going from Arrowhead to Pointrock instead, but as far as it is concerned it just blindly goes about its business.

Now I say all this....but as I am connecting up the loops as just plain DCC to begin with.......I may just stay with that and investigate using a Massoth 'feedback' unit to get a shuttle operational under DCC as well....we shall see......

 

[Zerogee]

Sounds all well-thought-through, Mike - fingers crossed....

Jon.

 

[dutchelm]

You may make it idiotproof, but never underestimate the intelligence of an idiot.

 

[Zerogee]

You may make it idiotproof, but never underestimate the intelligence of an idiot.

Exactly - the version of that I've always liked is "Make something idiot-proof, and Nature will build a better idiot...."

Hence my preference for single multi-way switches wherever possible, so that you physically CANNOT select the "wrong" combination of settings even during the most serious brain-f*rt moment!

Jon.

 

[Zerogee]

I do know that if you run an analogue loco on zero and it runs into a reverse loop in DCC mode it will stay in the reverse loop and shuttle back and forth between the rail isolators.......

Heheheh..... yes, I suppose logically it would! Do LGB or Massoth actually warn you of this in the reverse unit instructions?

Jon.

 

[Tony]

Good luck Mike my brain hurts just looking at your map but i'm thinking the Principle of KISS .......................Keep it simple stupid can you not have it all dcc with a battery shuttle....i Havnt thought about the switching yet but its a plan for the future.....do look forward to seeing you improvements thou soon

 

[beavercreek]

Good luck Mike my brain hurts just looking at your map but i'm thinking the Principle of KISS .......................Keep it simple stupid can you not have it all dcc with a battery shuttle....i Havnt thought about the switching yet but its a plan for the future.....do look forward to seeing you improvements thou soon

How did I know that you would say that Tony?
As I said at the beginning, a good deal of my locos are not chipped and I would like to have a selection of them to use on the reverse loop line.
I have a battery one or two and they will obviously work fine as they are not affected by any track polarity so that is why I didn't mention battery running.
As far as switching is concerned, I am okay with that, as it will practically all happen where the power supply/central station are sited. I will be using rotary multi-pole switches much like the ones (except for lower rating) that I have used for the switchover from DCC to DC power

 

[beavercreek]

You may make it idiotproof, but never underestimate the intelligence of an idiot.

Exactly - the version of that I've always liked is "Make something idiot-proof, and Nature will build a better idiot...."

Hence my preference for single multi-way switches wherever possible, so that you physically CANNOT select the "wrong" combination of settings even during the most serious brain-f*rt moment!

Jon.

Oh you of little faith....
I know that my idiot quotient can be known to spike on occasion but as the control switches will all be side by side and clearly marked, even when under the influence of an 'idiot spike' I should be fine.

 

[beavercreek]

Hi Roly
Thanks for the tip.
Peter at Massoth has said that you have to have two modules (one at each loop) if there will be any DC running. It would be simple to switch out the second module when operating DCC , if there are any probs like you have experienced.

The reverse loops are at either end of the single line so only one train will ever operate.....and I will now make extra sure that all track work is totally tickety boo!

 

[don9GLC]

I have not personally used the Massoth reverse loop modules but my understanding is that they are designed to operate completely differently on DCC and DC. With DCC the module switches polarity in the loop but with DC it is the main line polarity that is switched.

It's not impossible to arrange to switch all the necessary connections but it does not seem to be simple. If you only operate one train at a time it might be possible to operate DCC with the DC wiring connections (switching the main line polarity) but as mentioned I don't have any relevant experience. But if you are running one train only why do you need DCC?

How do you propose to switch off the reversing modules for shuttle operation? And why?

Perhaps the first step should be to consider a connection diagram for the modules, power supplies and track connections. A few moments thought about this challenge and I quickly came to the same conclusion as Paddy, who when asked the way to the Post Office replied, 'To be sure, if I was going to the Post Office, I wouldn't start from here!'

Best of luck. You might need it!

Don

 

[beavercreek]

Hi Don
I think that in my earlier posts I did say that I would be using multi-pole switches (rotary ones..I have already got them in operation for other major switching duties) to switch between DC and DCC. These switches also will give the option of 'switching out' the reverse modules completely.
Why have DCC for one train...because I have some DCC-ed locos (with more being so) and would like to use them as well as having a choice from the non-DCC ones.
As has been stated already by 'Stainzmaster' if you operate an analogue loco on address zero, it will just oscillate back and forth inside the loop so there has to be 'real' DCC and also 'real' DC option.
Of course battery locos will just not need any of this malarkey,... but as I only have two at present I will press on with the 'dual' option system.

Thanks for the good luck though...I will have to be very very careful.....

 

[beavercreek]

Hi Roly
Did you manage to find your vid of the two reverse loops in operation?
I think that, like you, I will press on with just using the Massoth modules as they were intended and make sure that all wiring, and track issues, are sorted.
They should just work as directed...or else they are marketing something under false pretenses

 

[beavercreek]

Hi Paul

Nice plan
Yes I was told by Peter at Massoth that there might be issues when using 'short circuit mode' if there were two trains and one was in each loop.
I will only have one train and so, hopefully, that situation will not arise.
I was going to use the sensor set-up as they are necessary for DC operation. How have your loco wheels etc fared under the 'short circuit' operation?

This is my plan with the red amendments to make the reverse loops on the old 'shuttle' line

 

[beavercreek]

Hi Paul
Yes I was told by Peter at Massoth that there might be issues when using 'short circuit mode' if there were two trains and one was in each loop.
I will only have one train and so, hopefully, that situation will not arise.
I was going to use the sensor set-up as they are necessary for DC operation. How have your loco wheels etc fared under the 'short circuit' operation?

I haven't noticed any adverse effects on the chrome plating of the wheels on any loco Mike - no noticeable sparking when the leading pick up wheels make contact as they drive over the split section either. The two loops have been in operation for the best part of seven years.

Excellent news!! If my hopes for the complex DC/DCC operation of the reverse loops comes to nought, at least I can see from your experience that the simple.'shorting' will be fine.
I edited the last post and inserted my plan of the changes.

 

[beavercreek]

Just found the video of the double LGB reverse loops on my old railway. Its actually already on Youtube
http://youtu.be/5vjAbU_xfmc

Excellent Roly!
I take it that your layout was all DCC.
Do you still have a track plan for the old layout?
Did you use the LGB 10152 for the insulated gaps?
10152

 

[Cliff George]

Sorry Mike I'm having difficulty getting my head round this. Have you got a wiring diagram of how you intend to wire all of this up Mike? I'd recommend drawing it out first as don6GLC has already recommended. Post that diagram on here, I'm sure you would get many responses.

Because of the DC reverse loop operation, two modules are needed.

......

Peter at Massoth has said that you have to have two modules (one at each loop) if there will be any DC running.

I don't really want to argue with the great man (Peter that is!) but why do you need two reverse loop modules to run with DC? As don9GLC has already stated with DC you need to switch the polarity of the main line between the loops and not the loops themselves (think about what would happen if you switched the polarity of the loop while a DC train was in them loop - it would just reverse). I can't see how you could operate with more than one reverser while using DC.

It's not impossible to arrange to switch all the necessary connections but it does not seem to be simple. If you only operate one train at a time it might be possible to operate DCC with the DC wiring connections (switching the main line polarity) ......

Yes I agree. Only one reverse loop module would be required and the wiring would be much simpler.

In reality you would have to be very careful running more than one train at once in your dumbbell arrangement. You would never want to have trains going at the same time in opposite direction on the main line between the loops, although it might be fun to watch. You've already said you are going to have this restriction anyway:

The reverse loops are at either end of the single line so only one train will ever operate.....

and

I will only have one train ?...

Now I say all this....but as I am connecting up the loops as just plain DCC to begin with.......I may just stay with that and investigate using a Massoth 'feedback' unit to get a shuttle operational under DCC as well....

Bigjack is the man to talk to about that. I saw him set it up at an Essex indoor meet once.

The reversing loop modules do seem to "talk" to each other - on the rare occasion when there is a train passing through both loops at the same time, the auto cut out comes in and all trains stop.

Yes that is because in short circuit mode both units will switch whenever there is a short circuit. An advantage of using the sensor mode is that this problem is eliminated.

 

[beavercreek]

Hi Cliff ...well...
To answer some of your uneasiness with my intentions:
Not only from Peter at Massoth, but also I have been also informed by Mohammed (the American Massoth guy) that if I was going to be running two loops with DC, then two modules would be required. As the two guys work and support their own products and as I have two modules (very cheaply bought) I will go with their advice....it may be wrong advice but.......

Indeed I have said on more than one occasion that I will only be running ONE train between the loops as I think that I do realise that not only the two trains might trip the short circuit in both loops at the same time, I also realise that a head on collision is very very likely on the single connecting line! I maybe a person of small braint but I ain't a fool

Here is how my use of the DC/DCC operation is formulating in my little head with really only one real problem.......
The wiring for the switch from DC to DCC in the loops will be controlled by a multi-pole rotary switch.
When switching to DC:
This will reverse the inside/outside connections to theloop (also switching in the DC track power to come directly from the DC power supply instead of the track connection ) and also switch in the dedicated module power supply necessary when operating in DC mode. The sensors remain the same.
When switching to DCC
The track connections (inside and outside loop) will be 'swapped' back and the power supply (now to be DCC) will 'swap to the track connection outside the loop. The modules little 'dedicated' power supply will be switched out as well as it is not needed when in DCC.

The two connection diagrams (DC and DCC) in the PDF on the Massoth website show the necessary 'swap' that will for the DCC to DC operation.(and back of course)
The basic switching wiring will be interesting but not insurmountable.

To the problem.....
The really problematical bit for the wiring is the loop that is far away from the main track supplies. The track feed has to go to the module first when in DC mode. Feed cannot be taken from the track outside the loop as it can for DCC. Now the loop near to the place where all track power is fed is an easy hook-up but the one far away is another kettle of fish and will necessitate the running of the power supply cable all the way up to the far loop area.
If the two Massoth guys had said that one module was fine for DC then this problem would also melt away..but they didn't

Anyway...
As I said in a previous post, I will be trying the system only with DCC to start with then bring in the DC option

Of course the DC back and forth 'shuttle' will be very much like it is now and just operate happily as it is working between two sections that are near but outside the 'loop' electronics.