Threeway turnout wiring using MTB MP1 motors

[ITG]

Hi 

I've reached the stage  now where i'm wiring a Peco threeway electrofrog symetrical turnout, using MTB MP1 motors driven by Yamorc YD8116.

The attached photo shows where the 3way sits, relative to other turnouts.

I think I'm correct in saying that each of the RH & LH turnouts at the bottom cannot share a DCC address with one of the motors on the 3 way? Please tell me if this assumption is incorrect, and how to configure if so.

But, if all turnouts need different addresses, and focusing on the 3way itself, how do I configure/wire the MTBs so they cannot foul each other by opening/closing in the incorrect sequence?

I will eventually be using Z21/iTrain, so I guess a possible solution is to create a route, but how else might i do this?

PS, I may of course also need help with frog wiring.

Thanks for your help

Ian

[WIMorrison]

You could get away with sharing two addresses if you simply made it two distinct crossovers, rather than two crossovers complicated by a three way turnout.

 

that would spoil the symmetry but be much easier to manage and wire.

[Michael Hodgson]

What you have is two crossovers (from the left line to the middle line, and from the right to the middle), but they conflict with each other.

With either a symetrical or an asymetrical 3-way, you don't want to group the points only with the corresponding motor on the slip - you need both sets of blades to the left or to the right to agree with the crossover that you're setting and those blades need to be changed in the correct sequence because the blades foul each other.

 

For the straight route it's one tie bar to the right and the other to the left, but transposing those tie bar positions is impossible, again because the blades foul each other.

[ITG]

Thanks Iain,

I see that, but sticking with the three way, would I be correct in thinking that iTrain may help with route setting to ensure blades move in the correct order?

Or is there a wiring trick with MTBs?

ian

[ITG]

4 minutes ago, Michael Hodgson said:

What you have is two crossovers (from the left line to the middle line, and from the right to the middle), but they conflict with each other.

With either a symetrical or an asymetrical 3-way, you don't want to group the points only with the corresponding motor on the slip - you need both sets of blades to the left or to the right to agree with the crossover that you're setting and those blades need to be changed in the correct sequence because the blades foul each other.

 

For the straight route it's one tie bar to the right and the other to the left, but transposing those tie bar positions is impossible, again because the blades foul each other.

Yup, found that by trial and error, but how do I overcome the conundrum?

ian

[WIMorrison]

ITrain will set the routes correctly through the turnouts without issue, however it won’t to the wiring for you 😀

[5BarVT]

12 minutes ago, ITG said:

Or is there a wiring trick with MTBs?

You can use extra switches on point motors to stop the opposite one moving when it shouldn’t.  But the MP1 only has one switch which is needed for frog switching.

I would expect iTrain to be able to manage the conflict once you have got that far.

Until then, you just have to instill good practice and always set the other crossover straight before setting one to crossing.

You can still share the same dcc address for each of the three way points and the appropriate other point - it doesn’t help with the three way conflict, but it doesn’t make it any worse.

Paul.

[WIMorrison]

The MP10/MP5/MP6/MP4 all have two microswiches making them an ideal way to solve the issues presented by this design. 
 

There will also be another version soon that will have a decoder built in that will also have two microswitches 😀

[ColinK]

I’ve just been researching almost the same problem, but for points that are DC controlled using stud and probe control.

 

There is info on solving this for DCC on the DCC Concepts website.  Also have a look at Brian Lambert’s website as there are solutions for this on there too (I only looked at the DC solutions).

[WIMorrison]

There is no difference between DCC switching or DC switching, plus the wiring is the same.

 

You get exactly the same short circuit if wired incorrectly with both DC and DCC

[ITG]

1 hour ago, WIMorrison said:

The MP10/MP5/MP6/MP4 all have two microswiches making them an ideal way to solve the issues presented by this design. 
 

There will also be another version soon that will have a decoder built in that will also have two microswitches 😀

I’m happy to invest in the necessary kit - given the two other crossover turnouts and the two motors required for the 3-way, how many, and which,  which would need to have the two microswitches, in order to facilitate correct throws without fouling?

And do you know of a wiring diagram suitable for this particular scenario?

thanks

Ian

[ISW]

4 hours ago, ITG said:

I think I'm correct in saying that each of the RH & LH turnouts at the bottom cannot share a DCC address with one of the motors on the 3 way? Please tell me if this assumption is incorrect, and how to configure if so.

But, if all turnouts need different addresses, and focusing on the 3way itself, how do I configure/wire the MTBs so they cannot foul each other by opening/closing in the incorrect sequence?

Ian,

 

You might be 'overthinking' this one? Although I do appreciate that you want to make it as automatic and foolproof as possible.

 

In my 'simplistic' world, it was just a case of correctly 'representing' the track arrangement on the mimic panel. 

 

Here is one of my 3-way turnouts, also confabulated (?) with one of the adjacent turnouts to form a crossover:

 

What I did was to simply show the 3-way on the mimic panel as a pair of turnouts in 'series' (the bit you want is blue in the lower-right):

 

To ensure the route(s) through the 3-way turnout are correctly 'configured' I therefore simply have to check that the two push-buttons (the turnout and the crossover) are correctly set. The only important part is to design the mimic with the 2 turnouts, representing the 3-way, in the right order! In both of mine (Peco Code-100 SL-E99) the RH comes 'before' the LH.

 

Hope this helps.

 

Ian

[WIMorrison]

@ISW The 'mimic' will created in iTrain and look similar to this 😊

 

[ITG]

Thanks all.

But having slept on it - or not, as I lay awake pondering it - I think I shall take @WIMorrison advice in his first response, to use two separate crossovers with respectively right and left hand turnouts. I have the space to do so, and it does simplify matters with both wiring and shared addresses. I simply wasn’t confident that I could achieve the operation I was hoping for, because of the risk of the three way failing to operate because of incorrect sequencing of the blades movement, and/or (if addresses were shared with the other turnouts), the fact that to get the three way in the right position, another turnout may have to switch, when I didn’t want it to. One less conundrum to frazzle my brain!
I can use the three way turnout elsewhere, where it is not linked to two crossovers.

Ian

[ISW]

7 hours ago, ITG said:

I think I shall take @WIMorrison advice in his first response, to use two separate crossovers with respectively right and left hand turnouts. I have the space to do so, and it does simplify matters with both wiring and shared addresses.

Now that's 'simplification' ...

 

Ian