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16v DC bus

1937 Views 31 Replies 5 Participants Last post by  rosco01
Hi folk,
second post - this time concerning installation of a separate DC bus for power supply to Peco point motors and also Kaydee electric uncouplers.

I have watched a number of You Tube vids showing how folk have employed a separate power supply outside the usual ECoS booster available from the unit itself. It is my intention to do likewise, but I am unsure of what to purchase (Australia) and how to arrange componentry - I most certainly do not wish to compromise this very advanced and expensive control station...

The two main questions concern what to use as a power supply and how to provide a voltage controlled DC from it.

My current (excuse pun) intention is to purchase an 18v AC 2 or 3 amp "black box" supply (computer PS or similar) and to connect that to some form of voltage regulator/rectifier to provide a constant 16v DC output to the bus - which will run the length (shelf, end to end) of my layout.

I do not know if I need to fit anything at the end of this bus to complete a circuit, or if it simply can be two leads running in figure 8 pattern without termination. (I understand, whether there is need or not - that termination is always good practice).

I do not quite understand the limits of Switchpilot with regard my Peco solenoid point motors - however, I have read that I can change the CV's to provide a higher output from switch pilot... whether this will subject the unit to possible destruction using the Peco motors is another question for those who have experience/knowledge in such.

I have a number of original Shinohara points, including the double crossover... I would dearly love to include that into my layout - but understand there is considerable modification required to prevent shorts...
My intention is to use the "servo" connections of Switch Pilot and connect two pairs of servo's to each - operating in parallel.... I can purchase a "Y" cable (as used in r/c aircraft for coupled servo controlled surfaces) - and I will make the necessary linkages for each end of the double crossover work in unison.... also fitting a pair of micro-switches to supply power to the frogs and prevent shorting. These micro switches, I believe can be operated nc/no by an additional control wire from the servo horn...
complicated - yes, but I believe achievable. I have a number of years experience in r/c aircraft and in similar arrangements...
It would be far simpler to employ the switch pilot servo version and also extension for this, but also much more expensive in comparison to a simple Y lead and micro-switch/servo control rod.

That's probably more than I need to put to the forum for now.. I'm stuck with electric uncouplers for now, and can go no further with my layout... the questions above will divert my thoughts for the time being until clarification and advise from Kaydee is received on the uncouplers....

Much appreciated,
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I use ESU Switch Pilot servos for driving servos for changing points and semaphore signals. In the beginning I used the track power for both the signal and power supply but as I added more servos I reached the point where the switch on current required by all the servos starting up was too much for the ECoS and it went into a continuous reset mode.

I fixed the problem by providing a separate A/C supply from a transformer which was within the voltage range specified by ESU.

My Continental shelf layout is controlled by Roco kit. The Roco decoders also have a separate power input and for that I bought a DCC Concepts power supply which provided a voltage which met the Roco specification.

So long as the power supply you use does not exceed the rating for the accessory decoder you should be fine.

On the subject of using Y connections to drive two servos from one output, I haven't tried that.

It would be far simpler to employ the switch pilot servo version and also extension for this, but also much more expensive in comparison to a simple Y lead and micro-switch/servo control rod.
I'm not quite sure that I'm interpreting the above correctly. But, the Smartswitch can be used with both Y leads and operate several control rods, from each Servo. Using the spare Servo arms, which come with each Servo, it's simple to use a spare arm to:-

Reduce the Servo throw from 180deg at the Servo, to the 3mm throw for the points and another rod, lower down the same servo arm, to the Peco Dual micro-switch, for Frog polarity.

The second micro-switch can isolate a length of track leading to the heel of the associated points, for heel protection.

It also has outputs for signals, at the right voltage for direct connection to LED signals.

Thank you David, much appreciated. Yes, it is my intention to provide a separate designated power supply to the power input of Switch PIlot decoders, but of course - the track input/decoder signal must also be connected - not as supply, but for ECoS DCC control. Further, the decoder CPU input will be supplied from this separate 16v DC bus....for supply to the point motor solenoids, but I need to reduce voltage further to around 12v DC.... for decoder CPU voltage... there are three input/output pairs of terminals in Switch Pilot - track bus (for ECoS), decoder CPU supply and point motor supply. As I understand it, track bus and point motor supply can be bridged .. but I will not employ this... and connect an independent DC bus of around the 16v.
Although very in depth, the ESU manual has created confusion for me - of course, the manual has to provide for all practical applications, and lost me a few times within some of the varying options....

From what I have read - this is practical.... and will serve my layout well, regardless of how many switch decoders I add. Supply to point motors from a separate 16v bus may however exceed the overload protection of Switch Pilot, and I understand that CV's can be changed for this protection to be raised to a higher demand.... I do very much hope that this does not simply remove protection altogether - I doubt ESU would ever make this possible.

Another option which I am currently considering, which should fully protect any threat to Switch PIlot - is to include small relays at the points... a little cumbersome, but by fitting a small relay capable of the 16v DC at 2 or 3 A. for each solenoid, and connected directly to the 16V DC bus I propose - would result in only the current draw of these relays on the outputs of switch pilot.
We spend an enormous amount of money on ESU (and other brands) products, yet for some strange reason - seem to whince at the prospect of a very minute amount of cash for inclusion of componentry which will prolong the life of it.
I'm not sure my plan for incorporating these relays would prove effective, I don't yet know how Switch Pilot would work in conjunction with them being in series between switch pilot outputs and the point motors... but at present, can't understand why not....
Further, I suspect it possible (not mapped out yet) that each relay can also switch contact of the frog..... it's all a bit foggy at present, and I believe it won't be until I actually begin wiring up my layout, and finally power up ECoS and the associated ESU devices that I will begin to learn what will work, and what doesn't...

Again, David - thank you kindly for your reply - being new to DCC and drawn into it from the dark age technology of DC and its simplicity of just two wires.... I am very much on a vertical learning curve, and it is both comforting and reassuring to appreciate that there are folk at hand on this forum to assist and advise... thank you.

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Thank you, Julian - I read through your reply a number of times and now understand that I have created confusion in my original post...
Yes, it is my intention to make use of the two servo sockets of ESU Switch Pilot to control operation of the four sets of points in my Shinohara double crossover.
Of course, a "pair" of points must work together - and there are two such "pairs" in this crossover.
With the use of a servo "Y" lead, I can pair the two servo's together to control both sets of points using the one servo socket of Switch Pilot, and thus - the two sockets of the unit will in fact operate the four servo's needed for this cross-over..... hope that makes sense?

With regard to the servo arms - my intention is to create the rods to operate each set of points in this cross-over - to each needed length.....
I also believe i have option to employ a thin rod working on a fulcrum within the servo mount - which will provide tension against retaining the point blade in position... yet prevent any excessive load or failure to close the point gap at each end when just one output from Switch Piilot is utilised for two servo's....
I have seen this posted on line, in vid format - and quite like the concept of using tension within the rod itself to hold the point blades in contact with the stock rail.

As for frog power switching - my intention is not to incorporate any form of manufacturer componentry, but simply by adding one additional rod to one of the two servo's arms (only need one for each of the two paired sets of points) and this can be mechanically set to open and close a micro-switch.... allowing the nc/no contacts to throw power supply to the frog and eliminate shorting as metal (all my rolling stock have metal wheels) wheels cross the frog...

As for preventing issues with the heel supply, I have fitted insulated track joiners to all "frog" ends of my turnouts... supply to all sets of points comes in from the single "common" end (not sure what the correct term is)... from what i understand, this will prevent issues with supply to the points coming in from both ends of the points, creating potential shorting issues as the wheels leave one supply end and enter/connect the other.
All of my track sections beyond the frog end have their own jumper from a sub-bus... and, of course - the sub-bus is connected to the main DCC bus...

I'm totally new to DCC, and thank you very kindly for your reply, aplogies if I created confusion with my original post... and apologise for what my be even more so with the above.....

much appreciated,

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Thanks for the clarity on the use of the Switchpilot.

You may be interested in a couple of ideas for controlling the pressure along the rod to the switch-points. Both are simple and very cheap. The coil, compression, springs are just purchased online [a couple of dollars] and very cheap for packs of 20 / 40 / 100 etc. I got several lengths, so as to be able to experiment, the ones in the picture are 9mm long, but I have some at 3mm and also 4mm. [NB. They also come in OO wagon, 3-link, coupling packs, which gave me the idea in the first place, but prices caused me to look online, where there are simply loads available.]

These are over the board, for use under platforms, but operate equally well under the board.
Wood Line Font Electronic device Screenshot

The crossover, both from the one servo.
Circuit component Passive circuit component Hardware programmer Electrical wiring Audio equipment

Coil springs do the same job, but occupy much less space. The connectors are readily available in model a/c or boat shops. I left the pins on the alloy connectors, for illustration, they are now gone.
Wood Line Gas Composite material Electrical wiring

The pictures are from a mock-up trial, to see how practical it might be.
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The ESU Switch Pilot servo allows you to set the end points for the servo so you don't have to do anything special with the actuating arms. For one Switch Pilot servo driving two servos off the same drive you will of course have to ensure that the mechanical linkages match.

I mount my servos under the baseboard with the operating rod run along the rotor arm like this:
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Thank you Julian and David - this is exactly what I wanted to learn.. very much appreciated.
I have much to consider now, and plenty of options to install servo operated points that will not cause the servos to struggle with both load or specific end point adjustments in unison.

I have employed the coil spring arrangement on internal combustion (IC) model aircraft engine throttle control (cable) and it works very well. It would lend itself adequately with point blade control.
I had not considered the wire spring method (in fact, was not aware of it) - but with your pix, I now firmly believe it the most appropriate for controlling two sets of point blades from the one servo. Further, i believe adjustment to "centre" the positioning of both points in unison to be quite easy - simply adjustment by moving the common linkage rod at the servo arm connection ... infinitely variable using the screw as a clamp on the control rod - this has been a most wonderful suggestion, thank you Julian.

David, yes - fully appreciate that both sets of point blades must be set equally, not only in the set position - but also with equal fulcrums and travels etc, or we end up with a "ratio"...
I do like Julian's method of the control wire with control of end point under tension/compression from the wire spring arrangment near the point throw arm... I will conceal all of this beneath my base board. Use of two identical servo control arms remotley at right angles and adjacent to the points is a most suitable arrangement... and should be almost maintenance/trouble free.

I will also include a further control arm to mechanically operate a micro-switch - NC/NO for supplying power to the frog of each pair of points in the Shinohara double crossover.
I have yet to fully contemplate the modification of the earlier version I have (original).. expecting this to be a considerable project... but highly achiveable with my modeling skills from a life time in modeling.. with much scratch building in many facets of the hobbies associated.

Thank you both kindly for your suggestions - they have opened ideas which I had not considered.

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You might like to consider getting the switchpilot companion relay module. This will plug in to the switchpilot and provide relays that work in conjunction with the servos to switch the frog polarity, much easier than messing about with micro-switches.

Using a DC switchmode power supply will be ideal for powering the switchpilots. 16V DC will be fine to use directly, there is no need to regulate it further.
Thankyou Suzie - yes, it will save considerable effort to fit micro-relays and ECoS/Switchpilot will do all the work for me.
Comforted to learn that 16v Bus will work satisfactorily through input/output of Switchpilot for operating Peco point motors.
I have purchased a 19v 3.42A power supply (computer) - and an adjustable DC-DC steptdown regulator - I can set 16v DC bus as needed for both supply to Switchpilot points, and for Switchpilot ECU supply (both end of Switchpilot).

Thank you for your kind assistance, suggestion and re-assurance.

Good afternoon Everyone Interesting posts Rosco you might want to put some Bus Spike protection at the end of the Bus i attatch a pic from Dcc Concepts of the article.


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Thanks Babs,
I had not heard of these previously - no idea why they should be considered. My Bus is relatively short, length of the shelf layout along one wall of an unused bedroom is 3.5m....
I will be using ECoS and associated ESU componentry for the entire layout, including loco decoders.

The ECoS Bus will only be used for track. I am adding two additional Bus's, one at 16v DC and one at 12V DC.
The 12v Bus will supply power to the control input of SwitchPilot units.
The 16v Bus will supply power to relays at each set of points - controlled by Switch Pilot, and also to KayDee electric uncouplers.

The two "accessory" Bus's are supplied by a 19v 3.42A "computer" power supply - two adjustable DC-DC Buck units receive power from the P/S.. and control voltage output to my chosen 16v and 12v Bus's respecively.

I have broken up feed from ECoS to the track layout into many isolated "blocks" - not for signalling or running purposes at this stage, but to enable separation from the frog end of all sets of points....
I may consider the fitting of a 12v globe between the ECoS Bus and each sub-Bus...

Hope that explains how I intend to power the layout.

As for the inclusion of the suggested Bus Spike protection - I would appreciate a little more information, particularly in relation to the relatively small and "ended" arrangement of my shelf layout.

Thanks again, much appreciated...

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Just adding a little more to this thread - Shinohara double crossover.....
I have decided to purchase ESU "Servo" Switch Pilot and the "Extension".
This unit will enable me to fit 4 servo's to the crossover, if I have issues with the above suggested "joined" pushrod method to control 2 sets of points in unison. It is my intention to attempt this first, but if I am unsuccessful - I will opt to fit the additional 2 servos and have all four sets of points dedicated to a single servo each.... the "extension" will allow me to control power to the frogs... as I understand it.

With the remaining Peco Insulfrog points, my intention is to fit a standard automotive 12v relay to each coil of the point motor solenoids.... assuring me that the higher amperage demand of these point motors does not require me to alter CV settings in the Switch Pilot units and remove overload protection... I have purchased quite a number of these relays at a very low cost.... I searched for micro-relays which would afford a less cumbersome appearance and layout beneath the base board - but the price of such is far greater than the humble automotive variant...

The output from Switch Pilot units will only be drawn by the coils of these auto relays - power to the point motor solenoids comes from a dedicated 16v Bus.... hope that explains my intentions.

I have a separate 12v DC bus which will supply power to the input side of Switch Pilot.... which may be a little overkill - I intend to keep my supply and "track" as separate...
The 12v DC bus will also afford me option to add additional components at a later stage, and will not draw on the ECoS supply through the track.....

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I just noticed your mention of the one servo to control 2 x points at a time on the crossover, ie single control rod to two servos. I'm not sure if I mentioned any detail about the spare servo arms, used as ball cranks and throw reduction arms. The picture shows how I made sure that when one set of points is pulled, the other set is pushed. I simply made use of the small arm on opposite sides of the cranks.
Rectangle Slope Font Parallel Circle

For axles for the crank servo arms, most of the spare servo arms [around this size] have 3mm screw holes, there are a few with 2.5mm screw holes, but I have a 3mm drill bit and use the same bolts.

Some ideas and principles are pictured below, too.

Rectangle Slope Font Line Parallel

Obviously the PL-15 connector rods won't be needed, as you intend using Peco electronic frog polarity switching.
On the topic of the Smartfrog, I don't think that using one servo for two turnouts can done, if using the Peco Smartfrog, as each of the two frogs pairs will need opposite polarity.
It could, however, easily be done using Train Tech RL1 Relay controllers.
Relay Controller

Relay controls could be either from the same Smartswitch output ports, top of Page 3, or [easier] giving each RL1 the same DCC address as each Servo you are using, lower Page 3.

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Thank you Julian for your very detailed description and for the effort you have given my questions. I understand how you have employed a bell-crank to control opposing direction from the central drive of the servo.
I further understand how you have effected ratio throw to maximise servo arm travel and minimise point rod throw...
I will make excellent use of the information you have posted.
Further, I have read through your suggested links and have a better understanding of how relay control and block working can be effected.... these are now matters for consideration.
Sadly, I do not believe my ESU loco decoders have the "diode" braking system incorporated, but I may very well be incorrect in this... I have not sat down and learned the full potential of my decoders. Further, I have not fitted one into any of my loco's as yet....... nor have I connected up any of my ESU components nor turned them on.

I made the decision to stay within the ESU range for componentry - in the belief that it will all lend itself compatible and auto-detect in most cases...

For now, I am in the midst of laying track and working through installing point motors and wiring... My main DCC bus is fitted, along with leads to a sub-Bus and jumper further leads from soldered joints at the rail to each sub-Bus.... this is keeping me very busy at present, but - I am attempting as best I can to ensure my work does not require dismantling to effect what you have kindly posted....

I have had to pull up much of what I had previously laid - not being aware that track laying is not simply a "lay and fix" procedure, but is very much post providing for inclusion of point motors, linkages and electric uncouplers etc. etc.... one step back for each two steps forward, so to speak... but, it eventuates in that "one" step forward....

Much appreciated,

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Are you using Peco Points? Their additional holes at each end of the points Tie Bar are very useful when it comes to adding control rods [from any type of Points motor]. It's even possible to drill a small slot to the side of the Tie Bar, for access to the underside of the boards without having to lift Points already laid. Other makes can normally have a 1mm hole bored in their Tie Bar ends, too. [Possibly Granny, with an egg, stuff??]

By the way, I don't know about other folks, but I tend to lay the track, without any fixing, until everything is set up. I have sometimes popped the odd track pin through a sleeper, where I want to hold a particular bit of track, before permanently fixing it. [Normally to hold curves in place at track joins] I leave them a couple of mm proud, so they can still be pulled if a change is needed. [Possibly, more egg??]

Best wishes,
Thanks yet once again, Julian.
Yes, Peco Insulfrog points - n/s track joiner at the common end, insulated at both frog ends.
Power supplied from the common end track feed.

This is both the first "shelf" layout and also "HO" layout I have laid...
Previously (30 years back) I laid down a Peco streamline N scale layout on a standard internal house door....
I mapped out the layout using grey lead then began the process of folling my lines laying track down on cork underlay with track pins.... Peco insulfrog points were used with solenoid point motors. It was (of course) a DC track, I constructed both the CDU for the points and a "knock off" EDA control unit.
I created a track "mimic diagram" with push buttons arranged where points were located.. white and black buttons..... and to run Kato and Atlas loco's around the track with all the rolling stock I had to make up trains was quite easy... even for my kids...
It was simply a matter of following the mimic diagram painted on a ply plate.... and to press the points buttons for the intended route.....

When I came to this shelf layout - I had no idea what I wanted.. other than a main line to give opportunity for loco's that i have both scratch built and also constructed from brass/white metal kits... opportunity to at last get some decent length of track to run on... other than previously one length of flexi track...

I have amassed quite an amount of track (4 boxes of flexi track) and a large number of these insulfrog points...

Rectangle Packaging and labeling Font Carton Electric blue

I have no idea how many of these I will end up using... I am struggling to find use for the "curved" sets and believe they will stay in storage... or swapped out with someone who has straight sets who need curved.
I also have a number of Shinohara (original code 100) including this double crossover which I will add as a central focal point in the layout and a double slip - although I am struggling to believe I'll use that.
There are three sets of other S'hara points - one long curved, and two straight....

I have intention of creating a small shunting yard "ladder" with a run-around track....
Also, at the southern end from a platform track - a pair of servicing roads.. one for steam and one diesel.
I have two sets of Y turnouts for those...

Most of this is still in my head, Julian - I have laid down three parallel lines with points at both ends...
The "northern" end teminates behind the entry door to the room... the shelf has been tapered to the width of the narrow end space behind the door... and closing of the door has been limited to allow the width of a locomotive/wagon/carriage to be able to run up to some buffers..... this part of it has all be done...

I'm working from that end back.... placing points loosely down and adding more rail...
I had laid down all three parallel lines with track pins - then pulled it all up again when I was persuaded to do so using flexible gap filler instead of track pins.. which I was in the process of almost completing... when it came to realisation that it had to come up yet again to create holes for the point motors and electric uncouplers....

So, I believe you can appreciate Julian - I am hesitant now to lay any more down - for fear of it yet once again having to come up...

As such, I have now focussed my labour on modifying the double crossover for DCC... and contemplating wiring of the layout...

My main track bus is laid... which I have posted on in a previous reply.

I am about to lay both a 16v DC and also 12v DC bus.... but await arrival of some connection blocks purchased on line....

A number of other components have arrived.. those being adjustable timer relays for uncouplers and DC-DC buck regulators.... along with a 19v 3.42A power supply....

I have also amassed a considerable number of ESU components... ECoS, LokProgrammer, LokTester, SwitchPilot (3), Servo and Extension...

Then we come to the loco decoders.... I have three LokPilot for some scratch built loco's, and three LokSound decoders for an equal number of brass/white metal kit loco's constructed 40 years back...
I have a number of brass/white metal diesel loco kits to construct.... and also one large brass/white metal steam loco kit.... all amassed many years back. I have another brass/white metal steam loco kit on order, but it is not yet in production.. I expect this kit to arrive 3 months hence....

Always a modeller, since a very early childhood - but, my field is spread across many differing subjects... from r/c and control line aircraft, through slot cars and model railways.... throw into the mix my passion for three classic motor cars, fireman on a steam railway, fly fishing, a power boat and caravan (which takes care of three or four months of winter each year)... and my retirement is simply melting away in front of me... now some 12 years...

I feel as if I've thrown myself into the deep end with this shelf layout - so much to do, and no logical pathway through it for precedence...

I believe once I have my track plan worked out... I can proceed, and my questions all relate to encouraging reply as to method - in particular what takes precedence in some logical pathway.....

Thank you very much again for your very much appreciated reply, Julian... it is comforting to understand that I have such good folk who are willing to offer suggestion and advice....

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Retirement - a time when you can really concentrate on getting properly busy..... :giggle:

I don't know how I ever managed to get to work, Julian.... 12 years, at times seems like 12 months.

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Bump..... ok, I've run into trouble - didn't take long.
I have tried and tried to read through both ECoS manual and Switch Pilot Servo and have come to a brick wall attempting to get both to work in unison.
I'll try to explain what I have attempted, then post what the outcomes have been thus far.
I don't know if any forum member here has had success with using Switch Pilot Servo (8 outputs) and ECoS 2?

I am attempting to connect up four servo's to a modified Shinohara double cross-over - the frogs have been electrically isolated and jumper leads fitted to enable supply power from Switch Pilot Extension piggy backed to Switch Pilot Servo....

At first, I attempted to program the decoder using Lokprogrammer and my PC laptop - I could not get Lokprogrammer to read the decoder.

Next, I went to set up servo control via the switch pilot servo buttons themselves... and was able to eventually set end points and travel speed for the first four servo's...
I am using track bus power of some 16.5v - with jumpers between the track and power terminals.

Adding an additional two servo's for sets of points beyond the double crossover was also done satisfactorily..
I have (and continue to have) all six servo's working perfectly from the decoder itself....

Following the instructions - I managed to get servo #1 added into ECoS and added a single left point icon to the layout page.... the servo worked perfectly from ECoS.
It took me a while, but I learned that programming with ECoS demanded the address to be changed to 1,2 so that I could get the second servo working..
Following that, the next servo worked with 1,3 and the fourth 1,4.....
Having got that far, I was shocked to find that servo #1 no longer responded.. I had changed nothing as the other three were added.... yet, it continued to work from the decoder itself..... I am finding this very frustrating.
I deleted the first servo from ECoS and re-entered it... still not working, but ok from decoder..... ECoS will now not operate this servo.. and I don't know why.

I added another servo to ECoS at address 2,1 and it refused to operate.... yet ok at the decoder.

I added the sixth servo to ECoS at address 2,2 and it works perfectly....

I simply don't get what I am either doing wrong, or not doing....

I hope someone can explain and advise what is going on between ECoS and Switch Pilot Servo.. I will not add Extension to Switch Pilot Servo until I have all four sets of points of the double crossover working as they should.... three of the four are fine, but the first one does not now function from ECoS.. yet it does from Switch Pilot Servo?.... smoke and mirrors to me...

Can someone kindly enlighten me if I need to somehow get ECoS to "learn" Switch Pilot Servo... to me, there is something in there that simply isn't set up correctly.... Switch Pilot Servo and the servo's all working fine - but not from ECoS..... two of the servo's at #1 and #5 do not respond to changing point direction at all......

Any help/suggestions greatly appreciated...

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