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Petermac
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I'm running DCC, all Peco Electrofrog points.

I have a new section of baseboards carrying my storage roads - 2 in each direction (up line and down line) with crossovers mid way thus allowing either 2 short trains or 1 long to be stored on each road. The 3rd track on each side is the through route.  i.e. I have 6 tracks in total - 3 "up" and 3 "down".

As the whole of this area will be covered by a high level board, I want to build a mimic panel using LED's to show which route is set.

Ideally, I'd like to use my Lenz LS150's to control the Tortoise point motors.  Tabs 1; 2; 3; 4 and 8 will be used for the motor and frog polarity.  This leaves the other internal switch (tabs 5; 6 and 7) for the LED route indicators.

I've watched videos etc. of Tortoise/LED route indication until I look like a tortoise but they all seem to use DPDT switches and bi-colour LED's.

Is it not possible to use this spare internal switch to power the LED's directly - i.e. without the DPDT switch and furthermore, could I light up just 1 green LED showing which route is set ?  By that, I mean both the through track and the turn has a single green LED on the panel and, depending on which way the Tortoise is set, one or the other lights up ?  It's obvious to me that, if the "open" route is showing green, the other would be unavailable (red) without actually having to signal it as thus.

It could be that, as with the frog tab "4", only tab "7" is available for output, in which case, only one green LED could be wired.  Bi-colour ones, used in pairs, would presumably show either red or green depending on which way the current ran through them .................. :hmm

A final question - for now anyway - I've read that, if powered through the Tortoise switch, the LED's don't need a resistor because the Tortoise already acts as one.  Is this true ?

Sorry it's so long winded but I'm not at home and am slightly bored not being able to get at the actual layout ...........

Sol
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Petermac wrote:

Ideally, I'd like to use my Lenz LS150's to control the Tortoise point motors.  Tabs 1; 2; 3; 4 and 8 will be used for the motor and frog polarity.  This leaves the other internal switch (tabs 5; 6 and 7) for the LED route indicators.  Yep, go for that - both internal switches are SPDT completely separate from each other

I've watched videos etc. of Tortoise/LED route indication until I look like a tortoise but they all seem to use DPDT switches and bi-colour LED's. Bi-colour LEDs can be either 3 legged switched via SPDT  or 2 legs switched via DPDT

Is it not possible to use this spare internal switch to power the LED's directly - i.e. without the DPDT switch and furthermore, could I light up just 1 green LED showing which route is set ?  By that, I mean both the through track and the turn has a single green LED on the panel and, depending on which way the Tortoise is set, one or the other lights up ?  It's obvious to me that, if the "open" route is showing green, the other would be unavailable (red) without actually having to signal it as thus.  Yep

It could be that, as with the frog tab "4", only tab "7" is available for output, in which case, only one green LED could be wired.  Bi-colour ones, used in pairs, would presumably show either red or green depending on which way the current ran through them .................. :hmm

A final question - for now anyway - I've read that, if powered through the Tortoise switch, the LED's don't need a resistor because the Tortoise already acts as one.  Is this true ?  Yep  as per instructions that come with the Tortoise



Now I am away soon for the day but later i will do some drawings and post them here but this site has lotsa info
https://brian-lambert.co.uk/Electrical_Page_3.html

Sol
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And a few links etc in the YMR index

Sol
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Some simple drawings. The 3 leg Bi-colour voltage  -  & + depends on the type of common leg ,  anode or cathode

the scribble on the LHS toggle is DPDT

Petermac
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Many thanks indeed Sol - being our electronics wizard, I knew you'd come up with the goodies !!

I'll check out the index and also have a good read of Brian Lambert - if only to see how quickly I get lost ............... :roll: :roll:

Sol
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And for some - this may help re LEDs

https://www.dccconcepts.com/manual/leds-and-how-to-get-the-best-from-them/

Petermac
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Along with Doug, Worzels got 'is confused head on ...........................

I'm in the process of fitting Tortoise motors to my fiddle/storage yard.

This section will be controlled by DPDT switches incorporating LED route indicators on a mimic panel.

The Tortoi have 8 outputs.

1 & 8 will be connected to a dedicated 12v transformer,  2 & 3 are connected to the track and 4 to the frog.

This leaves 5, 6 & 7 for the LED indicators.  I'm guessing No 5 is connected to the LED but where do the remaining  contacts go and where do they get their power from -  do I need another transformer or are they already powered internally by the Tortoise ?

Sol
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Petermac wrote: Along with Doug, Worzels got 'is confused head on ...........................

I'm in the process of fitting Tortoise motors to my fiddle/storage yard.

This section will be controlled by DPDT switches incorporating LED route indicators on a mimic panel.

The Tortoi have 8 outputs.

1 & 8 will be connected to a dedicated 12v transformer,  2 & 3 are connected to the track and 4 to the frog.

This leaves 5, 6 & 7 for the LED indicators.  I'm guessing No 5 is connected to the LED but where do the remaining  contacts go and where do they get their power from -  do I need another transformer or are they already powered internally by the Tortoise ?   NO , they are completely separate from the operating circuitry of the unit


Peter, I will do a drawing tomorrow.

but have a look at these first
https://www.bing.com/th?id=OIP.NFQTgxZ-hMx6JchTAMlwJwHaEW&pid=Api&rs=1

https://www.trainboard.com/railimages/data/1420/Tortoise_LSNC_rear.jpg


Petermac
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Thanks Sol - it seems I'll need 2 transformers in that case - 1 to power the motors and another for the LED circuit .............................

Maybe using the LS150's offers some advantage beyond just controlling the points afterall.

Sol
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Petermac wrote: Thanks Sol - it seems I'll need 2 transformers in that case - 1 to power the motors and another for the LED circuit .............................

Maybe using the LS150's offers some advantage beyond just controlling the points afterall.



No - one 9 or 12 v DC output will do both - drawing will come in about one hour after I have had breakfast.

Sol
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Peter, this is just of many ways of having LEDs for route indication using the same power supply as the operating circuit.


Fig 4 of the Tortoise info attached is the easiest I think.

Attachment: man-tortoise.pdf (Downloaded 5 times)

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Sol wrote: Peter, this is just of many ways of having LEDs for route indication using the same power supply as the operating circuit.


Fig 4 of the Tortoise info attached is the easiest I think.


Thanks for this Sol.

I'm still slightly (??) in the dark !!

Given that the Tortoise is able to power LED's without the need for a resistor, why have you put one in the +ve wire feeding terminal 5 ?

Also, from your drawing, it looks as if you've shown 2 LEDs - a red and a green (?).  I only want to use a single green showing which route is "open".  Would I wire 2 x greens (1 on each route) with the short leg on one soldered to the short leg on the other ?

Furthermore, would I connect the -ve from the LEDs to the -ve on the DPDT switch ?



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I think it is because the internal DPST does not have the stalled motor taking up current.  Powered directly by the DC current it needs resistors unless you want fried LEDs. Diagram 4 shows the LEDs as part of the motor circuit. Ron's method means no dimming when the motor is running. Much less confusing.

Nigel

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Thanks Nigel - I think I understand although doesn't the internal switch in the Tortoise do the same job ...............the LED's are after the Tortoise ................ :roll:

Sol
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Peter, the internal switches are NOT connected to the Tortoise operate leads 1 & 8 normally unless you do so.

Yes, both -ve's are the same - I drew it that way assuming it was self evident it meant the same power source - saves drawing another long connection.

The resistor is needed for the LED's in this case but not when used as per Fig 4 of the Tortoise instruction - those are in series with the Tortoise motor which acts as the resistor in that case.

Use what ever colour LEDs that you want - each one represents one leg of the turnout . Yes the short leg connections are to the -ve supply.

The LED circuit I provided is not connected to the Tortoise operate circuit in any way except for the common power supply.

Sol
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In fact I could have drawn it this way

It may show two supplies ( either 9 or 12 v - 9 volt makes Tortoise quieter ) but that is then upto the user.
this old circuit from one such relay set in old telephone exchanges shows many supplies but in fact is just one supply for the entire exchange


for explanation of the symbols for power.
https://electronicsclub.info/circuitsymbols.htm
https://electronicsclub.info/circuitdiagrams.htm


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Hi Peter,

Wot 'e sed. Contacts for the 2 internal; switches are independent of the motor supply, so you could rig a signal to one set and the frog to the other set, or in this case as Ron did one to the frog (using track power) and the other making a circuit for the LEDs (using a separate DC circuit). If you have a lot of LEDs you may need a bigger power source.

All depends on how many you want to run. Keeping the wiring and power supplies separate is actually not a bad idea.

Nigel

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Firstly, a Happy New Year to you Sol and Nigel - in fact, to all who read this !!

Thanks for the clarification about the resistor Sol - I think I'll leave you to digest the details of the telephone exchange - an on/off switch challenges me ...............!!!

When I mentioned the LED short legs, I think I read somewhere that if you daisy-chain a pair of LEDs -  long leg - short leg - short leg - long leg, when you feed power in one direction, one will light whilst the other doesn't and fed in the other direction, the other LED lights whilst the first will be off.  Not sure I've explained that very well but I know what I mean ......................... :lol: :lol:

Sol
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Peter, daisy chaining as you describe will mean no LEDs will light but if you parallel them in reverse - a short leg of #one LED connected to long leg of Led #2 and short leg of #2 connected to long leg of #1, then one or the other LED will light depending on voltage polarity - the same principle as shown in Fig 4 of the Tortoise sheet.

Petermac
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Further thinking on this subject ...............................

Switches:

Do I need to use DPDT switches or would SPST do the same job ?

On - On are what I need I think - i.e. no centre "off" position.

Where would one buy these switches (European readers only ......) ?  I have a few of each (DP and SP) in stock but, when I looked at current prices, I gulped !!!

I'm still not comitted to this system of control and do have my LS150's in reserve ...........................cost-wise, that might be the better way to go.  Presumably I could still have route indication although,  as I said at the start, physically having to throw a switch would avoid possible memory failures via an accessory decoder ........................... :hmm


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The type of switches DPDT or SPDT depends on power supply, refer to the Tortoise instruction sheet. Normally no centre off.

Outside of E-bay for switches, could try AliExpress & search for Toggle switches

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Thanks Sol.

I thought I'd replied earlier but the battery on my laptop went flat - obviously before I sent it !!

I'll have another read of the Tortoise instructions to see what the power supply has to do with the type of switch ..................but don't hold your breath about my understanding it !! :???: :???:

I did look at e-bay for switches and yes, they're much more reasonable than my previous supplier.

I'm now deep in thought about the design of the mimic panel - or more importantly, wiring it ................ :hmm

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Just re-read the Tortoise instructions and yes, I see where the DPDT and SPST switches differ in their installation.

I think in this instance, I'll use DPDT switches - I don't really want a "point bus" around the layout because, other than this section, all other points will be controlled by the LS 150 decoders.

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I'm planning to use the above diagram for my wiring Sol.

Can I just confirm that telephone cable (I think 4 twisted pairs) is sufficient to power everything.  There appears to be 5 wires going from the panel to each motor so using telephone cable would be ideal.

On the other hand, would I be better using heavier wire from the DPDT switch to contacts 1 and 8 on the Tortoise and just use 3 of the telephone wires for the LEDs ?  I do also have some 4 way alarm cable if that were the case.

Sol
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Peter, telephone cable is perfect.

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That's brilliant - many thanks Sol. :thumbs

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Just to throw a spanner in the works. All of my tortoi are fed from two transformers (bi polar) via single pole change over switches. The led route indicators are fed via the motor, so no resistors. The frog switches are fed straight from the track supply bus. I have to admit to losing it part way through the thread (concentration problems, long story) but hope this helps.

Sol
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Pete, just like Fig 2 of the Tortoise info sheet. That works well as well.

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Yes Sol,
I prefer to run the single bus around the layout and then the two wires to operate from single pole change over switches. With a lot of help from members on MRF I use twin wafer rotary switches for single and double slips. The second wafer operates the leds, and for these I have to use a separate supply with resistors.

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My situation is slightly different Pete.

I'm rebuilding a section of an existing layout and only this section will be operated via a panel and swithes.  The rest of the points on the layout will be DCC operated via an accessory decoder.

I specifically didn't want a dedicated "point" bus and also opted for the DPDT switches with a single power supply.

You say you got lost half way through the thread - that's half a thread better than me !!  I'm constantly lost ....................

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Petermac wrote: My situation is slightly different Pete.

I'm rebuilding a section of an existing layout and only this section will be operated via a panel and swithes.  The rest of the points on the layout will be DCC operated via an accessory decoder.

I specifically didn't want a dedicated "point" bus and also opted for the DPDT switches with a single power supply.

You say you got lost half way through the thread - that's half a thread better than me !!  I'm constantly lost ....................
:lol: :lol:


                 

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