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Tortoise switch machine power supply

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Tortoise switch machine power supply
Posted by Mullet19 on Monday, May 08, 2017 12:44 AM

Hi

i have a question for the experts here. I am confused on powerI got my switch machines. I have a 12v 1 amp power supply that plugs into the wall and the other end is a barrel plug. What am I plugging that into that will feed my bus lines for switch machines??

 

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Posted by gmpullman on Monday, May 08, 2017 5:16 AM

You Could plug your barrel plug into one of these and distribute the power to your turnout controls from it...

http://www.modeltrainstuff.com/Miller-Engineering-Power-Distribution-Board-p/mil-4805.htm

Sure, it's made for Miller signs but you can use it for any DC load.

OR you could just snip the barrel plug off and wire the power supply to your own terminal strip of choice.

I have found that the plus wire is "usually" the one marked with the white tracer but you can test that with a DC meter. With a Tortoise it really doesn't matter, if it doesn't go the direction you planned just switch terminals 1 and 8 on the machine.

Good Luck,

Ed

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Posted by richhotrain on Monday, May 08, 2017 5:29 AM

As Ed said, you could cut off the barrel plug and connect the two wires from the wall wart to the switch machine bus wires.

Is your wall wart AC or DC, and is it regulated or non-regulated? These issues matter as well.

Rich

Alton Junction

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Posted by peahrens on Monday, May 08, 2017 7:59 AM

I stripped the wire after snipping off the plug.  Ran one wire thru a fuse holder with a 3/4 A fast blow fuse. Then to terminal block for connectong downstream wiring.  In my case to barrier strips in my control panel then to DPDTs for Torti.

Paul

Modeling HO with a transition era UP bent

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Posted by MisterBeasley on Monday, May 08, 2017 9:23 AM

I use a 9 volt wall wart.  The lower voltage causes the points to move more slowly and I like that more than a faster throw.

It takes an iron man to play with a toy iron horse. 

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Posted by Mullet19 on Tuesday, May 09, 2017 12:18 AM

Thanks for all the responses. I have a much clearer idea what to do now. 

one of the questions was about power supply. It outputs 12v of filtered dc 

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Posted by richhotrain on Tuesday, May 09, 2017 5:46 AM

Mullet19

one of the questions was about power supply. It outputs 12v of filtered dc 

That is good. A regulated 12 volt DC power supply is just what you need to accomplish your objective. 
 
Now, just cut off the barrel plug and connect the two wire from the power supply to the bus wires.
 
Rich

Alton Junction

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Posted by GrandTrunk-HO on Thursday, May 11, 2017 2:25 PM

Tortoise switch machine power supply

Mullet19

I have a 12v 1 amp power supply that plugs into the wall

It outputs 12v of filtered dc

MisterBeasley

I use a 9 volt wall wart

The lower voltage causes the points to move more slowly and I like that more than a faster throw

richhotrain

That is good

A regulated 12 volt DC power supply is just what you need to accomplish your objective

Sorry to inform all of you, but only very old "Linear" V-DC power supplies were regulated. (now obsolete).

All present day power supplies and wall adapters are now only "Switching" V-DC power supplies.

The Tortoise switch machine is a (3) pole V-DC stall motor and is always drawing a constant power supply (current).

All Tortoise switch machines are connected in parallel to a V-AC or V-DC power supply.

As previously stated, you can use a (Miller Engineering 4805 Power Distribution Board) to connect (2) wires to each individual DPDT switch, that then goes to each individual Tortoise switch machine.

DPDT switch's are usually grouped together on a front panel on a small or medium home model train layout. There is absolutely nothing wrong with this procedure, but it requires much longer and a bundle of small connecting wires.

I am presently rewiring my old (2002) DCC HO scale model train layout to (2017) DCC. I have (27) DPDT switch's to control my (27) Tortoise switch machine's. I will be mounting (2) buss wires (+) and (-). Using #14 (1/16") Dia. solid copper wire with the wire insulation removed.   

As previously stated, the Tortoise switch machine operating at 12.V-DC, will have the Tie Bar, moving the (2) switch track rail contacts much faster.

Using a 9.V-DC will have the moving (2) switch track rail contacts move much slower, more prototype (realistic). 

I will be reducing the 12.V-DC power supply to each of my Tortoise switch machine's, down to around 9.V-DC. The internal (9) gear drive connections make a lot of gear noise at 12.V-DC. 

Add a variable resistor (Potentiometer) to reduce the 12.V-DC power supply down to around a 9.V-DC. 

Caution;

As the V-DC power supply is reduced, so will be the constant V-DC power supply to each Tortoise switch machine, in stall mode, to supply a constant pressure on the (2) switch track contacts.

Tortoise Switch Machine

Lowest = 4 ma. during operation.

Lowest = 15—16 ma. at stall, for each individual switch machine (always on).

Calculations;

Power supply; 12.V-DC

Power Supply; 1.Amp

 

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Posted by richg1998 on Thursday, May 11, 2017 3:44 PM

I prefer 9 vdc also.

I used an LM317 voltage regulator, couple resistors and a couple caps, plus a heat sink for the regulator. Just a small piece of aluminum. I used the LM317 that has a tab for heat sinking.

Specs can found online with a voltage calculator and diagram.

I did the same for the signal system which uses TTL chips at 5vdc.

Rich

N

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Posted by peahrens on Thursday, May 11, 2017 4:26 PM

GrandTrunk-HO
Sorry to inform all of you, but only very old "Linear" V-DC power supplies were regulated. (now obsolete). All present day power supplies and wall adapters are now only "Switching" V-DC power supplies.

Can you clarify about regulated power supplies?  Are they now unavailable, less avaliable, being phase out for some reason.  I have bought a number (two last week) of these Miniatronics regulated supplies for my building and signal lighting circuits.  It says it is regulated, which I understand to mean it should provide close to the target 12v DC at various loads up to the rated 1A.   

http://www.hobbylinc.com/miniatronics-plug-in-wall-transformer,-regulated-12v-dc-1amp-model-railroad-electrical-wt12

On my Tortoises, I used the Circuitron supply available in 2012.  I don't recall whether is was stated to be regulated, or just filtered (not the same thing).  For my Tortoises I happened to include a bipolar LED indicator at my DPDT in line with the power to each Tortoise.  The LED drop of 2v or so means the Tortoises see about 10v, with the Circuitron supply powering 21 Tortii.

Paul

Modeling HO with a transition era UP bent

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Posted by MisterBeasley on Thursday, May 11, 2017 5:00 PM

I like to add a fuse into my various layout power supply circuits.  Once the system is wired and running properly, it's not likely to ever need a fuse, but it might save you a power supply if you make a mistake while wiring or you cross terminals with a screwdriver while working under you layout on something else.

It takes an iron man to play with a toy iron horse. 

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Posted by GrandTrunk-HO on Friday, May 12, 2017 8:26 AM

Switching Power Supply

These types of power supplies are much cheaper to manufacture, much smaller and release much less transformer heat.

peahrens

Can you clarify about regulated power supplies?  Are they now unavailable, less available, being phase out for some reason.  

I have bought a number (two last week) of these Miniatronics regulated supplies for my building and signal lighting circuits.  

It says it is regulated, which I understand to mean it should provide close to the target 12v DC at various loads up to the rated 1A.   

Sorry, I stand corrected. I did not realize that you can still purchase a wall AC/DC wall adaptor that is a switching power supply that is Regulated.

A voltage regulator is a device that controls or maintains a constant voltage output of a power supply. Some (more expensive) V-DC power adapters have voltage regulators built in, while most do not.

Miniatronics is selling (4) different plug-in wall AC/DC adaptors. Only model # WT12 is regulated and costs almost twice as much compared to the other (3) AC/DC adaptors.

This UL approved transformer is perfect for those times you must have 12 volts DC and can not exceed those specifications. Using this transformer will assure you that all of your 12 volt accessories will always function as they were designed for. 12 volt bulbs will last much longer using a regulated transformer thus avoiding a failure due to higher voltage surging through your bulbs.

Digitrax PS2012

A 12 to 23 V-DC 20.Amp (Regulated) switching power supply.

Digitrax PS514

A 12 to 24 V-DC 70.W (Not Regulated) switching power supply.

  

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Posted by GrandTrunk-HO on Friday, May 12, 2017 8:34 AM

Tortoise Switch Machine Power Supply

richg1998

I prefer 9 vdc also.

I used an LM317 voltage regulator, couple resistors and a couple caps, plus a heat sink for the regulator. Just a small piece of aluminum. I used the LM317 that has a tab for heat sinking.

Great idea about bringing up the LM317 voltage regulator. I totally forgot about going this electrical procedure.

I actually use many different types of step down Boosters, using a voltage regulator to control low V-DC voltages. There is no need to build a custom voltage regulator. Ebay sells many dozens of different types of Boosters.

This looks perfect to supply V-DC power to all Tortoise switch machines. There are Ebay listings for around $5.00 and it comes in a blue or a green colored circuit board.

LM2596 based 1.25V-DC --> 37.V-DC (3.Amp), fully adjustable Buck voltage regulator with a LED display. (voltage input -OR- voltage output).

Features of LM2596 Adjustable Buck Voltage Regulator

Voltmeter error is ±0.1V in the range of 0~40V. (Please make sure that the input voltage is 4V or more).

Press the micro switch to measuring input / output voltage. LED light indicator will show, which voltage is currently displaying.

Power off memory function show that circuit voltage values measured for the last time before switched off.

Wide Input voltage range:4V~40V (Input voltage must be higher than to the output voltage of more than 1V).

Output voltage adjustable range is 1.25V~37 Volt

Maximum output current is up to 3A, normal and stable operating current of 2A.

Press the micro switch for 3 seconds to turn off LED display, touch the button again to turn on the LED display.

The internal oscillation frequency 150KHz, belonging to the second generation of switching voltage regulator,

low power consumption, high efficiency.

Red color 7 segment display will show the input and output voltage often by pressing micro switch.

Useful to make high energy efficient variable DC power supply unit with less components.

 

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Posted by richhotrain on Friday, May 12, 2017 12:56 PM

GrandTrunk-HO

Tortoise switch machine power supply 

Mullet19

I have a 12v 1 amp power supply that plugs into the wall

It outputs 12v of filtered dc 

 
MisterBeasley

I use a 9 volt wall wart

The lower voltage causes the points to move more slowly and I like that more than a faster throw

  

richhotrain

That is good

A regulated 12 volt DC power supply is just what you need to accomplish your objective 

Sorry to inform all of you, but only very old "Linear" V-DC power supplies were regulated. (now obsolete).

All present day power supplies and wall adapters are now only "Switching" V-DC power supplies.

peahrens

 

 
GrandTrunk-HO
Sorry to inform all of you, but only very old "Linear" V-DC power supplies were regulated. (now obsolete). All present day power supplies and wall adapters are now only "Switching" V-DC power supplies.

 

Can you clarify about regulated power supplies?  Are they now unavailable, less avaliable, being phase out for some reason.  I have bought a number (two last week) of these Miniatronics regulated supplies for my building and signal lighting circuits.  It says it is regulated, which I understand to mean it should provide close to the target 12v DC at various loads up to the rated 1A.   

http://www.hobbylinc.com/miniatronics-plug-in-wall-transformer,-regulated-12v-dc-1amp-model-railroad-electrical-wt12

On my Tortoises, I used the Circuitron supply available in 2012.  I don't recall whether is was stated to be regulated, or just filtered (not the same thing).  For my Tortoises I happened to include a bipolar LED indicator at my DPDT in line with the power to each Tortoise.  The LED drop of 2v or so means the Tortoises see about 10v, with the Circuitron supply powering 21 Tortii. 

Sorry, I stand corrected. I did not realize that you can still purchase a wall AC/DC wall adaptor that is a switching power supply that is Regulated.

 ConfusedConfused

Alton Junction

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Posted by rrinker on Friday, May 12, 2017 7:48 PM

 A switching power supply is regulated. Just in a different way (actually more efficient) than a linear voltage regulator. End result is it will have a consistend output voltage across a wide load range, instead of being way over nominal voltage with only 1 Tortoise connected and well under with 15 of them.

 There is a case where the 12V supply is preferred - if you put LEDs in series with the Tortoise as indicators, they will drop the voltage, about 2.1-2.5 volts per LED, so starting with 12V results in less than 10V to the Tortoise. 2 sets of LEDs are common, one for signals and one for control panel indicators, so that's 4.2-5V drop. The Tortoise will operate much more quietly on 7-8 volts plus you will have indicator LEDs without using the contacts on the Tortoise.

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by BMMECNYC on Tuesday, May 23, 2017 8:53 PM

I just use a SPST ON-ON SPDT switch and 12VDC.  Center contact on SPST SPDT is wired to one side of the tortoise, the other side is wired to common.  The other two contacts on the SPST SPDT are +12VDC and -12VDC.   Flip switch, tortoise moves one way, flip again, it moves other way.  Easy.  LEDs can be wired up using aux contacts.  

Once I have time, I will be switching over to push buttons to facilitate the installation of Layout Command Control, using RR Circuits components.

Rule 108: In case of doubt or uncertainty, the safe course must be taken.
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Posted by JoeinPA on Tuesday, May 23, 2017 8:57 PM

BMMECNYC

I think that you mean SPDT?

Joe

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Posted by BMMECNYC on Tuesday, May 23, 2017 9:11 PM

JoeinPA

BMMECNYC

I think that you mean SPDT?

Joe

 

Yes,

Its an On-On SPDT.  Tired.

Rule 108: In case of doubt or uncertainty, the safe course must be taken.
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Posted by ROBERT PETRICK on Wednesday, May 24, 2017 8:11 PM

I am ready to wire up Tortoises. For power supply, I was/am planning to use an existing wall wart that used to power external computer speakers. It is specifically labeled 12V, 1A output. I pluged it in and measured 16.5V directly on the barrel. Is this unusual? I have two more warts, exactly alike and they read the same.

I'm almost afraid to ask (given recent activity on electrical threads), but what should I do? 

Robert 

 

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Posted by JoeinPA on Wednesday, May 24, 2017 8:38 PM

Robert

Most wallwarts will read higher than the labelled voltage until they have a load attached. Try adding a load such as a bulb or small motor and measure the voltage going to the load. You should get close to the rated voltage.

Joe

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Posted by Mark R. on Wednesday, May 24, 2017 8:56 PM

ROBERT PETRICK

I am ready to wire up Tortoises. For power supply, I was/am planning to use an existing wall wart that used to power external computer speakers. It is specifically labeled 12V, 1A output. I pluged it in and measured 16.5V directly on the barrel. Is this unusual? I have two more warts, exactly alike and they read the same.

I'm almost afraid to ask (given recent activity on electrical threads), but what should I do? 

Robert 

 

 

That means it is an un-regulated supply. As the load on it increases, the voltage will drop. These are usually designed for a specific load, where that particular load will level the output voltage to the rates 12 volts. In your case, the powered computer speakers created the proper load for a 12 volt output - what it was designed for.

A regulated supply will maintain the rated 12 volt rating independant of the load (within reason of course).

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

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Posted by mfm37 on Wednesday, May 24, 2017 9:46 PM

gone

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Posted by richhotrain on Thursday, May 25, 2017 4:30 AM

mfm37

So if the original poster cuts the coax plug off of his 12VDC power supply and connects the two wires to a DPDT reversing switch. Connects the switch's output terminals to the tortoise's end terminals (1 and 8) it will work and he can skip reading all the other blather above?

No wonder people quit the hobby.

Martin Myers

 

In the interest of accuracy and safety, if the forum moderator doesn't already have the authority to do so, he should have the authority to delete posts containing information that could damage equipment or result in personal injury to the user and his surroundings.

It makes no sense to leave such information in place, so those posts should be deleted.

Rich

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Posted by rrinker on Thursday, May 25, 2017 7:04 AM

 You know, if he was just copying and pasting from somewhere else - I kind of want to know where that somewhere else is, because they have a good bit of bad info as well. The PS514 IS regulated. The varying voltage comes from a slide switch - it's original purpose in life is a universal laptop computer replacement power supply. The old PS515 15V AC power supply wasn't regulated - it was just a transformer.

                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by ROBERT PETRICK on Thursday, May 25, 2017 7:51 AM

The instructions that came with the Tortoises say to use a simple DC supply of not more than 12 volts. I found some things in a drawer that seem to fit that description. Then I made the mistake of measuring the actual output.

I have six Tortoises on hand, and six more enroute from MBKlein. There's a holiday weekend coming up. Do I snip off the barrel plug and attach the leads to a terminal strip? Or not? And if not, where do I get something else? I've no idea where the nearest Radio Shack is, but I guarantee there is none within a hundred miles of where I am standing.

Robert

 

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Posted by rrinker on Thursday, May 25, 2017 11:06 AM

 With only a couple ot Tortoises connected, that probably won't put enough draw on that supply to drop it to 12V. I'd find a different power supply. Do you have any similar ones but marked as 9V DC output? An unregulated 9V 1A power supply will probably be around 12V with no or light load, which would be just what you need. Alternately, do you have any 1A or better diodes laying around? !N4001 types. Each one will drop about .6V - and under the load of a whopping 12 Tortoises won't even get warm. Stick 5 of them in series and you have a 3V drop. Gets you going for now and you can replace the power supply and remove the diodes later. Or do you have plans to have panel indicators? If you wire LEDs in series with the Tortoise motor terminals, that will drop the voltage to the Tortoise by whatever the LED's forward voltage is, probably 2.1-2.5 volts for a red or green LED. 

Tortoises are rated for up to 12V, but the sweet spot is more like 7-8 volts, they are a bit slower, but still have plenty of holding pwoer and best of all move quieter on the lower voltage. 12V supply plus 2 sets of LEDs (one on the panel, other as a signal or switch lantern) is good, or a 9V supply and one set of LEDs (panel indicators) is also another good option.

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by ROBERT PETRICK on Thursday, May 25, 2017 11:55 AM

rrinker

 With only a couple ot Tortoises connected, that probably won't put enough draw on that supply to drop it to 12V. I'd find a different power supply. Do you have any similar ones but marked as 9V DC output? An unregulated 9V 1A power supply will probably be around 12V with no or light load, which would be just what you need. Alternately, do you have any 1A or better diodes laying around? !N4001 types. Each one will drop about .6V - and under the load of a whopping 12 Tortoises won't even get warm. Stick 5 of them in series and you have a 3V drop. Gets you going for now and you can replace the power supply and remove the diodes later. Or do you have plans to have panel indicators? If you wire LEDs in series with the Tortoise motor terminals, that will drop the voltage to the Tortoise by whatever the LED's forward voltage is, probably 2.1-2.5 volts for a red or green LED. 

Tortoises are rated for up to 12V, but the sweet spot is more like 7-8 volts, they are a bit slower, but still have plenty of holding pwoer and best of all move quieter on the lower voltage. 12V supply plus 2 sets of LEDs (one on the panel, other as a signal or switch lantern) is good, or a 9V supply and one set of LEDs (panel indicators) is also another good option.

                           --Randy

Hey Randy-

Thanks for the straightforward reply.

The plan was to wire up the Tortoises with the existing wall warts (hey, recycling and all that) because they seemed to be labeled for what the instructions called for. The plan was to use toggles without LEDs for now and install BDL168 and SE8C later. But I've decided to go ahead and get the signaling and block detection stuff now (plus the official PS-14) and not lose any sleep.

Decisions are easy. Gathering info is a royal pain in the buttocks.

Robert 

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Posted by trwroute on Thursday, May 25, 2017 12:14 PM

I didn't go nearly as high-tech as some of you.  I just cut the end off and stripped the two wires and wired them up, and they work great with the small toggle switches that I use.  My power supply came from an old Vonage telephone box.  Quick and easy and it works great.  Nothing fancy.

This is truly one of those things that can easily be over-engineered...

Chuck - Modeling anything narrow gauge

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