# Wiring turnout motors



## JeffHurl (Apr 22, 2021)

Hi everyone,

I have searched, and didn't come across anything that helped me, so I thought I'd just ask the experts.

My N scale layout will include 10 (maybe 12) turnouts. I plan to use PECO code 80 track and turnouts, and want the turnouts to be powered remotely using their PL10 turnout motors. There will be no reverse loops, or any other things that would require reversing polarity, so the wiring should be fairly straight forward.

I will be using on-off-on momentary toggle switches to control the motors/turnouts, and have read that a Capacitive Discharge Unit (CDU) is wise to incorporate into the wiring scheme.

1) Can anyone help me understand how to incorporate a CDU? Is one unit sufficient? If so, where do you put it in the wiring scheme?
2) I have no issues with reverse loops or wyes. My train will always travel in the same direction, and all turnouts will either lead to a spur, or to a another loop. Given this type of layout, is there any reason to use Insulated frog turnouts versus electrified frogs?

Thanks in advance!


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## traction fan (Oct 5, 2014)

JeffHurl said:


> Hi everyone,
> 
> I have searched, and didn't come across anything that helped me, so I thought I'd just ask the experts.
> 
> ...


JeffHurl;

Peco is an excellent brand choice for turnouts. Both the turnouts themselves, and the PL 10 switch machines, should give you years of reliable operation.
Yes, using a CDU is a wise precaution. One CDU will handle all your turnouts. It is wired between the power source for the turnouts, and the hot feed wire that goes to the center terminal of all your turnout-controlling toggle switches.
One of those little black "wall wart" power supplies, such as those used to charge a cell phone, will do nicely. The DC output voltage from the wall wart (12-18v) charges up the capacitor in the CDU. When you move one of your spring-loaded toggles to one of the routes, the capacitor puts out a powerful instant burst of power to the coil of the PL-10 that is connected to that side of the toggle switch.
The automatic protection comes into play because the CDU can't recharge until the toggle is back in the center, "off" position. Even if someone holds the switch over for more than a second or two, or even if the toggle switch shorts out internally, the coils of your PL 10 will not burn out. Peco actually sells a CDU to be used with their turnouts.

On disadvantage of using spring-loaded, center off, toggles is that there is no indication on the control panel showing which way the turnout points have been set, unless you wire up indicator lights, since the toggle switches' handle will always return to the center position.

An alternative system would be to use simple toggle switches which are not spring loaded, and don't have a center off position. The way the toggle switches' handle is set, shows which route through the turnout has been selected. If you want an even more obvious indication, use DPDT (Double Pole Double Throw) toggle switches. One set of switch contacts can operate the turnout, and the other set can operate indicator lights on the control panel.

The electrical problem of having this type of toggle switches "on" constantly, is overcome by wiring a momentary, doorbell-type, button between the CDU's output, and the hot feed wire that goes to the center terminal of all the toggle switches. To operate any given turnout you simply flip the appropriate toggle switch toward the desired route, and then push the button. Use a pushbutton and toggle switches with reasonably good current ratings, 1 amp DC minimum but higher would be better. Disregard the AC current ratings as your CDU will be pumping a lot of DC current through the button & switches.

Whether to use Peco's plastic frog (Insulfrog) or metal frog (Electrofrog or Unifrog) turnouts depends on the type of locomotives you plan to run.
Most current production locomotives pick up power from all their wheels.
Such an "all wheel pickup" locomotive will sail right through a plastic frog turnout, because even when some of its wheels are on the plastic frog, other wheels are still on metal rails, and still picking up power.

On the other hand, small, switcher-type, locomotives that have only a few wheels, or older models of big locomotives that only pick up power through a few of their wheels, may stall on a plastic frog.
A metal frog turnout (Electrofrog, or Unifrog) can have the frog powered, and that helps locos with limited power pickup get through the turnout smoothly.
A powered metal frog will be the right rail for one route through the turnout, but the left rail for the other route. For this reason, the electrical polarity of the frog needs to change, depending on which route is selected. Peco sells a set of electrical contacts that drop over the actuating rod of their PL 10 switch machine. These contacts can be wired to change frog polarity.

The file below has more info on turnouts.

Good Luck & Have Fun;

Traction Fan 🙂


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## DonR (Oct 18, 2012)

The CDU circuit described by Tractionfan will work fine.
However, as he indicated, it won't easily control panel
or trackside signals. One of the easiest and
safest turnout control to use is the Stapleton 751D.
It is a toggle switch device that throws the points
thru a built in CDU and controls the LED signals.



751 SERIES ELECTRONIC TURNOUT SWITCHES



Don


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## JeffHurl (Apr 22, 2021)

Thank you both!

I'm going to make a switch panel out of 1/8" Luan. I plan to use mod podge to place a print-out of my layout on the surface of the luan, and insert the toggle switches into holes drilled where the turnouts will be. At least that way, I can actuate the points in the direction I want the train to go with a good visual reference. I thought about the LED indicators, but that's a little beyond my comfort zone as far a assembling.

I have a lot of old "wall warts" that I can use to charge the CDU. I'm sure there is at least one 12v and maybe one a little more powerful. Do you know approximately how long it would take a 12v wall charger to charge the CDU? I envision switching a few turnouts at a time as I plan to re-route the train, and don't want to have to wait too long between throws. Also, can I just use the accessory outputs from my DC transformer to do that, or am I better off with just using the wall wart?

Thanks again for the feedback, I really appreciate you both taking the time to help out a newbie.


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## traction fan (Oct 5, 2014)

JeffHurl said:


> Thank you both!
> 
> I'm going to make a switch panel out of 1/8" Luan. I plan to use mod podge to place a print-out of my layout on the surface of the luan, and insert the toggle switches into holes drilled where the turnouts will be. At least that way, I can actuate the points in the direction I want the train to go with a good visual reference. I thought about the LED indicators, but that's a little beyond my comfort zone as far a assembling.
> 
> ...


 The Stapleton 751D that Don suggested is a good product, but you might check the cost of that option. I think buying 10-12 of the Stapleton controllers would be more expensive ( $8.75 ea. factory assembled, or $ 5.50 ea. in a 10 pack of kits) albeit the 751D does include the toggle switch, and CDU, so add those costs in any comparison. 

The recharge time of the CDU should only be a few seconds. Don has used his home-made CDU with a layout full of Peco Electrofrog turnouts for many years. If you ask him nicely, he might send you the schematic.

The accessory output of a typical DC power pack is AC, not DC. You might need a diode, or bridge rectifier to convert the AC accessory output to DC. Some wall warts are also AC output, though most output DC. Just about any wall wart that puts out 12-18 volts DC should work fine.

You mentioned "switching a few turnouts at a time." You can simply set all the toggle switches to the desired route first, and then push the button. Most CDUs should be able to handle 2 or 3 turnouts simultaneously.
If this causes problems, or if you need to operate say 6 or 7 turnouts at once, then you will need a bigger capacitor in a home-made CDU, or a more powerful commercial CDU like the "Snapper" sold by Walthers. www.walthers.com 

Traction Fan 🙂


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## DonR (Oct 18, 2012)

It is possible to switch more than one turnout with the same 'button'.
This particularly is helpful if you have a yard with several spurs.
It uses a 'Diode Matrix' circuit. It sounds complex but it isn't.
You just need a number of small diodes and a barrier terminal
strip to connect to your panel. Push a button in the spur you want to use, the system
sets all points for a clear route. It does require that you
use twin coil turnout motors.

CDU units instantly recharge. There is no waiting.
I'd have to search to see if I still have the wiring 
diagram of the unit I used. I powered it with a
typical home door bell transformer from Home depot.
Flipping more than one turnout at a time does take
a bit more oomph than a typical wall wart puts out.

Don


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## traction fan (Oct 5, 2014)

DonR said:


> It is possible to switch more than one turnout with the same 'button'.
> This particularly is helpful if you have a yard with several spurs.
> It uses a 'Diode Matrix' circuit. It sounds complex but it isn't.
> You just need a number of small diodes and a barrier terminal
> ...


Don;

In my last response, I was about to suggest the diode matrix idea too. Then I remembered that the OP planned to use toggle switches, rather than multiple push buttons.
Whether he used the spring-loaded, center off, type he originally had in mind, or the conventional, ON-ON toggles, and a single master push button, the simple diode matrix wouldn't be all that appropriate.
While it would be possible to wire a diode matrix to the spring-loaded toggles, which toggle would he operate? He would need to have the toggles set up for routes, rather than individual turnouts. He would also be back to the "no panel indication of which turnout is set which way."

In the case of the conventional ON-ON toggles, a matrix would be unnecessary, since the toggles for the route could be set before pushing the button.
That diode matrix works fine with a pair of push buttons for each turnout, or each yard track/route, but it would be harder to adapt to toggles. The OP has nixed indicator lights on his control panel, and I think he wants to keep things simple.

regards;

Traction Fan 🙂


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