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The plug in side is only two prong into the wall
That simply means there is nothing on the plug, or in the wiring, that connects to your house's ground. The two baldes are hot and neutral, with the wider blade being neutral. These are commonly referred to as "2-plug" as opposed to "3-plug." The round shaped third prong carries the house's ground up through the wiring on 3-plug wires.

OVR was simply trying to help your troubleshooting by eliminating the need to trace the 3rd wire through the transformer.

You either have 2 independent sets of wires coming from the transformer, or those braided pieces are just shielding or perhaps structural.

If you have 2 sets of wires, it is possible that the braided wires may be common, and the wires inside the more traditional insulation could both be hot, but may have different uses by whatever was being fed juice in its original application. In other words, perhaps 12v coming through the larger hot wire, while the smaller wire may by 5v.

So the test would be to set your multimeter to check for continuity. Touch one probe to one of the 2 blades that go into the electric plug on the wall. Then take the other probe and touch all the bare wires at the other end, and see which wires show continuity.

Since you don't have to worry about the 3rd prong, you are simply trying to figure out which of the 4 wires (2 traditional, 2 braided) coming out of the transformer will be connected to which prong going into the wall outlet.
 

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It was a universal power plug for laptops. Any idea which is hot/cold/ground?
Conductorkev;

Technically speaking*, the output wires from the cord you opened will not be "hot" or "ground". The output wires will carry 15-20 volts DC. One of those two wires will be positive, and the other negative. The two center wires should be checked with a volt meter set for a low DC voltage range like 20 volts DC. Touch the meter probes to the two center wires of the output cable that you cut open, while the power supply is plugged into a wall outlet. The meter should read either 20 volts DC, or -20 volts DC. If the reading is -20vdc then reverse the probes. When you get a reading of 20 volts DC the red meter probe will be on the positive output wire, (which you called "hot") and the black meter probe will be on the negative wire. (which you called "ground") As others have said, the outer mesh wire is likely a "shield" , and does not need to be used for your powering PL-10s project.


* The input plug that goes into the wall outlet is where you will have an actual "hot" of 115-120 volts AC and a "neutral" which is the AC return wire, which is at zero volts AC. Strictly speaking, There is no "ground" conductor, since the plug does not have a third prong.

Traction Fan
 

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Don't mess around with the unknown.
Just do what I did, buy from Home Depot the transformer
for a door bell. It has 18 v AC output. That powered my Capacitor
Discharge Unit. The CDU powered the 20 plus Peco
Insulfrog turnouts using Peco PL10 motors.

Don
 

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Discussion Starter · #30 ·
Don't mess around with the unknown.
Just do what I did, buy from Home Depot the transformer
for a door bell. It has 18 v AC output. That powered my Capacitor
Discharge Unit. The CDU powered the 20 plus Peco
Insulfrog turnouts using Peco PL10 motors.

Don

What something like this?


What you wire the wires in back to a plug or directly into your power and hook the cdu thru the two screws in front?
 

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Exactly. I just attached a short pair to the transformer
input wires. I plut an ordinary
lamp plug on the end. Plug it into your AC power strip.
You'll have all the power you need for your turnouts.
The output is AC but Capacitor Discharge units are
available that with rectify to DC. You use the output
of the CDU as the input to all of your twin coil or
single solenoid turnout motors. The turnout motor
coils are protected by the CDU from burnout.

Don
 

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The transformer input wires connect to the
two plug BLADES not to the tubular. There was
no ground on the transformer I used, but if
there is a ground on the one you get it's
ground wire would go to the tubular prong.

Don
 

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Discussion Starter · #35 ·
The transformer input wires connect to the
two plug BLADES not to the tubular. There was
no ground on the transformer I used, but if
there is a ground on the one you get it's
ground wire would go to the tubular prong.

Don
Ya wasn't getting that computer plug working so got the doorbell transformer and it worked on a pl11 going to try a pl10 when I get a chance. The wire instructions are not that good for them I know one side you hook together and goes to one of the poles on the spdt. Now on the other side does it matter which is the common which goes to the transformer?
 

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Make sure you use momentary contact switches for the P 10's motors. Other wise you will burn them out.
For P 10's, either side coming out of the transformer connects to the center post on the motor. The other side coming out of the transformer goes to the center post of the SPDT momentary switch. The outer posts of the switch goes to each of the outer posts of the motor.
 

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Discussion Starter · #37 ·
Make sure you use momentary contact switches for the P 10's motors. Other wise you will burn them out.
For P 10's, either side coming out of the transformer connects to the center post on the motor. The other side coming out of the transformer goes to the center post of the SPDT momentary switch. The outer posts of the switch goes to each of the outer posts of the motor.
I'm using a cdu but still using spdt. On off on.
 

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Yes, a momentary SPDT toggle would be best for
your turnout control thru the CDU. It allows for
the CDU to recharge after powering the turnout coil
Recharge happens in a split second. So you can
flip a 2nd turnout instantly after throwing the first.

Don
 

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Just to be clear, a momentary on-off-on toggle switch will return to the center "off" position on its own. So when you want to throw the points on your turnout, flip the toggle, but let it bounce back to the off position.

If you use a regular toggle, you have to remember to manually return the toggle to the off position, or the constant power to the PL10 will fry it. The momentary switches just make it a lot simpler in the long run.

The CDU sort of accomplishes the same thing. The CDU will "dump" its stored electricity, but will not send any more electricity until you flip another switch. But it's just good practice to uses momentary toggles with coil based (electromagnetic) electric switches.
 
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