PECO Eletrofrogs and DCC

[rrinker]

Yes follow the instructions on Wiring for DCC. All good stuff.

But let me add, the problem is NOT that the frogs are powered. This is not what makes a turnout DCC 'unfriendly'. The real problem is that both point and closure rails take the polarity of the stock rail they are against. That means you have two rail with opposite polarity a mere flangeway width apart. Wheels that are close to or too tight in back to back gauge will likely make contact. On DC power, this usually isn't a problem, you never even see it. But a DCC booster has a much quicker reacting short mechanism, and things like this will trip the protection, sopping everything on the layout (or in that power district, if you have broken your layout up). Also, a loco approaching the turnout against the set route, the instant it crosses the gap required by a live frog turnout, is now ALSO causing a direct short.
Trainign the operators stops the second part. Stopping the first thing requires the modifications as shown on the Wiring for DCC site.

--Randy

[simon1966]

http://www.wiringfordcc.com/switches_peco.htm

Follow this link to a great reference for what you need to know

[mcouvillion]

I didn't "snip" anything when I wired our club layout and we used about 50 Peco Electrofrog turnouts. You might be referring to converting an as-purchased turnout to DCC-friendly before laying it. If that is the case, you will need to change the way the power is routed to the point rails, as it is "power routing" and both points and the rails to the frog from the points, and the frog, are the same polarity as the rail the point rails are contacting. This is the reason it is considered DCC-unfriendly, as the point not touching the stock rail is the opposite polarity and is only a fraction of an inch from it. Metal wheels passing between the two can touch, and form a short circuit, if the back side of the wheel flange touches the point rail at this location. DCC-friendly involves cutting the existing bare jumper wires under the turnout that power the point rails and cutting the rails to the frog, electrically separating the two rails from each other and from the frog, and then jumpering them to the adjacent stock rails. This way, each point rail is the same polarity as its adjacent stock rail all the time. You will still need to power the frog from a SPDT switch attached either to the ground throw or switch machine activating the turnout. The rails past the frog will need to be electrically isolated from the attached rails by insulated rail joiners.

I hope I described this adequately. I don't have an actual turnout on hand to tell you EXACTLY what you would need to cut. Let me know if you have another question.

Mark C.

[Don Gibson]

The GOAL is to insulate the frogs.

cut gaps in the point rails - isolating that side of the frog.
chice of doing same on other side of frog, or using insulated rail joiners's on inside 'V' rails. NOTE: this cut off electiciiy to the frog and frog rails.Power them via electrical SPDT points from a switch machine..

[Anonymous]

How do you wire PECO electrofrog switches for dcc? I have read some articles, but they say snip here and jump there. I think I understand the "jump there " part. I just can't see anything on the switch to "snip". What am I missing?