Insulfrog Vs. Electrofrog

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firstBL2

New Member
What type of turnout is more DCC friendly? Does it matter what type of turnout I use when wiring a reverse loop?
 

CP9302

Member
A reverse loop is when the track rejoins itself at the switch. The through track loops around and conects to the diverging rout of the switch. This has the effect of reversing the direction of the train and also the polarity of the rails. The outside rail goes around and becomes the inside rail. This causes an electrical short. Both rails have to be gapped and some form of polarity reversing must be done. DCC has modules to handle reversing automatically. You can also use a DPDT switch to reverse polarity manually.

Insulfrog switchs have an insulate frog, it is un-powered. This is the best option for DCC.

Electrofrog switches are power routing and supply power to the frog. They provide power to the frog and frog rails based on how the switch is thrown. This is great for stub sidings in DC, but is worthless in DCC. Electrofrog switchs are a pain in the @$$ to use in DCC, because you have to insulate the frog anyway to prevent shorts.
 

UP2CSX

Fleeing from Al
A reverse loop is when the track makes a loop and then returns to the same starting track. This means the the current from the starting track will meet the same current on the return track, causing a short circuit. Reverse loops are neither good or bad, since some layouts will require a reverse loop to function. You just have to wire it so the loop section can have the polarity reverse before the train gets back to the starting track. With DC, this is done by having gaps within the loop and wires that go to a switch that allows you to reverse the polarity on the other side of the gap before the train gets to the potential short circuit. With DCC, this is somewhat easier because you can buy reverse loop modules that don't require additional wiring or throwing a switch at the right time.

Insulfrog and Electrofrog are Peco trademark names for two common types of turnout. The Insulfrog has a "dead" frog that doesn't conduct electricity. The power is routed by which way the points of the switch are thrown so one route will always have power and one route will have no power. The Electrofrog has power that is routed through a "live" frog. Since the frog always has power, the position of the points on the switch don't matter - both routes always have power all the time.

There is a debate as to whether or not dead or live frog switches are more "DCC Friendly". My experience is that either of the types generally work fine. There are some rare issues that can take place with a live frog turnout in DCC but it's not a reason to change all your turnouts if you want to switch to DCC.
 

Selector

Well-Known Member
What is a reverse loop and can someone define the difference between the two insulfrog vs electrofrog?
A reversing loop is a section of track that does two things, both necessary for the description: it brings a train back through a diverging route that rejoins rails just left, but it is also necessary that the power transferring axles on the rolling item that regains the original track have axles astride what amount to opposite polarities in close proximity to each other...such as at a frog point, or at the points rails when power is routed that way.

The insulfrog turnouts are deemed "DCC friendly" because they keep shorts away from the frog by denying it power. With all the various metal rails there, and with variances in the gauge of items in, around, and above the frog, not the least of which would be powered axles and metal wheels, there will come a time when something metallic bridges across polarities if the frog gets power from the points rails. With an insulated frog, the inadvertent bridging is innocuous because there is no power to short from metal to metal. Once the axles regain powered rails, the separation between the polarities is statistically too great to cause any worry...no physical contact.
 

SpaceMouse

Fun Lover
This is great for stub sidings in DC, but is worthless in DCC.
Not entirely true. If you run small steam like in the 1800's, they will not make it across an insulated frog without losing power.
 

traingeeks

New Member
Okay, here's the rookie question. So I wanted to keep this 2nd track as a staging track to park trains on 1 cab, which switches should I use? I wanted to be able to run the same cab to the stage track but once parked and the switch turned on back to the main line, the train on the stage track won't run. How can I accomplish this? Red arrow is the stage track. See my picture. By the way I am on DC now but may go to DCC
 

UP2CSX

Fleeing from Al
You can either use a turnout which has a non-powered frog, like the Peco Isulfrog or you can cut gaps in the rail just behind the turnout on the side track. You would then run two wires from your transformer through a double pole, double throw (DPDT) switch. The wires from the DPDT switch would then be soldered, one to each rail, on the side track. You would flip the switch one way to provide power to the side track and the other way to cut power to the side track. If you go to DCC, you would then leave the track powered all the time since the locomotive control will come from the DCC power center rather than the turnout.
 

traingeeks

New Member
You can either use a turnout which has a non-powered frog, like the Peco Isulfrog or you can cut gaps in the rail just behind the turnout on the side track. You would then run two wires from your transformer through a double pole, double throw (DPDT) switch. The wires from the DPDT switch would then be soldered, one to each rail, on the side track. You would flip the switch one way to provide power to the side track and the other way to cut power to the side track. If you go to DCC, you would then leave the track powered all the time since the locomotive control will come from the DCC power center rather than the turnout.
Ok, now I'm confused. All turnouts are #6 PECO Insulfrog 2 LH and 2 RH. I ran the train to the staging side, and it stopped. Once i connected the 2nd cab to the staging track it started again. So I guess it isolating the current. So I wanted to have the train continue to move into the stage track. So I would need some other switch and another wire from the controller to the switch to the stage track and only flip the switch when using it? :confused:
 

UP2CSX

Fleeing from Al
OK, I guess I misunderstood. If you just want to spot trains on that siding and not run anything there, the Insulforg turnout is all you need since lining the switch for the main will shut off power to the siding. If you want to have trains moving on both tracks you will need two transformers, with the wires from one connected to the siding track right behind the turnout. You won't need a DPDT switch because the second transformer will act as a a switch when you have it on or off.
 

traingeeks

New Member
OK, I guess I misunderstood. If you just want to spot trains on that siding and not run anything there, the Insulforg turnout is all you need since lining the switch for the main will shut off power to the siding. If you want to have trains moving on both tracks you will need two transformers, with the wires from one connected to the siding track right behind the turnout. You won't need a DPDT switch because the second transformer will act as a a switch when you have it on or off.
Ok, now this make sense. THANK YOU ALL for your postings. I just have to think like electricity. This is such a cool hobby, much to learn.
 




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