Peco Streamline Unifrog Points on a DC layout

[dataylor1958]

I am making an analogue design with two concentric ovals and a shunting area. I will have a controller for each oval and they will be joined by Peco Streamline Unifrog points. I plan to use the points as they come out of the packet with no additional wiring. I assume that I will need insulating rail joiners where the points from one oval join the point on the other oval? I see lots of advice indicating that IRJs are not required but I assume that is for DCC? I have attached my track plan.

[Tricky Dicky]

You are correct that IRJs are not required as in electrofrog points where the whole of the V making up the frog needs to be same polarity as the direction of travel. On unifrog points only the very tip of the frog needs to match the appropriate polarity the remaining rails making up the V are insulated from the tip. If you use IRJs on those V rails they will remain completely dead (unpowered).

DC or DCC it is no different. If you choose not to wire a switch to change the frog tip polarity the point will behave like an insulfrog point with the tip being unpowered which should not be an issue except perhaps for some short-base locos. Wiring the point tip with a polarity changing switch will improve run through for all types of loco just like an appropriately switched electrofrog point.

There are a number of videos on YouTube on wiring unifrog points just put unifrog points in the search facility in YouTube it includes a useful explanation from Peco TV about the difference between all the three types and how the polarity changes or not depending on type used.

Richard

[RFS]

But surely the OP's question is not about switching frog polarity, but maintaining electrical separation between his two ovals of track each having their own DC controller? In this scenario, you do need IRJs between the two points forming the crossover to keep the two independent power supplies apart.

[dataylor1958]

But surely the OP's question is not about switching frog polarity, but maintaining electrical separation between his two ovals of track each having their own DC controller? In this scenario you do need IRJs between the two points forming the crossover to keep the two indendent power supplies apart.

Thank you, you answered my question.

[Tricky Dicky]

Apologies for the bum steer, RFS is right about the need for IRJs when using two controllers as in your case. I kinda glazed over that bit and focussed too much on you not needing to do additional wiring. I cannot even blame a festive tipple for not reading the post correctly

Straight out of the package they are like insulfrogs with the option of adding a polarity switch for the tip of the frog. Feeding a siding does not require IRJs as the two V - rails are not joined and therefore their polarity remains constant, however separation is required on the branching rails when moving from one controller to another

Sorry again for not reading the post correctly.

Richard

[dataylor1958]

Thank you for your reply and happy new year