PECO Unifrog

DCCWiki, a community DCC encyclopedia.

The PECO UNIFROG is a new turnout design from PECO. Right out of the package it will behave like a PECO Insulfrog turnout.

Unifrog detail.jpeg

PECO plans to replace the Electrofrog and Insulfrog products with their Unifrog. This will happen over time. Doing this allows PECO to eliminate two products and replace them with one. As of 2018 only a limited selection of Unifrog turnouts are available, but this is expected to expand with time.

There is additional information on the Turnout page.

Introduction to the PECO Unifrog

With Electrofrog and Insulfrog, modellers were able to make good looking and functional trackwork. The decision of Electro or Insulfrog had to be made at the time of purchase. After purchase, how you wire them is up to you.

Unifrog Description

For ease of identification, the PECO part number has a U to indicate Unifrog in the part number on the packaging. Example: ST-U750 is a Unifrog RH turnout, O Scale.

As shown in the picture above, the Uniform has a metal frog, like the Electrofrog. The difference is that the frog is constructed with gaps, filled with plastic, to isolate it from the rest of the turnout.

Out of the package you will see a wire wrapped around the turnout near the toe of the frog. This wire is connected underneath the frog to the frog rails themselves. You can choose to connect it or not, so you have a powered or unpowered frog.

If you flip the Unifrog over, you will see that they have wires connecting the closure rails to the appropriate stock rail, eliminating the potential of a short should a wheel bridge the gap between the switch and stock rails. Perfect for DCC operations. This also eliminates a failure point, as a mechanical connection using the switch rail isn't needed for power.

The point rails are also connected to their matching stock rails.

Advantages of the Unifrog Design

  1. DCC Ready, right out of the package
  2. No mechanical connections needed between switch and stock rails
  3. Dead or Live Frog operation
  4. Switch rails do not change phase depending on the frog's state
  5. Insulated rail joiners not required on the point rails to prevent a short caused by power routing
  6. Can be converted to Live or Dead frog without removal, by simply connecting or disconnecting the wire feeding the frog
  7. Only the stock rails need to be connected to the power bus

Disadvantages of the Unifrog Design

  1. The frog is dead unless powered
  2. No power routing as in the Insulfrog, should you want to run analog DC
  3. Possible mechanical short at the point rails (wheel tread bridging point rails)
Conversion to Insulfrog Operation

If you want the Unifrog to behave like an Insulfrog, you simply need to snip the wires underneath connecting the stock rails to the closure rails. This isn't required for DCC operation, but can be done in seconds prior to installation.

What is the Difference between Unifrog and Previous PECO Turnouts?

The revolutionary aspect of the Unifrog is that you can change your mind. You can install them in them as they come (a dead frog as in the Insulfrog), then later decide to switch over to a live frog (Electrofrog). With the Unifrog this can be done without having to buy new turnouts. In fact, you do not even have to lift the track to re-wire the turnout.

Unifrog Availability

Currently the PECO Unifrog turnouts are limited in selection. PECO has released an N Scale "medium radius" SL-U395F and SL-U396F turnouts, and for HO the SL-U7061 and SL-U7062 #5 turnouts. For 00, they have released Bullhead rail products in the form of a Double Slip, Single Slip and Long Crossing.

As tooling is replaced, more Unifrog turnouts will come on the market.

Wiring the PECO Unifrog

There are two options

  1. Install it directly from the package. The frog remains insulated from the closure and point rails and requires no extra wiring
  2. Use the pre-attached wire to connect the stock rails to the frog using an electrical switch

Wiring for DCC

Wiring the PECO Unifrog for DCC is not much different than wiring any other turnout

  1. Connect the appropriate stock rail to the appropriate wire on your power bus
  2. Power Routing of the Frog:
    1. Attach the supplied wire to a Frog Juicer, toggle switch, Tortoise motor or other device with can switch connections to the power bus
    2. If you don't plan on doing that right away, but may in the future, attaching a short length of wire to the pigtail provided may make life easier later
  3. Optional: For reliability, connecting the switch and closure rails with a small jumper (Competency at soldering is a must here)

Power Routing

The PECO Unifrog is not power routing.

From the factory, the point and closure rails are wired accordingly for proper operation. The closure rail is also wired to the adjacent stock rail. As such, insulated rail joiners are not required on the point rails.


PECO Announcement

From PECO:

The wiring of these new turnouts is a development of both the Insulfrog and Electrofrog designs.

For current users of the Electrofrog or Insulfrog versions of our turnouts the new Unifrog gives modellers the best of both worlds. As supplied, the turnout is wired completely “live”, except for the frog tip and wing rails, and can be used straight out of the packet without any further modification (and so behaves like an Insulfrog).

The stock rails are wired to the closure rails at the factory, which in turn are connected to the corresponding frog rail. This means the turnout is completely live (except for the tip of the frog), no extra wiring required. If the turnout is being used as a switch to isolate a section of track then it is simple job to remove the wire that joins the centre rail and stock rail and it will work like a current Insulfrog. Peco provides a pair of pigtails to allow wiring the turnout to behave like an Electrofrog. (They have been spot welded onto the appropriate places.)

To change frog polarity the PL-13 or PL-15 change-over switch/microswitch, or the SmartSwitch SmartFrog PLS-130 with do the task. A Frog Juicer or a mechanical switch would also work.

Help Needed

Anyone who has purchased a Unifrog can take photographs to illustrate this article. It would be appreciated.