Turnouts
Electrofrog vs Insulfrog Turnouts
Quick answer
Electrofrog, live-frog turnouts eliminate stalling on short-wheelbase locomotives but must be wired correctly or they short; Insulfrog, dead-frog turnouts are simpler to wire but can stall small switchers crossing the gap. Peco HO Scale Code 83 Electrofrog Number 6 Right-Hand Turnout is the electrofrog option; Atlas HO Code 83 Number 6 Left-Hand Super Switch stands in for a dead-frog design.
Peco HO Scale Code 83 Electrofrog Number 6 Right-Hand Turnout
$44.59A live, powered frog that eliminates stalling on short-wheelbase locomotives, but needs correct wiring.
Best for: reliable slow running over the frog, with correct wiring
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Atlas HO Code 83 Number 6 Left-Hand Super Switch
$27.40An isolated, unpowered frog like Insulfrog’s, simpler to wire out of the box but able to stall small switchers.
Best for: main line and passing siding work in HO
Check price on AmazonThe verdict: electrofrog is the better performing choice for anyone running short wheelbase switchers or slow, deliberate switching operations, but it demands correct wiring or it will short the layout, while a dead-frog design like Insulfrog is simpler to wire and forgiving of mistakes at the cost of an unpowered frog gap that can stall exactly that same short wheelbase equipment. Peco's Electrofrog and Insulfrog names are the company's own trademarks for live-frog and dead-frog turnouts, and the underlying live-frog-versus-dead-frog choice applies across the hobby beyond Peco's specific product line.
Peco HO Scale Code 83 Electrofrog Number 6 Right-Hand Turnout is a genuine Peco Electrofrog turnout, with a frog that is powered and polarity-switched by the points. The catalog does not carry a Peco Insulfrog model in this exact size, so Atlas HO Code 83 Number 6 Left-Hand Super Switch stands in here as an example of the dead, isolated frog design that Insulfrog also uses, even though it is not sold under the Insulfrog name.
On this page
- What is the actual difference between a live frog and a dead frog?
- Why does a dead frog cause short wheelbase locomotives to stall?
- What does it take to wire an electrofrog turnout correctly?
- Which frog type should a beginner choose?
- Electrofrog vs dead frog (Insulfrog-style), side by side
- Which one should you actually buy?
What is the actual difference between a live frog and a dead frog?
A live, or powered, frog carries track current across the frog casting itself, with its polarity switched automatically as the points move, which keeps power flowing continuously under a locomotive's wheels as it crosses. A dead, or insulated, frog has no current running through the frog casting at all, so any locomotive whose wheels momentarily bridge only that gap, with no other wheelset making contact elsewhere, loses power for that instant. Peco brands its live-frog turnouts Electrofrog and its dead-frog turnouts Insulfrog; other manufacturers use the same two frog types under their own naming.
Why does a dead frog cause short wheelbase locomotives to stall?
A short wheelbase switcher, particularly a small steam switcher or a diesel with a short frame, can have all of its pickup wheels crossing the dead frog gap at nearly the same moment, leaving no wheel elsewhere on the locomotive making contact with powered rail during that instant. The locomotive briefly loses power and can hesitate or stall right at the frog, an issue that gets worse at slow switching speeds where momentum is not carrying the locomotive through the gap.
What does it take to wire an electrofrog turnout correctly?
An electrofrog turnout needs its frog polarity to switch in step with the points, and depending on the specific turnout and switch machine, that can require an auxiliary switch or relay to change the frog's polarity reliably as the points throw, plus careful attention to isolating the frog rails from adjacent track sections that carry the opposite polarity. Get this wrong and the result is a dead short the moment the points are set one way with a wheel bridging the wrong rails, which is the real tradeoff electrofrog asks a builder to accept in exchange for its stall-free running.
Which frog type should a beginner choose?
A dead, insulated frog design is the simpler and more forgiving starting point for a beginner, since it works reliably out of the box with straightforward wiring and no risk of a short from incorrect frog polarity. A builder running short wheelbase switchers who is comfortable with the extra wiring step, or who is frustrated by stalling on a dead-frog layout, is the one who should move to electrofrog turnouts specifically at the locations where that stalling actually happens.
Electrofrog vs dead frog (Insulfrog-style), side by side
Electrofrog eliminates the stall risk a dead frog creates for short-wheelbase locomotives, but only if its frog polarity is wired correctly.
| Factor | Electrofrog (live frog) | Insulfrog-style (dead frog) |
|---|---|---|
| Frog powered | Yes, polarity switches with the points | No, isolated |
| Stall risk for short-wheelbase locomotives | Low | Higher |
| Wiring complexity | Higher, needs correct polarity switching | Lower, works reliably out of the box |
| Risk if wired incorrectly | Short circuit | None, just possible stalling |
Which one should you actually buy?
Buy Peco HO Scale Code 83 Electrofrog Number 6 Right-Hand Turnout wherever short wheelbase switchers or slow, deliberate switching moves cross a turnout regularly, and be ready to wire its frog polarity correctly using the guidance at how to wire a DCC layout. Choose a dead-frog turnout for the rest of the layout, particularly a first layout or any section where simple, reliable wiring matters more than eliminating an occasional stall on the smallest equipment.
Frequently asked questions
What does Electrofrog mean on a Peco turnout?
Electrofrog is Peco’s trademark name for its live, powered frog turnout design, where the frog carries current and its polarity switches automatically as the points move. This eliminates the stalling that a dead frog can cause for short-wheelbase locomotives, at the cost of needing correct polarity wiring.
What does Insulfrog mean on a Peco turnout?
Insulfrog is Peco’s trademark name for its dead, insulated frog turnout design, where the frog carries no current at all. It is simpler to wire and works reliably out of the box, but a short-wheelbase locomotive can briefly stall if all its pickup wheels cross that dead gap at once.
Do all manufacturers use the Electrofrog and Insulfrog names?
No, those are Peco’s own trademarked names for a live frog and a dead frog turnout. Other manufacturers, including Atlas, use dead-frog or live-frog designs of their own under different names, but the underlying electrical concept, powered versus unpowered frog, is the same across brands.
Will a dead frog turnout definitely stall my locomotives?
Not definitely. Stalling depends on the locomotive’s wheelbase and how many wheels pick up power at once; a locomotive with pickup on multiple widely spaced axles is less likely to lose contact entirely at the gap than a very short wheelbase switcher is.
Is it hard to convert a dead frog turnout to a live frog?
Generally you cannot convert one design into the other after purchase, since the frog casting itself is built differently for live versus dead frog operation. The choice is made at the point of buying the turnout, not as a later modification.
Can electrofrog turnouts cause a short circuit?
Yes, if the frog’s polarity is not switched correctly in step with the points, or if the frog rails are not properly isolated from adjacent track carrying the opposite polarity. Correct wiring, often with an auxiliary switch or relay, avoids this risk entirely.
Researched, not professional advice. This page is compiled from published manufacturer specifications, instruction manuals, published NMRA standards and recommended practices, and owner-review consensus, not hands-on testing. Figures described as a rule of thumb are hobby convention rather than a standard, and they are labelled that way wherever they appear. Always check a radius, a clearance or a grade against your own equipment before you cut wood or lay rail, because manufacturers vary and so does what your specific models will tolerate. Any permanent mains wiring in a layout room is work for a licensed electrician to your local code.