# Circuit protection



## Woodwalker (Sep 23, 2016)

I'm using a 135 watt Lionel powerhouse transformer on my layout with Legacy control. Do I need to install circuit protection for the Legacy engines in case of short circuit or is the breaker on the transformer good enough. I'm just worried about frying the electronics in the engine. If so what brand or kind of breaker is recommended and should it be wired in series between the track and the transformer?


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## DonR (Oct 18, 2012)

Under ordinary circumstances, if the track is
shorted, there will be no current to the 
electronics. It's doubtful a short would 'fry'
them. However, electronics can need
a reset. A sparking short circuit could
throw the electronics into a tizzy.

Over voltage would be the most likely 
danger to your loco electronics.

Don


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## flyernut (Oct 31, 2010)

Woodwalker said:


> I'm using a 135 watt Lionel powerhouse transformer on my layout with Legacy control. Do I need to install circuit protection for the Legacy engines in case of short circuit or is the breaker on the transformer good enough. I'm just worried about frying the electronics in the engine. If so what brand or kind of breaker is recommended and should it be wired in series between the track and the transformer?


This is a great question for GunrunnerJohn. He is, IMHO, a electrical genius!!!


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## AmFlyer (Mar 16, 2012)

I am not familiar with the transformer you are using. I never run my Legacy engines with a postwar transformer, only with modern power supplies with the correct fast acting circuit protection such as a TVS. No breaker will trip fast enough to protect the electronics in the engines.


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## Woodwalker (Sep 23, 2016)

So what transformer or circuit protection should i use explain to me so I can understand since I'm new to model railroading. What is TVS?


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## AmFlyer (Mar 16, 2012)

As I said earlier I use modern transformers which are correctly protectected. If you want to add a TVS to your wiring do a forum search on transient voltage suppressor. The second page of the 6th thread down from the top has a link to the correct part number provided by gunrunnerjohn.


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## gunrunnerjohn (Nov 10, 2010)

The Lionel PH135 doesn't have that great a circuit breaker, it's a thermal breaker that's pretty slow to react unless it sees a fairly massive overload. I sold all my PH135 bricks and upgraded to the PH180 brick with the electronic breaker. I also bought enough PH180's to take on the road with the modular club layout.

I do recommend external protection for the PH135, and the TVS that Tom recommends is also an excellent idea in addition to the better breaker. The TP1.5KE36CA is what I use for O-gauge trains.


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## Woodwalker (Sep 23, 2016)

Thanks for all the good info. I think maybe the best way to go is get the 180 watt powerhouses with the better protection. Ive seen a couple good deals on eBay for the ZW with two 180s slightly used. I think they are called the multi watt kits.


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## gunrunnerjohn (Nov 10, 2010)

I have one of those, mine has the optional meter attachment. Lazy man's pictures, I didn't feel like taking a picture of mine.


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