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After this weeks debacle with my ZW and a derailment with a resulting short circuit, I have been reading up on circuit protection for older postwar transformers. I mostly run conventional locos, so I would like to stay with a postwar transformer (plus I have a KW sitting around)!

I was reading up on the psx-1 circuit breaker. Seems like most people are using them in conjunction with a DCC application. Can this be used without DCC or any other fancy electronics? I was hoping to wire in a circuit breaker between the transformer and the track to help prevent another blowout.

Thanks again!

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ADCX Rob posted:

An amp is an amp, if you are looking at breaker protection. If you want to use breakers on each of the outputs of the ZW, that are rated somewhat below the 15 amp main thermal breaker, there are many inexpensive but reliable options. First choice would be the Lionel #91 adjustable magnetic breaker.

I have used the Re-Cirk-It type breakers in various ratings for many years, here is a 2.5 amp type.

RECIRKIT

Thanks! Is 2.5 amps enough or should I look for something with some more power?

IMHO, the main difference between thermal breakers and electromagnetic breakers is the trip time.
An electromagnetic breaker, like the Postwar Lionel #91 will trip instantly.
A thermal breaker takes some time while the bimetallic strip heats up.

Some folks say the delay is an advantage, to each their own.

Maybe there are some solid state breakers that trip quickly. If so, I am not familiar with them. One of the folks with better knowledge would have to comment.

Tfabrizio posted:

After this weeks debacle with my ZW and a derailment with a resulting short circuit, I have been reading up on circuit protection for older postwar transformers. I mostly run conventional locos, so I would like to stay with a postwar transformer (plus I have a KW sitting around)!

I was reading up on the psx-1 circuit breaker. Seems like most people are using them in conjunction with a DCC application. Can this be used without DCC or any other fancy electronics? I was hoping to wire in a circuit breaker between the transformer and the track to help prevent another blowout.

Thanks again!

You want the PSX-AC, not the PSX-1. Folks on the forum swear by them. They are a little pricey though.

Also, if you are running any trains with electronics, add a TVS to your track lock-on. There are several threads that discuss this on the forum.

George

Last edited by George S
Tfabrizio posted:

Thanks! Is 2.5 amps enough or should I look for something with some more power?

That's a question only you can answer - and it depends on your wiring and what you are trying to protect from over current conditions.

The similar 6 amp breaker used on the RS-1 seems to be a good compromise between protection & no nuisance trips.

I have bought 7 amp circuit breakers from Mouser Electronics, www.mouserelectronic.com to use with my post war ZW. They are fast acting, much faster then the post war ZW's circuit breaker and less expensive then the other type of breakers mentioned by others on this posting.

Any way the post war circuit breaker is a 15 amp breaker on the common side and can take several seconds to almost half a minute to trip and that's why I use external 7 amp breakers with my post war ZW. I have one breaker on each hot terminal(A, B, C & D), I wired them in series between the transformer and the track hook-up.

Lee Fritz

phillyreading posted:
Tinplate Art posted:

Do not forget spike protection on the track side of the transformer.

If you use the older post war transformers with newer engines then you must have some kind of protection like a TVS (transient voltage suppressor)unit rated around 32 volts and must be bi-directional.

Lee Fritz

Thanks. I see how to wire a tvs in with a traditional lockon, but how do you wire one in for fastrack?

The The recommended TVS' are in the list below.

PTC and TVS - Some Commonly Used Sizes and Part Numbers (from other threads)

And as George S stated, the PSX-1 is for DCC only and you would want the PSX-AC for O gauge trains using AC track power. That is, if that ends up being your choice here. The PSX-AC also has voltage spike protection, but a few TVS doides here and there on your layout might still be worth adding as well. They are cheap.

 

Tfabrizio posted:
phillyreading posted:
Tinplate Art posted:

Do not forget spike protection on the track side of the transformer.

If you use the older post war transformers with newer engines then you must have some kind of protection like a TVS (transient voltage suppressor)unit rated around 32 volts and must be bi-directional.

Lee Fritz

Thanks. I see how to wire a tvs in with a traditional lockon, but how do you wire one in for fastrack?

You could add a crimp on connector to each end of the TVS to allow attachment to the underside tabs of the fastrack - the same connectors used for your terminal wires.

Those exact connectors (.110 crimp connector) are available on Ebay in packages of 100 or so as that size isn't usually available at RadioShack or regular hardware stores.

http://www.ebay.com/itm/100-PC...e:g:bpMAAOSwwo1Xf~03

 

 

graz posted:
Tfabrizio posted:
phillyreading posted:
Tinplate Art posted:

Do not forget spike protection on the track side of the transformer.

If you use the older post war transformers with newer engines then you must have some kind of protection like a TVS (transient voltage suppressor)unit rated around 32 volts and must be bi-directional.

Lee Fritz

Thanks. I see how to wire a tvs in with a traditional lockon, but how do you wire one in for fastrack?

You could add a crimp on connector to each end of the TVS to allow attachment to the underside tabs of the fastrack - the same connectors used for your terminal wires.

Those exact connectors (.110 crimp connector) are available on Ebay in packages of 100 or so as that size isn't usually available at RadioShack or regular hardware stores.

http://www.ebay.com/itm/100-PC...e:g:bpMAAOSwwo1Xf~03

 

 

You could also just solder it across the center rail and outside rail tabs on the bottom side of the track section where you are connecting your power. I would choose the same outside rail that the power feed connects to.

George

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