ZW-C aka 6-32930: Do I need extra breakers to protect the engines?

No.  The circuit breakers and overload protection of the ZW and bricks are there to protect the transformer and wiring, not the trains or their circuitry.

The damage to the electronics will be done before the breakers trip.  This could instantaneous  or cumulative.

To minimize this type of damage, you want transient voltage suppression/protection.

Wow thanks, nice link.

Is that TVS diodode something I can pick up at Radio Shack or other electronics store?  Does Lionel or other sell this the LHS?

Do any transformers fully protect engines?

Here are links to numerous discussions that will help guide you and assist with sourcing.

There really isn't anything inherent in the design or function of an AC power supply that would provide such protection.

There are devices that have surge and/or transient protection to be used with transformers.  QSI and K-Line made some, the Lionel Direct Connect lockon has protection, the MTH TIU has TVS protection.

Thanks I'll check out the links.  Lot of good info.

Just curious can a fuse between the track and the transformer suffice?

No.  A circuit breaker or fuse is there to protect the transformer and wiring, not the trains or their circuitry.

The damage to the electronics will be done before any breakers trip and long before a fuse blows.  The damage to electronic circuits can instantaneous or cumulative.

 The ZW-C has electronic breakers which are very fast and will avoid the welding that other mechanical breakers allow. So you are good that way and if you get a TVS to put across the track center and outside rail that will go a long way toward protecting the engines.

I'm not sure the protection of the ZW-C is sufficient, I'd have to come down with Rob on this point.

This is what they say in the manual.

To protect the transformer from overheating and damage due to short circuits, the ZW Controller-PowerHouse Power Supply system is equipped with built-in automatic circuit breakers. To prevent over-current on engine start-up, the voltage is reduced when the current exceeds 10.5 Amps. Using this method, a single channel of the ZW Controller is capable of running a lash-up of about six Lionel locomotives, depending on the condition of the units. If the current does not drop below 10.5 Amps within three seconds, a short circuit is assumed and that channel of the ZW Controller will drop to zero volts and the red light will begin flashing. After six seconds, the channel will attempt to resume normal voltage. If the short condition is still present, the channel will trip again. If the channel trips more than six times in a row, it will remain at zero volts, and the red light will continue to flash.

Also, later on the same page.

It is important to understand that the purpose of the circuit breaker is to protect the transformer itself. It operates only if the transformer is overloaded.

My ZW-C trips out instantly. I've never noticed it trying to make up it's mind. 

For short circuits or overloads, yes.  For surges and spikes, it is way too slow.  The damage, whether instant or cumulative, is already done by the time a circuit breaker trips.

I have installed TVS for that...but not sure I've ever had a surge or spike. At least in the years before the TVS.

I will definitely install the tvs, thanks.

My power is plugged into a power strip/surge protector, still too slow?

Thanks I'm learning.

You can do better with one of these for each track circuit...

http://amhobby.com/products/te...owershield_x_ac.html

or here...

http://www.traintekllc.com/Pow...gement/products/316/

from these dealers too...

http://www.dccspecialties.com/dealers/index.htm

None of those products provide the needed protection.

Even Slower.

The ZW-C 32930 uses bricks to supply power.  The bricks are protected and will trip if there's any short on the track that they'er connected to.  There's also circuit protection inside the ZW controller.

I have four blocks powered by the modern ZW and that's all I have ever used to protect against shorts.  Going on over ten years now using every Lionel PRR engine made, from the 1947 2332 GG1 to the latest PRR Vision Centipedes.

For one reason or another, almost every operating session, always my fault, I trip a circuit.  I've never ever fried anything.  Power is cut instantly.  I solve the problem, slap myself on the forehead, reset the brick circuit breaker and I'm good to go.

I really don't believe I'm missing anything.

Nowhere is it mentioned that there is clamping protection from transient voltage spikes and surges.

This is a very different concern from short circuits or overloads, the damage is often not immediately noticeable because many electronic devices are designed to take some abuse, but will fail after an accumulation of abuse.  Electrical failures are always mechanical in nature.

Oh ok, all about the spike and transient voltage issue...

That is covered by this statement which is not as complete as it could be...

"Over Voltage Protection           If there is an over voltage on the track caused by an AC System failure or other power inputs the PSX will shut down and protect your locomotives."

That would be the Locomotive protection that is not provided in the ZW-C then.

There IS a surface mount TVS on the very input of this protection circuit for transients, spikes, etc, but I have to say it is somewhat low in clamping voltage. I removed it and put the higher clamping voltage TVS that was suggested in earlier threads. I did this because I managed to short one of them with the CW-80 and why I removed them.

But as I think about it, I would leave it installed until, and if ever, it clamped too soon because it is more protective that the Forum recommended TVS units.

That was a good idea, because the CW will put out almost 30 volts, I think, as observed on a scope.

Check out the article on surge protection at this website

http://www.hirailers.org/

Go to the tech bulletin section and read the paper on surge protection. It is a very informative article.

You can just install TVS's across both input and outputs from your transformers. Cost is less than $.25 each or you could build the device in the paper.

Some recommend installing the TVS's in the engines themselves which is a good idea however this method will not protect any of your accessories like Lionel TPC's, or the control accessories like Lionel Accessory Switch controllers etc.

Also if you only have TVS's installed in engines and not protecting the layout if someone comes to your house to run their trains and they have a derailment they won't be protected. So, you could do both.

I have had this exact experience on five different layouts that I am or have been intimately involved with that are using the 6-32930 ZW controller.  The brick"s breakers are the fasted thing I have ever seen.  In ten years of operation, I do not think the breaker in the ZW controller has ever tripped.  It is always the brick that trips.

It is hard to believe that the brick's performance could be improved upon.

Happy railroading,

Don

There's nothing to preclude you installing TVS protection on other places if you put them in the locomotives.  The TVS is most effective closest to the device you're trying to protect.  If that's the locomotive, then across the pickups are the ideal place.  If you want to protect your TPC or accessory controller, put one across that device.

I think I pretty much said that. You must either don't have life or just need to have the last say. Getting a little tiresome.

Thanks guys as usual for your superior knowledge/experience on this stuff.

Also thanks Dewey for the images as this amateur will gladly use them.