New guy, 1st question about PS2 & 1033 transformer

[Anonymous]

Fuse and surgesuppressor in the outlet strip are there to provide surge protection from power line spikes and to protect the house from damage from a short. The stuff on the low voltage side is supposed to protect the transformer/power supply and/or the stuff attached to it. The delicate electronics inside the loco is where you need the surge suppression but none of the manufacturers seem to be interested in doing this. Plaing the surge suppressor on the transformer's outputs beats a poke in the eye with a sharp stick but it is basically providing protection from a spike originating in the power supply. It may or may not protect from a spike coming from something else on the layout.

[lionelsoni]

Yes. The transformer secondary winding has some inductance because the primary and secondary windings do not encircle exactly the same flux lines. When the secondary circuit is opened, the collapse of that flux induces a voltage spike that is not seen on the primary.

[Jamesh1083]

Thanks, Chuck & Bob, for your quick inputs. Talking this issue over with some colleagues here at work and a question was raised that I couldn't answer. Why wouldn't a power strip with surge protection work just as well, if you plug the transformer into the surge protector? I'm guessing there's going to be some differences between the 120VAC from the outlet and the voltages induced in the transfomer between the primary and secondary?

[lionelsoni]

If I'm not mistaken, they're designed to fail shorted. So you would get no voltage to the track, and the transformer's circuit breaker would trip (or a fuse would blow, if you use one). Transxorbs and MOVs do pretty much the same thing, just with different technology.

[Anonymous]

You probably won't be able to tell by physical inspection. Follow this link to get to more info than you ever wanted to know about spike protection for toy trains:

http://www.hirailers.com/technical.htm

There is a wealth of other useful information there too!

[Jamesh1083]

Guys, thanks for the great tips. I understand what you're saying in terms of the difference between the fused protection and the voltage supression. I have a question about the voltage suppressor. How would you know if the voltage suppressor stops working? Is there a physical burning of the component to let you know? Or would you have to check it with a meter across the leads? Also, is this Tranzorb similar to a Metal Oxide Varistor? Thanks, I'm picking up my engine tomorrow and would like to have everything ready beforehand.

[jlrocks]

lionelsoni---Thanks for the info and the links. You guys are a wealth of info. I appreciate it.

[lionelsoni]

It's like a zener diode or two of them in series. It clamps the voltage at the value specified, in one direction or both, respectively. Here is a link to a posting with some sources:

http://www.trains.com/community/forum/topic.asp?page=-1&TOPIC_ID=53851&REPLY_ID=599407#599407

[jlrocks]

I am new to all of this electronics stuff so bear with me. What is a TVS-Transzorb and where would I find one?

[lionelsoni]

When you consider that a short circuit results in zero track voltage, it is hard to see why a fuse or circuit breaker would have anything to do with protecting a locomotive, rather than the transformer. However, it is likely that a short circuit will begin with numerous and rapid repeated shortings and openings across the track. The stray inductance of the transformer secondary would be likely during that time to put out spikes much higher than the normal voltage, which could then damage the electronics in modern locomotives. The problem is that any damage is done by high voltage, not high current. (Traditional locomotives are pretty much bulletproof.)

A fast-acting fuse or circuit breaker can help by opening the circuit before the fatal spike occurs; but it would be more direct to use a transient voltage suppressor (TVS), like a Transzorb, across the outputs. It should be rated at a little more than 140 percent of the highest transformer RMS output voltage.

This is not to say that you shouldn't add fuses or circuit breakers, to protect the transformer and wiring.

[Jamesh1083]

Thanks, Guys. I had been wondering about the recommended voltage for the fuse. I'm a manufacturing technician and have access to in-line fuse holders and different sized fuses. I thought I'd seen 10A recommended in the past. Do you think the 5A fuse will handle the engines plus accessories and lighted cars? I've got the 394 Rotating Beacon, 252 Crossing Gate, 154 Crossing Flasher, as well as some lighted cars.

[willpick]

I I'll second the fuse reccomendation. ANY modern (1990-present) that has electronic sounds/speed control/etc. MUST be protected with at least an appropriatly sized fuse. Your GP30 will draw less than 2 amps at full speed, the 614 switcher (assuming it has a pulmore motor) will draw 3 or more amps.

So I'd suggest using a 5 amp 32V fuse maximum . You can buy an inline fuse holder and the 5A fuses at any auto parts store-- I don't reccomend Radio Shack anymore, unless you are desparate[:)]. And Welcome back to the hobby!

[spankybird]

You should be fine. I would suggest adding a fast acting fuse between your transformer and the the track. This would protect your electronics in the engine in case of a derailment.

[Jamesh1083]

Hi, I've been getting back into O-gauge trains after having my old Lionel stuff stored for me for many years. I've got an old 1862 General set and an Alaska 614 switcher. My birthday is this Friday and I've been shopping for a new engine, settling on an MTH GP-30 with PS2. I'm using a Lionel 1033 transformer. Aside from purchasing the sound activation button so I can ring the bell, since the 1033 only has a whistle button (a position on the directional lever) does anyone have an opinion or know of any complications I might run into by running the PS2 engine with the 1033 transformer? I'll be running it in conventional mode on Lionel Fastrack. I'm still researching TMCC and DCS, leaning toward DCS, but don't have either yet.


P.S. This is a fantastic forum and I've learned a lot from reading the topics posted here.