Everything on model trains, model railroads, model railways, locomotives, model train layouts, scenery, wiring, DCC and more. Enjoy the world's best hobby... model railroading!
Wiring For Post War O gauge layout
Scott posted this question in the hope of getting some help:
“I have a 4X8 Postwar O gauge layout with a ZW transformer. Nothing extravagant there is an inner and outer loop with 2 O22 switches. I have a few accessories, nothing fancy. The problem is the layout will shut down when running after a while, the red light on the ZW will come on and after 5 seconds or so it will re-set. I’ve checked the cars one by one for a short. I’ve shut down the accessories but it still stops and then re-sets. It’s almost like it overheats? I have a bus line and feeders. Any ideas that I can troubleshoot would be appreciated. This is driving me crazy 🙂 Thanks for the help!”
Please add your suggestions to assist Scott below.
SUBMIT YOUR QUESTION
It shouldn’t be a short, that doesn’t usually happen “after a while” unless it’s happens every time you do a particular operation at one part of the track or activate an accessory.
Are there air holes into the transformer that maybe you could use an aerosol can to blow out? (I’m thinking of the cans you get in a computer store to blow the dust out of a computer.)
Any electrical issues must be addressed by isolating each unit….setup a workbench area and start with using the ZW and one locomotive then accessory….and so on….also look for any “modifications “ or repairs that a previous owner may have made, ie…led light that may not be installed correctly…be patient and have fun.
It certainly sounds like a fault in the transformer. Have you tried disconnecting it from everything and then run it to see if the trouble then occurs?
Perhaps you could fo some experiments for us. Start a spreadsheet .
Can you measure current?
Time start,
room temperature,
Locomotive
# of cars
Accessories
Current
Time of failure
How hot does the transformer feel
Next test: locomotive only with accessories
Next test. Locomotive only
Next test accessories only
Two possibilities, a faulty overload protection on the transformer or the layout drawing too much power, a faulty loco or something in the wiring or trackwork. You could probably start with a basic ammeter and go from there, component by component till the fault is located.
If you have an ammeter that can measure several amps (many testers can’t handle more than a fraction of an amp), you could wire it in series and see if and when you have excessive current draws. Hopefully not a failing ZW. 🙂 I suppose another possibility is a pair of feeders is reversed, which normally would give a dead short, but if the track connections are badly oxidized it might not, or if one block of track is isolated (fiber pins rather than steel) and polarity reversed it would short out only as wheels passed over. You could try disconnecting all but 1 feeder & see what happens. Good luck
Hey thanks for all the feedback! I’m going to start working my way through a number of these suggestions and hopefully land on the problem. I better get to work!
I had a problem with my postwar KW the breakers in those things get tired and they keep tripping out . Iwould check your breaker and possibly get that replaced I wish I would’ve did it myself because I’m pretty handy but at the time I paid somebody I’m thinking it is your breaker in the transformer just getting tired beach check by putting a load on it. I found out about this from an old 60s 70s Train Repair guy. Last time I looked handful of years ago those breakers aren’t that much money might not even be worth the hassle of bench
testing .
I agree with John’s message dated November 5th about the breakers. I had a similar problem and found it to be a breaker issue.
Thanks guys, I Will be taking a look at the breakers.
frist take everything off the tracks and apply power and see what happened if the red light is off put one car back at a time and repeat the same until all cars are back on the track or try another transformer and see what happens I have a zw on my layout and it runs fine.