Overloaded ZW or bad breaker

Many times the breakers do go bad with age.  A key would be if the transformer got warm at all.  If you're really running at the limit of around 15 amps for an extended period, the case will be fairly warm.  Not hot mind you, but plenty warm.

An automotive cartridge breaker is a good replacement and fits right in, I use 15A ones for the ZW and a 10A one for the KW.

Thanks.

The ZW top was warm, but not hot at all (and I've felt hot ZWs in the past). I'll look into the breaker type you mentioned and also see about getting a cheap modern meter that can read AC amps.

I find this Harbor Freight Clamp-On Meter to be very handy around the trains.  It's got better accuracy than I would expect as well.  It's great to be able to measure the current without breaking a wire.  Hard to beat for the price.

John,

Does that meter actually work?

I bought a slightly different clamp meter from HarborFreight about 2 years ago.

It was a dud. It will not give me any AC amp readings.

Not only does it work, but when checked against my Fluke bench meter, it was better than 2% on current and voltage readings.  I use it regularly, and I'm very happy with it.

FWIW, I did buy a different meter from HF for the temperature feature, I had to exchange it to get a working one.

My experience with them is typically with this kind of item, that once you get a working one, they are pretty decent.

So I bought a 15A auto-breaker and put it in. Works like a charm. Had the trains going about four hours today and it didn't trip. Got plenty warm though.

It does work as I did a short to test it. I know that's really not what should be done but I don't have the parts to simulate the necessary load.

As for the meter I looked at Radio Shack and Home Depot. Every one I found that read AC amps was at least $70. There's a Harbor Freight up in Glen Burnie (about 30 miles from me). I'll have to check that out when I'm up that way some time.

Thanks again for the advice.

Harbor Freight does mail-order.   Clamp-On Meter

I'm sure it'll be less than the gas to drive up there.

You can get a Milwaukee multi meter for around 100 bucks good quality.Has an inductive amprobe leads that will measure ac dc voltage, resistance and continuity.I don't know how anyone building sizable layouts could possibly be without one.

Is this the type of breaker that was used??

You can buy a perfectly serviceable clamp-on meter from Harbor Freight for $12, I've used one her for a year.  When checked against my bench Fluke meter, it's within 2% measurement accuracy, more than sufficient for model train layouts.  There's no reason to spend $100 for a meter unless you have a more demanding application for it.

or a lot of money

John is right. I have the same clamp on meter and it has worked fine for a couple of years and it's accuracy is similar to John's when tested for voltage against my Fluke meter. I have no meters that measure current but the values seem to be good. I also have several of the free ones Harbor Freight was giving away and they also work fine in the train room.

Ron

When I retired I was given a Fluke multi meter w/clamp on & True RMS.  Tried the Harbor Freight & the accuracy wasn't there but not bad.  If I would not had the good Fluke Harbor Freight volt amp meter would have been fine.

Ken