Automotive breaker. Buss brand. 32VDC, 250 VAC., Manual reset breaker. Breaker will not trip. I put one breaker in line on the D handle of my ZW Iam getting 20.8 volts out of this ZW . I use this ZW for my TMCC. I made a direct short to test , breaker will not trip, I held the short for 5 sec. Iam doing some thing wrong, or do I have a bad breaker. I will continue to use 32V, 15 amp quick blow fuses for now. the reason I want to use a breaker is little hands dont always set cars on the track correct the first time. Yesterday I went through 7 fuses. Thanks for all your help.
By the way love TMCC. I ordered 4 upgrade kits already. 5 and 3 year old got the hang of it almost to quick, already ordered a second Controller for them to use.
As I read the data sheet, I think it should have tripped in 5 seconds at somewhere between 27 and 66 amperes (180 and 440 percent of rated current). You probably can’t get a whole lot more than 30 amperes out of a short-circuited ZW; so 5 seconds may not have been long enough. If your wiring is not heavy, that could reduce the current also.
A failed circuit breaker is of course a possibility.
I ordered one of the new Power Sheild Breakers from DCC Specialties. Hopefully will have it to try out this weekend. It’s designed to accept 12 gauge wires and offers 4 choices as far as ratings depending on how you wire it. Breaker resets automatically in 2 seconds or manually. My transformer has very fast acting 12 amp breakers. It has a 12 amp setting so I’m curious to see which trips first. Some nights I seem to change a lot of fuses as I have these in each channel of my TIU. Working on adding Kadee’s to some passenger cars and derailments can be plentiful when testing cars.
Go to Scotts Odds and Ends and order you a fast acting breaker box. I use 12V 15amp automotive breakers [recommended by Bob Nelson] in all of my Post War ZWs. I then short them as a test. Works great. I then have a fast acting 15 amp breaker box I built [from OGR Backshop video] between my ZW’s and my TIU. The TIU feeds the track sections [all four are programed fixed voltage]. Running Atlas diesels slowly through 072 Realtrax switches or even my new Lionel SD40-2, will trip them immediately. If I were doing it all over, I’d probably go to Scotts for a quick buy.
As the posts above note, breakers/fuses are vital for protecting your transformers.
But to protect the fragile motor wiring and circuit board solder traces in your engines from being zapped by a spike, transient voltage suppressors [TVS]are the key. Bob Nelson [lionelsoni] Cam and others have several times posted specs and sources [Mouser,Newark Electronics,etc.]for the relatively iinexpensive TVS which is simple to connect between the Railpower conductors that feed from the transformer-to-track. Installlation of TVSs within the engines itself is more difficult but doable.
Chief’s breakers are external----a row of 4 housed in a separate plastic box ,not inside the ZW housing. One source of breakers that OGR’S Jim Barrett recommended was from Newark Electronics. I am sure that Mouser and other Electronic Houses have similar breakers. The ones I used are Potter-Brumfield 10 amp breakers from Newark. I have since replaced the breaker box with an old four position Autolite fuse block containing 10 amp fast blow fusex.
What A&Y says is right. Circuit breakers and fuses are for protecting the power source, not the load. For this, you don’t need anything that reacts fast to a brief overload, because such an overload doesn’t damage your wiring or transformer. The fuse’s or circuit breaker’s response to the overcurrent should mimic the behavior of the source, which can stand an overload in much the same way as a locomotive’s traction motor–no harm is done until the thing gets hot; and that doesn’t happen immediately.
Fuses and fast circuit breakers help but do not directly protect you from voltage spikes. They just get the circuit open to reduce the number of spikes that can get through when a fault occurs. A TVS, as A&Y says, stops all the spikes and makes a fast circuit breaker or fuse unnecessary, which is good, because their frequent tripping or blowing can be a nuisance.
I have ATC-type automatic-resetting automotive circuit breakers installed in both the type-Z transformers that I use, in series with the individual outputs, not the return. There’s plenty of room to put them inside that box.
This is what I did withmy Z’s and K’s. Bob is the one that helped me do it with his advice. Now I also have the fast acting breakers in a box I built. Got everthing from Radio Shack except the beakers. Had to order them. Built the box [porject box] with binder posts and banana plugs. They trip fast. Scotts will save time. I enjoyed building my own. A&Y [Dewey Trogdon] and Lionelsoni [Bob Nelson] know their electronics. Great helpers.
Those look okay. Just about any automotive circuit breaker that you can find in an auto parts store will be fine. Interrupting DC is much harder on the breaker than interrupting AC; so a 12-volt DC rating will be just fine for the AC voltages that we use. Select the current rating according to what the transformer can put out and the wires can carry: 15 amperes (or less if you want) for a Z or ZW with AWG 14 or heavier wire.
I ordered the TVS’s from Mouser Electronics and have them at my house already. I have a question about installing them, which side gets hooked up to the positive and which one to the negative?
If you got the right type, it doesn’t matter–they are symmetrical. The Vishay number looks something like “1.5KE36CA”. The “C” means bidirectional. Without it, they won’t work on an AC circuit (which has no consistently positive nor negative polarity).
Bob, I did a search on the number you listed at Mouser and got a whole list of matches. Am I correct in assuming that high surge current is the best criteria to use as long as the operating voltage is high enough? I want to add these to my layout, but have been puting it off.
The hits I get at Mouser for 1.5KE36CA (for example) are all for the same part, but from different manufacturers and for different packaging, that is, reels of thousands of parts for high-volume production versus individual devices. They should all work. Vishay originated that part; so I would probably buy theirs.
