Why is it a good idea to use the 5 amp breaker on a postwar transformer? If its not used what are the risks?
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Postwar transformers' breakers are really slow and are there only to protect the transformer itself. If you're using a postwar Transformer, then using a fast acting breaker or fuse will help prevent welding the wheels to the rails or melted wire insulation (in the trains or layout) in the event of a prolonged derailment. As for the current rating you choose, that's another question that requires more detail from the user.
Most newer transformers have better (than postwar) breakers already in them from the factory. Instant breakers are what I prefer to add.
https://ogrforum.com/topic/air...al-mechanisms?page=1
If installed correctly, TVS diodes help protect sensitive electronics in command control equipped trains.
@Bob is cool! posted:Why is it a good idea to use the 5 amp breaker on a postwar transformer? If its not used what are the risks?
One simple concept- FAFO - the "Finding Out" part is what you are trying to avoid.
https://ogrforum.com/topic/fire-in-the-hole
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I never realized how much they are needed until I added them to my layout (KW power). I can recall one time when the breaker in the transformer tripped before I added the new circuit breakers.
I used 8 amp quick trips.
If you are running modern locos with boards they are mandatory. Search the Forum- lot's of discussions.
@RSJB18 posted:If you are running modern locos with boards they are mandatory. Search the Forum- lot's of discussions.
Breakers optional. Transient Voltage Suppression mandatory.
Sounds like i'm ok with post war locos But I do have modern locos I run with a MRC Dual Power. Should I use a 5 amp on that?
It's optional, depends on whether you want additional insurance, and on which MRC Dual Power you have. There are several models with different output capabilities.
Which MRC Dual Power model do you have?
AH601 Pure Power Dual
The stock breakers in the AH601 are thermal. That means that they take time to heat up when there's a short circuit condition. The instant breakers I linked earlier trip in milliseconds. If you go with one of the instant breakers, either a 7.5 or 10 Amp would be my choice for the AH601. The 5 Amp would likely buzz with a heavy load.
Also, seriously consider adding TVS diodes for your modern locos if you haven't already.
What about MTH Z4000 Don't know if there's differential models of it
@Bob is cool! posted:What about MTH Z4000 Don't know if there's differential models of it
Maybe, I'm less familiar with the Z4000. I'm going to leave that answer to someone else. Maybe @Vernon Barry has an opinion?
Yes,Please help me I've lost several post war trans also I don't know what TVS diodes are. I see mentioned of them on rebuilt transformers sites
The Z4000 can output 12A for several seconds before any form of shutdown happens.
If the picture I posted wasn't enough of a reason to get smarter and use a breaker- you kind of deserve what happens next. You've been told- stop coming up with reasons to avoid it.
Basically, Bob- You, yes YOU are the reason you need a breaker.
Doesn't matter the transformer, it matters that YOU will be running trains, mistakes happen, derailments happen, and I could cite all day long the number of things that won't take 12A shorted without burning up.
GET THE HINT.
Thanks so much for all the input I haven;t been purposely avoiding it Just ignorance on my part. I'm glad to get all the good reasons to get my butt in gear with it I'll work on it asap
@Vernon Barry posted:One simple concept- FAFO - the "Finding Out" part is what you are trying to avoid.
https://ogrforum.com/topic/fire-in-the-hole
FAFO could well result in FUBAR.
A 5 amp circuit breaker or 5 amp fuse should be good for most power demands. Just as a reference the MTH z1000 controller is rated for 6 amps and the power brick circuit breaker is quite instant when a derailment occurs. Remember the old Lionel zw or kw transformers were meant to operate with the trains of the post war era not modern trains with modern electronics.
At the end of the day, this is just another reason for a good fast acting circuit breaker on the typical layout.
Every time topic comes up:
Risk assessment 101
- What does even one single damaging event cost in repair?
- What is the highest dollar amount train or item that could be damaged?
- What is the chance of of an event or multiple events- per day, per week, per year?
What is the cost of prevention (cost of the breakers or fuses and wiring- maybe TVS diodes)? Pennies on the dollar compared to even one major event.
Bottom line, if a breaker or fuse prevents even one event from causing serious damage, it's paid for itself.
Call me crazy, but I use 3amp quick-blow, quick reset fuses on all of my transformers and DCS Remote Commander, and TVS's in ALL my MTH loco's, be them PS1, PS2 (3V&5V), and PS3.
I'd rather be resetting the 3amp fuse time and again than shelling out for new circuit boards (if available).
I can run my early Buco open framed armature loco's through my early Buco transformer (0-22VAC) and I have never had the 3amp fuse "pop" under load. Only if the loco derails (as they sometimes do) does the 3amp fuse "pop", and I have to wait a couple of seconds to "reset" it.
Cannot emphasize enough the words/advice of Vernon.......get quick acting external fuses on your layout!!!!
Peter.......Buco Australia.
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this conversation has been around for quite a while. I would definitely recommend a PS-X Ac. It is incredibly fast, can be set to go off at a range of amps and is a very simple install.
Marty
The issue with using PSX-ACs is they are designed for Command Control trains. They require 10 volts track power to operate. Not ideal IMO if also running conventional locomotives.
