DCC Circuit Breakers...

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Are they very important to have? if so how can you consider how many you might need for your layout? I just finished the benchwork on my new layout and im trying to soak up as much info as possible from here and different sites on the web before i start the track laying and wiring.


New Member
When I converted to DCC about a 18 months ago I installed three circuit breakers. One in each of my power districts, aka blocks.
I turned on all block switches and have run merrily ever since.

While circuit breakers are not required in DCC, as the DCC hardware contains its own fast acting breaker, having a breaker with a lesser amperage in each block eliminates having the entire DCC system shut down when there is a short.

Only the block in which the short is located will shut down. This requires the circuit block breaker to trigger before the system circuit breaker.

Each of my breakers are less then 4 amps while my Lenz 100 DCC system is rated at 5 amps.

So while not required, I do find the multiple breakers helpful in locating shorts and not shutting down the entire layout.

I use the breakers from Tony's Train Exchange.


Fun Lover
Check out Joe Fugate's site for a tutorial on DCC power districts. He uses auto-lights that act as quasi circuit breakers. They alert the user to a short, protecting it without cutting power, but allow everyone else to contiue running. And the cost is less than $2 ea, compared to what ever the price you can get for a dedicated circuit breaker.

In my mind, it is the way to go, both from an efficiency point of view as well as a cost POV.

I couldn't find the info on Joe's site, but I know it is there. You can see it here:


providing the address doesn't change with the new system.
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i heard about the auto ligt bulbs being used but wasnt entirly sure. ill look into it thnx

ok i saw the video one thign iw as confused about do you nneed a power booster in each district to get it too work the corect way? or can it work with just one booster and still seperate it into districts and still work correctly?
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ok sounds like a good way to go with it cheaper then buying an actual circuit breaker witch is very expensive. thnx for the help.


New Member
The problems with the light bulb method is:

1) It does not shut down the power to the shorted block/district. So it continues to draw current. And you need to break the blocks into small sections if you are going to have multiple engines in one block. Multiple engines may draw enough current to affect their performance as the bulb acts as a resistor.

2). It requires more wiring. If time is important to you this should not be ignored. If you use 5 or 6 bulbs where 1 circuit breaker would do the job the cost difference narrows.

If you buy the 4 dictrict breaker you really get two 2 circuit breakers on one board that can be literlly broken into two boards if you desire.

The bulb method is a good alternate to circuit breakers but they are only limiting resistors , not circuit breakers.

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