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Ray Schofield
Engine Wiper
USA
491 Posts |
 Posted - 06/26/2012 : 08:57:16 AM
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I have just helped a friend who is not electrically very knowledgable install a NCE DCC SYSTEM. A few days after we installed it he called me and said it wouldn't work. When I arrived I noted one of the breakers was burnt, and the system itself was dead. After speaking wijh my friend he said he had turned on the layout, but had not run trains but had just done scenery, The layout is large and is broken into several power districts which are also isolated visually by view blocks. My assumption is somewhere on the layout there was a gap being bridged causing the short that was not noticed and the breaker after several hours over heated and sent the short to the system box causing it to blow. My question is what is to prevent this from happening on any layout?
Thanks |
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simon1966
Fireman
USA
2861 Posts |
Posted - 06/26/2012 : 09:41:37 AM
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Ray, what devices are being used to create the power districts and what was being used as a circuit breaker?
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Ray Schofield
Engine Wiper
USA
491 Posts |
Posted - 06/26/2012 : 09:58:30 AM
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Simon
I am not sure what you mean but the breakers are being used for each power district. I am not sure which breaker they are but were bought from TTX about 8 years ago. They are not the latest, and I know we have changed out our old breakers at the club, but for a sound problem. What I want to know is if these breakers automatically reset and the short is not removed what is to stop them from overheating and failing? Anything? |
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MarkF
Engineer
USA
9272 Posts |
Posted - 06/26/2012 : 10:37:44 AM
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Ray, to my knowledge, they should never overheat to the point of 'burning'. It's hard to tell what might have happened, but keep in mind that the purpose of installing the circuit breakers is to prevent from happening exactly what happened to your friend!
My first question is are you sure the system itself is blown? I would disconnect the system from the layout, power it up and put a meter to the outputs to see if it's working. I am not that familiar with NCC, but most if not all systems have a built in circuit breaker. So if the breaker on the layout went, the system breaker would have tripped. I would start there. It could be as simple as the one breaker that is 'burnt' was a bad breaker. All you might have to do is replace that and he will be back up and running.
In the future, I wouldn't recommend that he power up the layout when he is doing work of that nature. Placing tools, cans, etc., on the track will cause shorts and problems. |
Mark
See my homepage at http://home.comcast.net/~prrndiv/
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Ray Schofield
Engine Wiper
USA
491 Posts |
Posted - 06/26/2012 : 11:05:53 AM
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Mark
I agree with your assessment and yes the system is blown we replaced it and it runs fine. I agree about not powering up the system but he is 86 years old and not as sharp as he once was being a retired dentist. The NCE system does have a built in breaker, but with my little knowledge of electronics a breaker constantly trying to reset must be heating up if the short is not removed isn't it? The Dynatrol system had to be reset and had a buzzer to tell you when there was a short |
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bitlerisvj
Crew Chief
USA
930 Posts |
Posted - 06/26/2012 : 11:45:40 AM
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I have always heard that an old automobile taillight in series with one of the RAIL A or B lines would prevent a burnout. Wire one up in every block. They are pretty cheap insurance and if a short occurs, you get a visual indication immediately. That is, the bulb lights up. I doubt it is meant to replace breakers, but maybe?
Check Alan Gartners web site for more information on this.
http://www.wiringfordcc.com/track.htm
RECOMMENDATION: Use a 1156 Automotive Taillight Bulb to Limit Current to a Track Sub Bus.
Also Joe Fugate has a really cool video demonstration that has me sold on this method.
Regards, Vic Bitleris
quote:
Originally posted by Ray Schofield
Mark
I agree with your assessment and yes the system is blown we replaced it and it runs fine. I agree about not powering up the system but he is 86 years old and not as sharp as he once was being a retired dentist. The NCE system does have a built in breaker, but with my little knowledge of electronics a breaker constantly trying to reset must be heating up if the short is not removed isn't it? The Dynatrol system had to be reset and had a buzzer to tell you when there was a short
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bitlerisvj
Crew Chief
USA
930 Posts |
Posted - 06/26/2012 : 11:54:18 AM
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Here is Joe Fugate's YOUTUBE video that explains the concept really well. It also shows how to wire these up.
Regards, Vic Bitleris
http://www.youtube.com/watch?v=IzrfarW3geQ
quote:
Originally posted by Ray Schofield
Mark
I agree with your assessment and yes the system is blown we replaced it and it runs fine. I agree about not powering up the system but he is 86 years old and not as sharp as he once was being a retired dentist. The NCE system does have a built in breaker, but with my little knowledge of electronics a breaker constantly trying to reset must be heating up if the short is not removed isn't it? The Dynatrol system had to be reset and had a buzzer to tell you when there was a short
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jbvb
Fireman
USA
1865 Posts |
Posted - 06/26/2012 : 12:06:19 PM
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| I'll second Vic's suggestion, but for your 86-year-old friend you might want to simplify a bit: Put an appropriate number of 1156 bulbs in parallel on the output of the booster, and mount them up on the wall or ceiling so their light will be visible when the booster is near it's rated output. |
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nhguy
Fireman
USA
3666 Posts |
Posted - 06/26/2012 : 1:35:18 PM
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quote:
Originally posted by Ray Schofield
I have just helped a friend who is not electrically very knowledgable install a NCE DCC SYSTEM. A few days after we installed it he called me and said it wouldn't work. When I arrived I noted one of the breakers was burnt, and the system itself was dead. After speaking wijh my friend he said he had turned on the layout, but had not run trains but had just done scenery, The layout is large and is broken into several power districts which are also isolated visually by view blocks.
Ray, You said your friend turned on the layout WHILE doing scenery? If he used any liquid like water, alcohol or glue, the whole area was a short. No single circuit breaker or combination of circuit breakers would prevent a short from frying a bunch of electrical components. It would simply bridge them and burn out a circuit breaker like you have found. Never. never, never turn on any system whether it be DC or DCC (especially) when the scenery is wet. Dead short. Bill |
Bill Shanaman
Superintendent, New Haven RR in the 1948 to 1952 era
PMRA President 2013-14, OpSIG Member
NCE User Since 1999
Sugar City, Colorado |
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Ray Schofield
Engine Wiper
USA
491 Posts |
Posted - 06/26/2012 : 3:33:50 PM
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Vic
The light bulb will work, but is also limiting the power to the track significantly. We have used this on our club layout with turnout power routing. Some locos stall (older open frame motors) on the turnouts if the rail isn't touching and only the power through the bulb is available, This would be a serious concern in a power district.
Bill that is an interesting observation, but even raises the spector of him not realizing he maybe putting metal tools on the layout |
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Tommatthews
Fireman
7278 Posts |
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Ray Schofield
Engine Wiper
USA
491 Posts |
Posted - 06/26/2012 : 6:37:06 PM
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| Thanks Tom we used single units, but the same idea. My queation is if you have a short and do not remove it for sometime say several hours does the unit heat up? Most of us recognize we have a short and remove it in minutes. What happens when te short is not removed? |
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MarkF
Engineer
USA
9272 Posts |
Posted - 06/27/2012 : 12:34:39 AM
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quote:
Originally posted by Ray Schofield
Thanks Tom we used single units, but the same idea. My queation is if you have a short and do not remove it for sometime say several hours does the unit heat up? Most of us recognize we have a short and remove it in minutes. What happens when te short is not removed?
Ray, in theory (I repeat - in theory), the circuit breaker interupts current flowing to that area protected by the circuit breaker. Our DCC circuit breakers have a built in self-resetting circuit, which means after a specified period of time, the breaker will attempt to reset itselt. If the short is still there, it trips again. This cycle repeats itself until the short is resolved.
Now, does that mean that the breaker will not heat up? Not neccessarily! I have never seen this happen, but I guess it could. Perhaps someone here with a little more knowledge on electronics could chime in and provide a better answer on that one.
As for using 1156 bulbs for circuit breakers, yes they will work, however there are a few things to remember. The bulb by itself is NOT a circuit breaker. The theory behind this is that it provides a route for the current to pass and the light provides some resistance. However, what is really happening is that the short is creating a circuit that lights the bulb! Add to this that the lighting of a bulb takes time. We are talking miliseconds here, but depending on the current, those few miliseconds can do a lot of damage to a decoder or anything else in the path of the current. In addition, most boosters today have built in circuit breakers that will trip a lot faster than the bulb, totally defeating the purpose of having circuit breakers.
So while the 1156 bulb does work, given the choice, I would stick with a good brand of DCC circuit breaker. |
Mark
See my homepage at http://home.comcast.net/~prrndiv/
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BNSF Fan
New Hire
47 Posts |
Posted - 06/27/2012 : 08:34:12 AM
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Mark,
"Live is like a roll of toilet paper. The further into it you get, the faster it goes!"
Shouldn't that be "Life" rather than "Live".
Respectfully,
BNSF Fan |
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Tommatthews
Fireman
7278 Posts |
Posted - 06/27/2012 : 09:36:01 AM
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Ray,
Sorry I can't answer your question. I`"try not" to power up my DCC unit unless I am running trains and shut it down when finished.
Some guys wire the wall plugs to a light switch so when they enter / leave the train room they turn all the power on / off. |
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MarkF
Engineer
USA
9272 Posts |
Posted - 06/27/2012 : 09:48:16 AM
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quote:
Originally posted by BNSF Fan
Mark,
"Live is like a roll of toilet paper. The further into it you get, the faster it goes!"
Shouldn't that be "Life" rather than "Live".
Respectfully,
BNSF Fan
Do you know how long I've had that quote, and you are the first one to comment on that! [:-bigeyes] So noted and fixed!  |
Mark
See my homepage at http://home.comcast.net/~prrndiv/
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Topic |
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DCC circuit breakers
