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Can’t understand system short

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Can’t understand system short
Posted by gdelmoro on Thursday, February 22, 2018 12:11 PM

Hi all,

I give up so I’m hoping one or more of you can help.

I have an NCE Power Pro system with radio.  The control box is connected to a terminal strip and then to three NBE Circuit Breakers which segrate the 2 mainlines (Main) from the Sorting yard and Ferry Yard.

If I disconnect the wires from the terminal block feeding the two yards and check track voltage with my rampmeter I get 14.3 ONLY on the Main the other two districts are dead.  

The two yards are gapped and have no connection to the Main lines. If i do the same with each district I get the same the connected one reads track voltage and the other two are dead.  All sounds good.

When I connect all the breakers and all the districts are live placing a quarter on the Main shorts out all three breakers.

Any ideas?

Gary

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Posted by selector on Thursday, February 22, 2018 2:00 PM

Your terminal block does not separate the three 'districts'...it merely feeds all of them at the same time.  Your experiment with removing wires proves this.  The short is the command unit sensing a short via its routing, which includes the terminal block.  So, it dutifully shuts off power to the rails and squawks.

AND----your breakers appear, if they function well, to tolerate more of a short, or are delayed sufficiently in responding to one, that your command unit beats them to the punch and stops the short itself.

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Posted by MisterBeasley on Thursday, February 22, 2018 2:03 PM

Are you sure you're shorting out "all three breakers?"  Could it be that the quarter test is actually shorting out the system breaker which feeds all 3?

It takes an iron man to play with a toy iron horse. 

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Posted by BigDaddy on Thursday, February 22, 2018 2:39 PM

I wonder what the quarter test would do on the other 2 districts?

The PSX circuit breakers daisy chain to other PSX breakers, but I'm not sure that is electrically any different than the terminal strip.  If the main circuit breaker is defective, it could trip the other two and the command station.

Henry

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Posted by DigitalGriffin on Thursday, February 22, 2018 4:02 PM

I would agree with selector.  Disconnect the terminal block  from the breakers and layout and turn back on the power and see what happens.

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

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Posted by gdelmoro on Thursday, February 22, 2018 4:13 PM

If i disconnect the terminal block, how do I feed the three breakers?

I have the EB1’s set to 3.5 amps.

When I tried to short the ferry yard district the quafter buzzed on the tracks and the breaker LED began to blink it didn’t shut.

Gary

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Posted by gdelmoro on Thursday, February 22, 2018 4:16 PM

selector

Your terminal block does not separate the three 'districts'...it merely feeds all of them at the same time.  Your experiment with removing wires proves this.  The short is the command unit sensing a short via its routing, which includes the terminal block.  So, it dutifully shuts off power to the rails and squawks.

AND----your breakers appear, if they function well, to tolerate more of a short, or are delayed sufficiently in responding to one, that your command unit beats them to the punch and stops the short itself.

 

So what is the correct way to send power to the breakers?

Gary

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Posted by gmpullman on Thursday, February 22, 2018 4:49 PM

gdelmoro
then to three NBE Circuit Breakers

It took me a while to find NBE circuit breakers. I had to sort through Members of the British Empire appointees first.

Then I thought you might be refering to the EB-1 circuit breaker.

Have you read this?

https://ncedcc.zendesk.com/hc/en-us/articles/201400305-EB1-Circuit-Breaker

I agree with others that your command station is reacting before your EB1 and shuts down the command station.

I have a similar setup although using PSX breakers and Digitrax boosters and command station. I have the trip time set on the PSX breakers set to the minimum trip time.

There are other hints here:

https://sites.google.com/site/markgurries/home/nce-info/nce-accessories/nce-dcc-circuit-breakers/eb1-info

Hope that helps, Ed

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Posted by gregc on Thursday, February 22, 2018 5:12 PM

assume things were fine until something was recently changed?

what was changed?

greg - Philadelphia & Reading / Reading

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Posted by rrinker on Thursday, February 22, 2018 5:19 PM

 Default response time on the EB-1 is 16ms which is the fastest. Yooou can only slow it down, which won't help. If there's a way to adjust the reponse speed of the PH-Pro, it's not in the manual. 

 You sure you have the jumper on the A position for 3.5 amps and not C which is 6 amps? Try taking the jumpers off each one which will set it to 2.5 amps, no possible way to have that messed up, and try the quarter test again.

 If it still trips the system instead of the breaker, you must have some feeders cross connected to the different districts, or the gaps are bridged.

 What about each of the other sections, even one at a time. If just Ferry Yard is connected, does it trip the breaker with a quarter in the Ferry yard trackage? Then while just Ferry is connected, short the track on the main, or in the other yard. Nothing should happen because it all should be dead. The disconnect Ferry and try JUST the other yard. Same thing.

 If at any point, if a quarter in a district that is not connected causes either the breaker or the system to trip - you've got something connecting the two, either a wire in the wrong place or missing gap. No other way a short in a section that has no power bus connected could short out another.

 Looking at the picture, I see something suspicious already. I see a pair of wires comming from the track terminals to the terminal block, which then splits off to feed each EB-1. That's fine, all wired in parallel, they aren;t downstream of one another, that's the correct way to wire them. But i ALSO see another pair of wires coming from the command station and going back up alongside the right hand EB-1 and off to the layout somewhere. Where's that go? A short across those wires will shut the system off and none of the EB-1s will trip. What do those wires connect to?

                                   --Randy

 


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Posted by gdelmoro on Thursday, February 22, 2018 5:28 PM

gmpullman

 

 
gdelmoro
then to three NBE Circuit Breakers

 

It took me a while to find NBE circuit breakers. I had to sort through Members of the British Empire appointees first.

Then I thought you might be refering to the EB-1 circuit breaker.

Have you read this?

https://ncedcc.zendesk.com/hc/en-us/articles/201400305-EB1-Circuit-Breaker

I agree with others that your command station is reacting before your EB1 and shuts down the command station.

I have a similar setup although using PSX breakers and Digitrax boosters and command station. I have the trip time set on the PSX breakers set to the minimum trip time.

There are other hints here:

https://sites.google.com/site/markgurries/home/nce-info/nce-accessories/nce-dcc-circuit-breakers/eb1-info

Hope that helps, Ed

 

Thanks for all the info.  I’ll read through it.  I believe I have the EB1’s set to trip at teh lowest voltage so I’m not sure what else i can do to get them to trip before the Command station.  Maybe the answers are in the links you provided.

Thank you

Gary

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Posted by BigDaddy on Thursday, February 22, 2018 5:59 PM

gdelmoro
So what is the correct way to send power to the breakers?

That was sort of my point.  Even powering separate circuit breakers directly from the command station is no different than a terminal strip or a a PSX daisy chain that takes place proximal (before) any of the circuit breaker circuitry.

I see the black wire that runs to the right of the circuit breakers.  Is that the input power?

 

Henry

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Posted by richhotrain on Thursday, February 22, 2018 6:14 PM

rrinker

Looking at the picture, I see something suspicious already. I see a pair of wires comming from the track terminals to the terminal block, which then splits off to feed each EB-1. That's fine, all wired in parallel, they aren;t downstream of one another, that's the correct way to wire them. But i ALSO see another pair of wires coming from the command station and going back up alongside the right hand EB-1 and off to the layout somewhere. Where's that go? A short across those wires will shut the system off and none of the EB-1s will trip. What do those wires connect to? 

Randy, if you are referring to the black cable coming off the left side of the command station, that is the booster cable on the PH-Pro, Gary must have the power supply sitting somewhere outside of the photo.

Rich

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Posted by gdelmoro on Thursday, February 22, 2018 6:22 PM

Randy, Thanks, I’ll check it all out and get back.

The black wire to the right of the EB1’s comes from the power supply on the top left of the photo and feeds directly into the power terminal on the Command station.

I thought my independent confirming that each district was dead when the breaker was disconnected and individually powered when connected eliminated any misconnected feeders. No?

I’ll check the other questions out tomorrow.

Gary

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Posted by gdelmoro on Thursday, February 22, 2018 6:39 PM

This is the power supply that is connected directly into the “power” connector on the command station.

 

Gary

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Posted by BigDaddy on Thursday, February 22, 2018 6:39 PM

gdelmoro
I thought my independent confirming that each district was dead when the breaker was disconnected and individually powered when connected eliminated any misconnected feeders. No?

I'm not the guru but here are my two theories

The NCE breaker is a piece of stuff and backfeeds the short to the entire system.  In which case the quarter test in each of your 3 segments will be the same because NCE breakers cannot be connected or trusted.

The Main breaker is defective, or there is some other information that is still unknown. 

At this point, I am leaning toward solution 2.  If NCE made circuit breakers that could only be used for a single block, we would have heard about it by now.

And yes, everyone should do the quarter test for each block, always.

 

 
 
 

Henry

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Posted by richhotrain on Friday, February 23, 2018 6:04 AM

gdelmoro

I thought my independent confirming that each district was dead when the breaker was disconnected and individually powered when connected eliminated any misconnected feeders. No? 

I'm not so sure that disconnecting individual or multiple circuit breakers proves all that much.

With all the circuit breakers connected, a better test, as others have pointed out, is to use the quarter test on each power district. That way, if the entire layout shuts down, you know that you have a problem, either with the wiring or with one or more of the circuit breakers.

One thing that you know for sure is that your booster is working correctly since it shut down the layout when the quarter test shorted the system, exceeding 5 amps in the process.

It seems likely that the three circuit breakers are either not wired properly or, more likely, that the trip current adjustments are set higher than the 5 amp booster. 

I also wonder if the EB1s react too slowly.  If that is the case, spend some bucks and buy the PSX circuit breakers. 

Rich

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Posted by rrinker on Friday, February 23, 2018 6:32 AM

16ms is pretty fast. And it's an all-electronic breaker, the same as a PSX. Don't know why NCE would design a circuit breaker that didn't worj with their own system.

 Need to double check the trip current jumpers, a single jumper on one end is 3.5 amps, good, but if it's on the opposite end it sets it to like 9 amps, not so good. Easiest test - take all jumpers off. No jumpers is 2.5 amps, definitely less than the booster output, so the breaker should trip first.

                                        --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by gdelmoro on Sunday, February 25, 2018 7:59 AM

Randy

jumper was on 4 Amps. B position. Moved to A 3.5. 

Quarter on Maun EB1 blinks but does not reset unless I shut the Syst and turn back on. 

Ferry and Sort yard yard trips All breakers. When quarter removed breakers come back on  

remove ALL jumpers

Main - Ferry - Yard  now trip all breakers.

back to checking feeders 

 

Gary

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Posted by BigDaddy on Sunday, February 25, 2018 8:42 AM

The yard breakers are doing something different than the Main breaker.  I cannot fathom how a quarter in the Ferry yard should affect the Main or Sort yard if they are elecrically isolated. 

Could NCE have designed a circuit breaker that needs it's own separate power supply?   According to the NCE Zen Desk, no ....multiple EB1's can run off a single booster.

I recall someone had a short last year in a DCC system that was related to remaining feeders from the previous DC system.

There is something you have yet to discover about your wiring.

 

 

Henry

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Posted by gdelmoro on Tuesday, February 27, 2018 6:18 AM

richhotrain

 

 
gdelmoro

I thought my independent confirming that each district was dead when the breaker was disconnected and individually powered when connected eliminated any misconnected feeders. No? 

 

 

I'm not so sure that disconnecting individual or multiple circuit breakers proves all that much.

 

With all the circuit breakers connected, a better test, as others have pointed out, is to use the quarter test on each power district. That way, if the entire layout shuts down, you know that you have a problem, either with the wiring or with one or more of the circuit breakers.

One thing that you know for sure is that your booster is working correctly since it shut down the layout when the quarter test shorted the system, exceeding 5 amps in the process.

It seems likely that the three circuit breakers are either not wired properly or, more likekly, that the trip current adjustments are set higher than the 5 amp booster. 

I also wonder if the EB1s react too slowly.  If that is the case, spend some bucks and buy the PSX circuit breakers. 

Rich

 

OK I checked the track feeders on all track in the ferry yard. They are all connected to teh ferry yard bus line. The sorting yard is next.

Rich, the EB1 wiring is correct, I re-checked all wires.  I removed All jumpers which now trips the breakers at 2.5 AMPS. Do you think for some reason the short os registering with the Command station before the breakers trip? Does the PSX breaker react faster?

Gary

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Posted by richhotrain on Tuesday, February 27, 2018 6:34 AM

gdelmoro

Rich, the EB1 wiring is correct, I re-checked all wires.  I removed All jumpers which now trips the breakers at 2.5 AMPS. Do you think for some reason the short os registering with the Command station before the breakers trip? Does the PSX breaker react faster? 

I think that is one possibility although Randy thinks differently, and I respect his opinion. So, I cannot say that for sure.

I will say that I had a similar problem when I had Digitrax AR-1s on my layout. When I added some PSX circuit breakers to protect my newly created power districts, I had to swap out the AR-1s for PSX-ARs since the PSX was reacting quicker than the AR-1. 

Now, admittedly, the EB1 may be constructed differently than the AR-1 which operated off of a mechanical relay. And, also, as Randy points out, since your booster and the EB1 are both NCE products, it is difficult to imagine that they wouldn't work well together.

But, if your wiring and gapping are flawless, then the problem would seem to be with the EB1.

Let's look at this from a different perspective. Let's say that the EB1 is working correctly and that it trips when the current exceeds 3.5 amps, so that it shuts down its power district it is supposed to protect without shutting down the other EB1 protected power districts.  OK, so now what?  What is left to consider?  Yep, improper wiring or gapping.

Rich

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Posted by gdelmoro on Tuesday, February 27, 2018 6:47 AM

Yea, thats what I’m thinking.  certinally  will be cheaper but it’s going to take a while to check all those feeders. Sad

Gary

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Posted by richhotrain on Tuesday, February 27, 2018 6:58 AM

Gary, in thinking more about this problem, is there any other circuitry on your layout that feeds into those EB1s?

Also, another simple test would be to disconnect the wiring from the terminal block and pigtail the three wires from the input side of the three EB1s to the wire from the command station currently feeding into the terminal block. Do this for the red wires and a separate pigtail for the black wires.

I would be interested to see if that makes any difference. Perhaps the problem is with the setup of the terminal block. Doubt it but you never know.

Rich

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Posted by richhotrain on Tuesday, February 27, 2018 7:04 AM

Here is another thing you might do if it has not already been suggested.

Disconnect the two yards from the output side of their EB1s, so that only the main line is powered.  Do the quarter test.

If the EB1 shuts down the main line before the short reaches the booster, disconnect the main line from the EB1 and connect one of the yards to the output side of its EB1. Do the quarter test.

If the EB1 shuts down the yard before the short reaches the booster, disconnect the yard from the EB1 and connect the other yard to the output side of its EB1. Do the quarter test.

Rich

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Posted by rrinker on Tuesday, February 27, 2018 7:22 AM

 It wouldn;t hurt to double check the CV that controls the trip time and make sure it is on the defulat of 16ms. Enough gerfingerpoken and you could have accidently set it to something higher which would allow the command station to trip first.

Something else to try to eliminate the EB-1 - disconnect the outputs of all 3. Take a short piece of wire and one at a time, short right at the output of each EB-1 and see if the EB-1 trips or the nain system breaker trips. Make sure the trip speed is set correctly first. If everything works shorting right at the EB-1, then you know the issue is in the layout wiring. If two EB-1s work and the third one doesn't, you likely have a defective EB-1.

                                                --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by BigDaddy on Tuesday, February 27, 2018 7:24 AM

I thought it was established in the Sunday morning post that the breakers were tripping and not the command station.   Maybe I misread the post.

Is there not an overload led on one of these components that lights up when it is tripped?

 
 

Henry

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Posted by richhotrain on Tuesday, February 27, 2018 7:31 AM

BigDaddy

I thought it was established in the Sunday morning post that the breakers were tripping and not the command station.   Maybe I misread the post.

Is there not an overload led on one of these components that lights up when it is tripped?

I don't know if we are certain of that. What is shutting down the power to one or more power districts?  The EB1 or the booster? 

Rich

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Posted by BigDaddy on Tuesday, February 27, 2018 8:19 AM

I enlarged the 1st photo and it looks like a standard European barrier strip.  The booster input goes to (from left to right)

Black 1 and Red 2

  • 1 is jumpered to 3 and 5
  • 2 is jumpered to 4 and 6
  • all on the input side
  • on the output side 1 & 2, 3 & 4, 4 & 6 look like they are feeding separate EB1's

It doesn't look like much can go wrong there.  Twisting the wires together doesn't seem like it would be electrically different.

The EB1 is programmable by CV's  I don't know how hard it is to inadvertently change those settings.

 

Henry

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Posted by richhotrain on Tuesday, February 27, 2018 10:11 AM

BigDaddy

I enlarged the 1st photo and it looks like a standard European barrier strip.  The booster input goes to (from left to right)

Black 1 and Red 2

  • 1 is jumpered to 3 and 5
  • 2 is jumpered to 4 and 6
  • all on the input side
  • on the output side 1 & 2, 3 & 4, 4 & 6 look like they are feeding separate EB1's

It doesn't look like much can go wrong there.  Twisting the wires together doesn't seem like it would be electrically different.

The EB1 is programmable by CV's  I don't know how hard it is to inadvertently change those settings. 

Yeah, I see your point, Henry. That type of terminal block seems hard to screw up. Still.....

I would still like to test the input wiring by bypassing the terminal block. I like the pigtail idea, given the nature of the problem.

I am not familiar with the EB1. Can the trip current adjustment only be performed by changing CV values?  No physical jumpers?

Rich

Alton Junction

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