Re: DCC Wiring - Can it cause a fire?

Steve Haas

In response to my comment:

“  . . . keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.”,

Bob inquired:

“Are you suggesting gaps closer to or farther from the frog?  Could you explain what you mean with a little more detail? Or point us to a diagram or discussion.>>

The Fouling point is the location where equipment on the diverging tracks of a turnout would sideswipe each other.  Trains & equipment need to be spotted beyond the fouling point so equipment can move into/out of the adjacent track without sideswiping each other.

Starting from the point end of a turn out, you have points, frog, fouling point.  Your gaps go between the frog and the fouling point.  These gaps should be as close to the frog as is reasonably possible given the track construction methods used.

The rationale is this – In theory, (most, there are always exceptions <>) operators will keep equipment beyond the fouling point so trains don’t snag on each other.  If they do that (as they should), and the gaps are between the frog and the fouling point, the metal wheels of stopped equipment are unlikely to span the gap, potentially creating a short if the turnout is thrown against the equipment spanning that gap.

We had an incident on a local layout where this actually occurred.  Track was hand laid, and one side of the frog extended about six inches down the yard track.  A train entered the track from the far end of the yard and pulled down to the far end, where it stopped with one of its front wheels spanning the frog gap.  As the engineer was moving slow, he was almost stopped when tht axle spanned that gap, and didn’t notice that he’d straddled the gap.  The turnout was against him, so the frog was one polarity and the rail under the train the opposite.   Additionally this was the last train of the session, so the short went completely un-noticed.  The layout was shut down and we went to beans.  Several work sessions passed where we had track power on for various reasons.  When we finally went to move the train for re-staging purposes, it wouldn’t move.  Inspection revealed that the gear on the front axle had gotten so hot that the plastic had flowed around the bearing block on that side of the axle, and had cooled around the bearing block effectively freezing the mechanism.  Layout owner, not realizing that any of this had happened, attempted to move the train by turning up speed on throttle.  Only thing that happened is track to decoder and decoder to motor wiring got hot and the insulation burned off.

All of this would have been avoided if the gaps had placed properly  (between the frog and the fouling point originally.

Best regards,

Steve Haas

Snoqualmie, WA

Are you suggesting gaps closer to or farther from the frog?  Could you explain what you mean with a little more detail? Or point us to a diagram or discussion.

Thanks!

bob

Good construction minimizes a host of errors – keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.

Best regards,

Steve Haas

Snoqualmie, WA

size=2 width="100%" align=center>

Re: DCC Track Design for review

Carl

Hi Gang:

Second try, it is in the files:

https://groups.yahoo.com/neo/groups/WiringForDCC/files

You need the full name to find it: "Final Layout for review".

Share your goals for your layout. The tracks run very close to the edges for any scenery.  The four parallel tracks look like they have a station between them. Are you interested in passenger service? Only a few sidings so perhaps not freight switching. Turntable and round house so the age of steam?

Do you plan to move the layout often? Can you work it from all sides? What space do you have available?

Electrically it is simple, plenty of blocks and only one reversing track, the green diagonal, if you don't count the turntable track.

Let us know. Carl

On 1/23/2014 12:42 AM, Carl wrote:

Hi Gang:

How about coping the web link so we all don't need to waste time searching at all?

I think I found it in photos:

https://groups.yahoo.com/neo/groups/WiringForDCC/photos/albums/85627517

Files had no "Layout for Review".

Carl.

On 1/22/2014 10:52 PM, Paul O wrote:

Railandsail, go to the WiringForDCC Yahoo group; on the left side, click on FILES.

The first half of that section is folders and the second half is individual files.

Scroll down until you come to "Layout for Review".

Paul O

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of railandsail
Sent: Wednesday, January 22, 2014 10:41 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] DCC Track Design for review

How do you find that "FILES" section, and your "Layout for Review" ??

Re: DCC Track Design for review

Carl

Hi Gang:

How about coping the web link so we all don't need to waste time searching at all?

I think I found it in photos:

https://groups.yahoo.com/neo/groups/WiringForDCC/photos/albums/85627517

Files had no "Layout for Review".

Carl.

On 1/22/2014 10:52 PM, Paul O wrote:

Railandsail, go to the WiringForDCC Yahoo group; on the left side, click on FILES.

The first half of that section is folders and the second half is individual files.

Scroll down until you come to "Layout for Review".

Paul O

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of railandsail
Sent: Wednesday, January 22, 2014 10:41 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] DCC Track Design for review

How do you find that "FILES" section, and your "Layout for Review" ??

Re: DCC Track Design for review

Bob Hand <rehandjr@...>

Click "Messages in this topic" at the bottom of this email message.  Logon.  You will be in Conversations (it will be bolded).  Click Files and you will be there.

bob

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of Ed S
Sent: Wednesday, January 22, 2014 11:18 PM
To: WiringForDCC@...
Subject: RE: [WiringForDCC] DCC Track Design for review

I have the NEO version of yahoo and I cannot find it in the files section.

I hate Neo.

Ed S

At 10:52 PM 1/22/2014, you wrote:
>
>
>Railandsail, go to the WiringForDCC Yahoo group; on the left side,
>click on FILES.
>
>The first half of that section is folders and the second half is
>individual files.
>
>Scroll down until you come to "Layout for Review".
>
>
>
>Paul O
>
>

Re: DCC Track Design for review

Scott H. Haycock

Ed,

Click on the "visit your group" at the bottom of this post where it says recent activity. When the Yahoo groups page comes up, click on  "Wiring For DCC" in the column on the left, showing the groups you belong to. Next click on "Files". Now go to the right side and change from "Alphabetical" to "Latest first". now scroll down. The 21st item, with the red PDF icon is what you want. Clicking on that will download the plan to your computer. I know, it's a pain, but after a while, you'll get the hang of it.

Scott Haycock
Modeling Tarheel country in the Land of Enchantm
ent

I have the NEO version of yahoo and I cannot find it in the files section.

I hate Neo.

Ed S

At 10:52 PM 1/22/2014, you wrote:
>
>
>Railandsail, go to the WiringForDCC Yahoo group; on the left side,
>click on FILES.
>
>The first half of that section is folders and the second half is
>individual files.
>
>Scroll down until you come to "Layout for Review".
>
>
>
>Paul O
>
>

Re: DCC Track Design for review

Flash Gordon

I have the NEO version of yahoo and I cannot find it in the files section.

I hate Neo.

Ed S

At 10:52 PM 1/22/2014, you wrote:

Railandsail, go to the WiringForDCC Yahoo group; on the left side, click on FILES.

The first half of that section is folders and the second half is individual files.

Scroll down until you come to "Layout for Review".

Paul O

Re: DCC Track Design for review

Chuck Stiles

Paul

I will probably tie most block to the Buss
I'm thinking some block occupancy detection in the future for signals
Most will be tied to terminal strips in the event I need troubleshooting
I may try light bulbs for short detection
I'd rather have more feeders now than try to add them in the future
I will probably be the lone operator

Chuck

On Wednesday, January 22, 2014 11:01 PM, Paul O wrote:
Chuck, it looks like a good plan.
One question: It looks like you have about 25 separate blocks. What is you plan for these blocks?
n  Individual circuit breakers?
n  Auto light bulbs?
n  Grouping them to a terminal block for troubleshooting ease?

The reverse loop shouldn’t be a problem so long as the isolated section is longer than any train you plan to run thru it.

Do you plan to be a lone operator or have multiple operators?

Paul O

From:  Chuck Stiles

Hi I'm new to the group and DCC but not to the hobby
Its been over 30 years since I built my last layout (a lot has changed since then)
I have been doing a lot of reading & research. I designed a new layout 5 x 8'  the table is built and ready to go (you can see it in the FILES section) "Final Layout for Review"
I am proficient with auto cad so after I tried some of the available free programs like Any Rail I decided to do it in autocad so I can get may track spacing and radius geometry correct.
I have Purchased Peco electrofrog turn out switch Peco 100 Flex Track its going over an old school cork roadbed and ballast
I have purchased tortoise switch machines as well
I built the Walthers Turntable and its ready for install
The uploaded drawing shows my proposed track layout with isolator locations track feed locations and block identification
I plan on wiring the elecrofrog thru the tortoise as per many online recommendations I have read
The purchase of the other DCC controls I have not fully decided on, I am planning on building a fascia control panel for switch control as well as control from a handheld throttle. In the future I would like to experiment with PC control using JMRI software (but one step at a time).
I'm welcoming anyone to look at my plan and see if I may have over looked something thus far before a start making things permanent.
There is a reversing section across the middle that I had concerns about wiring a reversing module

Thanks
Chuck Stiles
NJ

Re: DCC Track Design for review

Paul O

Chuck, it looks like a good plan.

One question: It looks like you have about 25 separate blocks. What is you plan for these blocks?

n  Individual circuit breakers?

n  Auto light bulbs?

n  Grouping them to a terminal block for troubleshooting ease?

The reverse loop shouldn’t be a problem so long as the isolated section is longer than any train you plan to run thru it.

Do you plan to be a lone operator or have multiple operators?

Paul O

From:  Chuck Stiles

Hi I'm new to the group and DCC but not to the hobby

Its been over 30 years since I built my last layout (a lot has changed since then)

I have been doing a lot of reading & research. I designed a new layout 5 x 8'  the table is built and ready to go (you can see it in the FILES section) "Final Layout for Review"

I am proficient with auto cad so after I tried some of the available free programs like Any Rail I decided to do it in autocad so I can get may track spacing and radius geometry correct.

I have Purchased Peco electrofrog turn out switch Peco 100 Flex Track its going over an old school cork roadbed and ballast

I have purchased tortoise switch machines as well

I built the Walthers Turntable and its ready for install

The uploaded drawing shows my proposed track layout with isolator locations track feed locations and block identification

I plan on wiring the elecrofrog thru the tortoise as per many online recommendations I have read

The purchase of the other DCC controls I have not fully decided on, I am planning on building a fascia control panel for switch control as well as control from a handheld throttle. In the future I would like to experiment with PC control using JMRI software (but one step at a time).

I'm welcoming anyone to look at my plan and see if I may have over looked something thus far before a start making things permanent.

There is a reversing section across the middle that I had concerns about wiring a reversing module

Thanks

Chuck Stiles

NJ

Re: DCC Track Design for review

Bob Hand <rehandjr@...>

Logon to yahoo mail, go to your group (wiringfordcc), click files and it will be listed there. (that is how I get there...).

bob

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of railandsail
Sent: Wednesday, January 22, 2014 10:41 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] DCC Track Design for review

How do you find that "FILES" section, and your "Layout for Review" ??

On Wed, Jan 22, 2014 at 6:08 PM, Chuck Stiles wrote:

Hi I'm new to the group and DCC but not to the hobby
Its been over 30 years since I built my last layout (a lot has changed since then)
I have been doing a lot of reading & research. I designed a new layout 5 x 8'  the table is built and ready to go (you can see it in the FILES section) "Final Layout for Review"
I am proficient with auto cad so after I tried some of the available free programs like Any Rail I decided to do it in autocad so I can get may track spacing and radius geometry correct.
I have Purchased Peco electrofrog turn out switch Peco 100 Flex Track its going over an old school cork roadbed and ballast
I have purchased tortoise switch machines as well
I built the Walthers Turntable and its ready for install
The uploaded drawing shows my proposed track layout with isolator locations track feed locations and block identification
I plan on wiring the elecrofrog thru the tortoise as per many online recommendations I have read
The purchase of the other DCC controls I have not fully decided on, I am planning on building a fascia control panel for switch control as well as control from a handheld throttle. In the future I would like to experiment with PC control using JMRI software (but one step at a time).
I'm welcoming anyone to look at my plan and see if I may have over looked something thus far before a start making things permanent.
There is a reversing section across the middle that I had concerns about wiring a reversing module

Thanks
Chuck Stiles
NJ

Re: DCC Track Design for review

Paul O

Railandsail, go to the WiringForDCC Yahoo group; on the left side, click on FILES.

The first half of that section is folders and the second half is individual files.

Scroll down until you come to "Layout for Review".

Paul O

From: WiringForDCC@... [mailto:WiringForDCC@...] On Behalf Of railandsail
Sent: Wednesday, January 22, 2014 10:41 PM
To: WiringForDCC@...
Subject: Re: [WiringForDCC] DCC Track Design for review

How do you find that "FILES" section, and your "Layout for Review" ??

Re: DCC Track Design for review

Brian Eiland

How do you find that "FILES" section, and your "Layout for Review" ??

On Wed, Jan 22, 2014 at 6:08 PM, Chuck Stiles wrote:

Hi I'm new to the group and DCC but not to the hobby
Its been over 30 years since I built my last layout (a lot has changed since then)
I have been doing a lot of reading & research. I designed a new layout 5 x 8'  the table is built and ready to go (you can see it in the FILES section) "Final Layout for Review"
I am proficient with auto cad so after I tried some of the available free programs like Any Rail I decided to do it in autocad so I can get may track spacing and radius geometry correct.
I have Purchased Peco electrofrog turn out switch Peco 100 Flex Track its going over an old school cork roadbed and ballast
I have purchased tortoise switch machines as well
I built the Walthers Turntable and its ready for install
The uploaded drawing shows my proposed track layout with isolator locations track feed locations and block identification
I plan on wiring the elecrofrog thru the tortoise as per many online recommendations I have read
The purchase of the other DCC controls I have not fully decided on, I am planning on building a fascia control panel for switch control as well as control from a handheld throttle. In the future I would like to experiment with PC control using JMRI software (but one step at a time).
I'm welcoming anyone to look at my plan and see if I may have over looked something thus far before a start making things permanent.
There is a reversing section across the middle that I had concerns about wiring a reversing module

Thanks
Chuck Stiles
NJ

Re: 10 amp booster Re: DCC Wiring - Can it cause a fire?

Mark Gurries

V = I * R

Ohms law re-writen to solve for ohms

R = V / I

The equation is setup like this:

Ohms(Wiring) = V(track) / I(booster)

For the 10Amp booster, I(booster) = 10A and Vtrack = 16V (Factory setting)

Ohms = 16V / 10A = 1.6 Ohms per advertised specifications.

However in practice the 10Amp booster puts out close to 12Amps  (Production design margin to guarantee 10amps) which mean the actual real value is closer to 1.3 Ohms.

This is the maximum resistance value one can tolerated from one track terminal on the booster out and around the layout all the back to the other terminal of the same booster.  Your layout wiring should make sure it is less than this value.  Hence the quarter test does just that.  If a short circuit between the rails does not shutdown the booster, you have a wiring problem with to much resistance which in this case means you have more than 1.3 Ohms.

On Jan 22, 2014, at 7:00 AM, madog wrote:

What would the ohms be on a 10 amp booster?
I’m in 2 rail O Scale
Bill Kozel

From: Steve Haas
Sent: Tuesday, January 21, 2014 11:52 PM
Subject: RE: [WiringForDCC] Re: DCC Wiring - Can it cause a fire?

<<If there is a highly resistive connection somewhere in the wiring that is more than about 2.8 ohms when using a 5Amp booster and there is a short circuit on the track,  that resistive point is where all the heat will be because the booster will not have shutdown but instead deliver full power.>>

A local layout has hand laid track and turnouts with powered frogs.  The original track layers and electricians were not too careful about where they cut the gaps beyond turnouts.  We’ve lost the side frames of two different engines to excessive heat when the front wheel set of the engines spanned the gap that isolated the frog from the yard track.

Good construction minimizes a host of errors – keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.

Best regards,

Steve Haas

Snoqualmie, WA

Best Regards,

Mark Gurries
Electrical Engineer
DCC Website & NMRA DCC Clinics: www.markgurries.com

DCC Track Design for review

Chuck Stiles

Hi I'm new to the group and DCC but not to the hobby
Its been over 30 years since I built my last layout (a lot has changed since then)
I have been doing a lot of reading & research. I designed a new layout 5 x 8'  the table is built and ready to go (you can see it in the FILES section) "Final Layout for Review"
I am proficient with auto cad so after I tried some of the available free programs like Any Rail I decided to do it in autocad so I can get may track spacing and radius geometry correct.
I have Purchased Peco electrofrog turn out switch Peco 100 Flex Track its going over an old school cork roadbed and ballast
I have purchased tortoise switch machines as well
I built the Walthers Turntable and its ready for install
The uploaded drawing shows my proposed track layout with isolator locations track feed locations and block identification
I plan on wiring the elecrofrog thru the tortoise as per many online recommendations I have read
The purchase of the other DCC controls I have not fully decided on, I am planning on building a fascia control panel for switch control as well as control from a handheld throttle. In the future I would like to experiment with PC control using JMRI software (but one step at a time).
I'm welcoming anyone to look at my plan and see if I may have over looked something thus far before a start making things permanent.
There is a reversing section across the middle that I had concerns about wiring a reversing module

Thanks
Chuck Stiles
NJ

10 amp booster Re: DCC Wiring - Can it cause a fire?

Bill><>

What would the ohms be on a 10 amp booster?
I’m in 2 rail O Scale
Bill Kozel

From: Steve Haas
Sent: Tuesday, January 21, 2014 11:52 PM
Subject: RE: [WiringForDCC] Re: DCC Wiring - Can it cause a fire?

<<If there is a highly resistive connection somewhere in the wiring that is more than about 2.8 ohms when using a 5Amp booster and there is a short circuit on the track,  that resistive point is where all the heat will be because the booster will not have shutdown but instead deliver full power.>>

A local layout has hand laid track and turnouts with powered frogs.  The original track layers and electricians were not too careful about where they cut the gaps beyond turnouts.  We’ve lost the side frames of two different engines to excessive heat when the front wheel set of the engines spanned the gap that isolated the frog from the yard track.

Good construction minimizes a host of errors – keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.

Best regards,

Steve Haas

Snoqualmie, WA

Re: DCC Wiring - Can it cause a fire?

Bob <rehandjr@...>

Hi Steve,

Are you suggesting gaps closer to or farther from the frog?  Could you explain what you mean with a little more detail? Or point us to a diagram or discussion.

Thanks!

bob

<<If there is a highly resistive connection somewhere in the wiring that is more than about 2.8 ohms when using a 5Amp booster and there is a short circuit on the track,  that resistive point is where all the heat will be because the booster will not have shutdown but instead deliver full power.>>

A local layout has hand laid track and turnouts with powered frogs.  The original track layers and electricians were not too careful about where they cut the gaps beyond turnouts.  We’ve lost the side frames of two different engines to excessive heat when the front wheel set of the engines spanned the gap that isolated the frog from the yard track.

Good construction minimizes a host of errors – keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.

Best regards,

Steve Haas

Snoqualmie, WA

Re: DCC Wiring - Can it cause a fire?

Steve Haas

<<If there is a highly resistive connection somewhere in the wiring that is more than about 2.8 ohms when using a 5Amp booster and there is a short circuit on the track,  that resistive point is where all the heat will be because the booster will not have shutdown but instead deliver full power.>>

A local layout has hand laid track and turnouts with powered frogs.  The original track layers and electricians were not too careful about where they cut the gaps beyond turnouts.  We’ve lost the side frames of two different engines to excessive heat when the front wheel set of the engines spanned the gap that isolated the frog from the yard track.

Good construction minimizes a host of errors – keep those gaps inside the fouling point of your turnouts and equipment and it will reduce the number of problems due to shorts by reducing the possibility of shorts.

Best regards,

Steve Haas

Snoqualmie, WA

Re: DCC Wiring - Can it cause a fire?

Mark Gurries

On Jan 21, 2014, at 11:52 AM, Robert Morrison wrote:

Good idea about the lighted switch for layout power circuits. I did this at my old home, but not yet at the new one.
Of course, since most of my locomotives have steam sound decoders, there is enough noise to alert me when I leave.
Nevertheless, my next project is to get a circuit with a lighted switch at the entrance to the layout.

I use 20 AWG wire for the drops to every piece of rail, no drop is more than 12 inches long.
Joiners are for rail alignment only.
Main power bus is 12 AWG.
All sections of the layout do trigger the circuit breakers when shorted with a quarter or screw driver.

Excellent.

An idea:
After the layout power is on for a while, go around feeling the wires, especially the drops and solder joints for heat build up.
That might tell you if there is a greater potential for fire.

The only time you will get heat is if there is a short circuit that fails to trip any DCC circuit breaker or booster.   Hence the purpose of the coin short circuit test which makes sure the resistance in the wiring is low enough.

If there is a highly resistive connection somewhere in the wiring that is more than about 2.8 ohms when using a 5Amp booster and there is a short circuit on the track,  that resistive point is where all the heat will be because the booster will not have shutdown but instead deliver full power.

Best Regards,

Mark Gurries
Electrical Engineer
DCC Website & NMRA DCC Clinics: www.markgurries.com

Re: DCC Wiring - Can it cause a fire?

Robert Morrison <Robmorrison@...>

Good idea about the lighted switch for layout power circuits. I did this at my old home, but not yet at the new one.
Of course, since most of my locomotives have steam sound decoders, there is enough noise to alert me when I leave.
Nevertheless, my next project is to get a circuit with a lighted switch at the entrance to the layout.

I use 20 AWG wire for the drops to every piece of rail, no drop is more than 12 inches long.
Joiners are for rail alignment only.
Main power bus is 12 AWG.
All sections of the layout do trigger the circuit breakers when shorted with a quarter or screw driver.

An idea:
After the layout power is on for a while, go around feeling the wires, especially the drops and solder joints for heat build up.
That might tell you if there is a greater potential for fire.

What do you think?

Rob

Re: DCC Wiring - Can it cause a fire?

Flash Gordon

Good idea, I am doing the same.

Ed S

At 06:35 PM 1/20/2014, you wrote:

Re-wired the new layout with a lighted, main power switch. Located at the door entering the layout. One look at that switch and you know immediately if the room is "powered" or not. Single best improvement I ever made to a layout. I never leave the area without knowing.

George

On Jan 20, 2014, at 2:28 PM, "rheroux@..." <rheroux@...> wrote:

power off..... I do...

Just my two cents....

Bob

Re: DCC Wiring - Can it cause a fire?

george hohon3

Re-wired the new layout with a lighted, main power switch. Located at the door entering the layout. One look at that switch and you know immediately if the room is "powered" or not. Single best improvement I ever made to a layout. I never leave the area without knowing.

George

On Jan 20, 2014, at 2:28 PM, "rheroux@..." <rheroux@...> wrote:

Lets all face it... When not running your railroad.... Turn the power off..... I do...

Just my two cents....

Bob

On Jan 20, 2014, at 2:07 PM, madog <@BillK> wrote:

WOW!
Thanks for that tid-bit!!!!
Bill Kozel

From: David Heine
Sent: Monday, January 20, 2014 2:28 PM
To: WiringForDCC@...
Subject: RE: [WiringForDCC] DCC Wiring - Can it cause a fire?

In general, a circuit breaker doesn’t know the difference between 5 amps of load, 5 amps caused by a short with the current limited by inadequate wiring, or 5 amps caused by a higher impedance short that limits the current to 5 amps by itself. In this case, I would suspect a short with inadequate wiring or some sort of higher impedance short.

I knew better, but on a previous layout, I let my track laying get ahead of my wiring. I had about 25’ of track (50’ of Code 70 rail) beyond the last set of track feeders. I was test running an engine, it derailed and caused a short. Because of the resistance of all the rail, the current level was held below the value for the protection to trip the power (5A). I had to shut off the power manually. The short was on long enough to melt the Kadee coupler box on the tender of a brass locomotive.

Dave Heine

Easton, PA

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Robert Heroux
ACCU-LITES, Inc.