Using terminal strips for DCC wiring

[dtabor]

Based on my last question, some mentioned terminal strips for wiring a DCC system. Most of what Ive read/watched shows a continuous buss line and the feeders attached every 3-6' along that, and the best practice is to keep the feeders as short as possible for less power loss. Wondering what the advantage of a terminal strip is and how that works with feeders. It seems if I have a terminal strip in a certain place, that the feeders from that strip to the track would get long. Do you use a small terminal block at each feeder point? Seems that would be a ton of terminal blocks if you had a long main line. There are some youtube videos showing terminal blocks/strips but I cant find one that shows the whole process of wiring the actual feeder points.

[BATMAN]

This bench is 18' long, I have a terminal strip at one end and the buss wires run the length of the bench like fingers. I hook the feeders to the wire right under the track by wrapping the feeder wire around the buss and soldering it. I just stripped the buss maybe 1/4" in each spot, soldered the wire on and slapped some liquid electrical tape on it.

 

I mounted it on this flip-down board under the layout.

 

This is the other side of the room. I had 100s of feet of 12g wire sitting around so I went a little overboard. The layout is 15 years old and I have never had one electrical issue.

 

 

[York1]

dtabor

Based on my last question, some mentioned terminal strips for wiring a DCC system. Most of what Ive read/watched shows a continuous buss line and the feeders attached every 3-6' along that, and the best practice is to keep the feeders as short as possible for less power loss.

 

I use the terminal strips.  On each terminal strip, all the screws are connected.

The bus wire is attached to one screw, and all the other screws then are out to the feeders.  I have two terminal strips at each location.

I found several advantages.  As Mike said, it makes things very easy to connect or disconnect, especially if you're trying to find a problem.

Another advantage is that these terminal strips are attached behind the removable fascia.  Wires are dropped under the table, and pulled to the terminal strips.  This allows me to never have to go under the table and work over my head.  All connections are done sitting in a chair.  For you younger readers, this may seem silly, but just wait until you get to my age.

I have these terminal strips at several different places on the layout, with the buss wire going to each one.  Not one of my feeder wires was over four feet with this system, so I don't think there's any problem with loss of power.

 

This picture is for lights on the layout, but I use the same system for the power feeders and buss.

 

Here's a sample of what I used.  These come in quite a few different sizes:

 

Edit:  Brent beat me to the post!  

[York1]

Lastspikemike

Each coating conceals a continuous metal strip connecting each seperate wire to the same polarity and to each other for the two separate bus wires power sources.  You could instead fit those bus bar type connectors onto the other side of these terminal strips.

Correct.

On the ones I bought, each set of screws is connected to the screw opposite it.  So the connectors only need to be on one side.  By connecting the buss wire to one screw, every screw on either side of the strip is connected.

It's a nice, easy, neat system.

For the feeder wires, it didn't make much difference, but for my lights, I regret not labeling each wire indicating where it went on the layout.

[RR_Mel]

I use shorting terminal blocks (busbars) in my control panel for main power distribution and EURO type connectors for terminal blocks for ease of connecting the wires.  Been using them for the last 30 or so years without any problems.

https://led-switch.com/collections/terminal-blocks



My layout is pretty small at 10’ x 14’ with 121’ of mainline and I don’t use DCC bus wiring, I run a pair of #19 solid bell wire to each block from my control panel.  My blocks are approximately 8' long.  Longest track wire run is about 12’, no problems since I added DCC in 2005.

DCC bus wiring works great I just prefer individual block control.

EDIT:

I run dual mode on my layout, DCC or DC.  I have over 60 locomotives and only 13 DCC decoders.

 

Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Turned 84 in July, aging is definitely not for wimps.

[jjdamnit]

Hello All,

Let me clarify my response to a previous post...

My pike is a 4'x8' that sits on the bed in the computer/spare bed/train room.

It is comprised of 1-inch foam on 1/4-inch plywood framed with 1"x4" for rigidity.

There is no under-access for wiring.

Originally it was DC with two (2) cabs and common rail wiring to 16 blocks; some as small as a single 9-inch piece of sectional track, through Atlas block controllers.

My wiring solution was to carve 1/2-inch wide and 1/2-inch deep trenches in the foam.

I then used 1/2-inch Split Poly Loom; commonly used in automotive applications, and placed it in the trenches- -think prototypical utility tunnels.

This allowed for scenicing and painting of the foam base along with ballasting without permanently burying the wiring.

To accommodate the wiring for the Atlas remote switch machines I cut out an area approximately 1-foot square in the foam. This served as the "utility pit".

All the "utility tunnels" converge at this location.

From there the turnout and block wiring went to a control panel.

I used terminal (barrier) strips to connect the positive (+) side of the Atlas controllers from the control panel to each block.

The turnouts are still controlled by a separate wall wart and two (2) Capacitive Discharge Units (CDUs) wired to half of the turnout motors- -some are PECO units paired so both turnouts are controlled by one switch.

When I converted to DCC one side of the track feeders were already in place, from the DC wiring.

Rather than running a traditional power bus, and dropping feeders, I just added a single negative (-) feeder to the previous DC blocks.

I also removed several sets of insulated rail joiners to make five (5) power districts from a single 5 Amp booster, from the previous 16 DC blocks. 

Two (2) Walther's Northern Light & Power buildings were kitbashed to cover the booster/command station that sits on top of the pike.

Depending on the length of each power district there may be up to four (4) feeders from the centralized terminal strips to the track.

No feeder is longer than 3-feet from the booster/command station to the track.

With your particular track plan "radiating" power feeders would not be practical.

The traditional two (2) wire bus with track feeders would fit your application.

However, from the power booster/command station to the track bus terminal strips could be utilized.

The output of the booster would go to one side of the terminal strip. Additional jumpers would be used to energize the rest of the strip as has been posted.

From the other side of the terminal strip the three (3) legs of your power bus would "radiate".

One (1) to the crossover and the other two (2) to each leg along the walls.

An advantage to using terminal strips is if you want to add circuit breakers to each "power district" you simply need to wire them between the terminal strip and each section of the power bus- -after insulating each power district by gapping both rails or adding plastic insulated rail joiners.

My original post was meant to highlight the use of terminal strips and in no way imply that there is a single answer to each individual situation.

Hope this helps.

[richhotrain]

jjdamnit

My original post was meant to highlight the use of terminal strips and in no way imply that there is a single answer to each individual pike.

This seems to be your only post to this thread.

[jjdamnit]

Hello All,

dtabor

Based on my last question, some mentioned terminal strips for wiring a DCC system.

The OP referenced a previous post that I felt my response was ambiguous.

I am seeking to clarify my previous response.

Running bus wires

Hope this helps.

 

[richhotrain]

ahh, I see.

[jjdamnit]

Hello All,

richhotrain

ahh, I see.

Thank you for your kind response.

Hope this helps.

[richhotrain]

jjdamnit

richhotrain

ahh, I see. 

Thank you for your kind response.

Sure thing. I find your pike interesting, and your use of terminal strips interests me as well.

Rich

[SeeYou190]

Lots of different way to skin this cat.

-Photograph by Kevin Parson

-Kevin

[rrebell]

I don't use a single terminal strip. Why add to the wiring and since I use Posi-taps it is easy to trouble shoot and add or remove wires.

[dtabor]

I like the idea of the neat/clean looking terminal strips/bus bars but as was said above, it seems to add more unnecessary work and purchases. DCC is totally new to me so Ive been learning about it as I plan my new layout. It seemed the most common way to do it was run the buss lines underneath where the track lines are and use the shortest feeder wires possible, attaching to the buss via solder or suitcase connectors.

Lately Id seen many more posts and videos about using the terminal strips and couldnt see what the major advantage was.

I appreciate the community taking the time to answer all of my questions. Things have changed SO much since my last model railroad so its just like starting brand new for me.

[richhotrain]

Lastspikemike

Most home sized DCC layouts do not require a lot of wiring. Two wires to send power to two rails, literally. 

Otherwise unless you expect continuity or voltage drop issues you don't need a bus either. Just connect the DCC unit directly to a convenient section of track and the whole layout will be powered up. 

Well, there you go. Doggone it, I just assumed that since my layout is 42' x 25' that I would need to install a bus and run feeders to every section of track, be it flextrack or turnout. Had I only known that two wires from the command station would suffice. 

[RR_Mel]

When I designed and built my basic layout (bench work and track) it was for DC in 1988, before DCC for me.  It is 10’ x 14’ twice-around 121’ mainline.



There are 14 blocks of approximately 8’ per block.  I soldered all the joiners in each block.  I have always liked block design since my first layout in 1951.

When I bought my DCC controller in 2005 I rewired my layout to the DCC Guru specs.  Biggest mistake of my model railroading career.  Without blocks I lost all my block signal detection.  Being very disappointed after a couple of months I rewired it back to the original block design.

I was willing to give up on DCC but after the rewiring it to DC the DCC operation worked very good by just connecting the DCC controller to the DC wring, I had my signaling back.

I run dual mode DC or DCC operation, I only have 13 decoders and over 60 locomotives.

I have #19 solid bell wire feeing my blocks, longest run is under 20’ (1½ amps).  The max voltage loss to any track is less than .08 volts with two powered locomotives with sound and 13 fully illumined passenger cars.  Everything works great.

I use EURO connectors for termination of the track wiring at my control panel the other end of the #19 solid wire is soldered to the under side of the rails, 8’ section of track.
 
There are many many ways to wire your layout and I’m not knocking any of them just saying what works for me.  If I had longer block runs I would up the #19 wire to probably #16, which is good for 1½ amps at 30’.
 
 
Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Turned 84 in July, aging is definitely not for wimps.

[jjdamnit]

Hello All,

richhotrain

Well, there you go. Doggone it, I just assumed that since my layout is 42' x 25' that I would need to install a bus and run feeders to every section of track, be it flextrack or turnout. Had I only known that two wires from the command station would suffice. Super Angry

I'll just rip out all the wiring including the reversing wye and the four circuit breaker protection because it's "not a 'large' home layout".

Lastspikemike

There's a lot of belt and braces stuff in our hobby. Not necessary for everyone.

Good to know electrical safety is not necessary depending on the size of the layout.

Hope this helps.

[jjdamnit]

Hello All,

Hope this helps.

[SeeYou190]

Experience building 5 personal layouts, 2 club layouts, and 2 friend's layouts say this statement is untrue.

This is why only people with real experience should be answering questions.

jjdamnit

 

Lastspikemike

There's a lot of belt and braces stuff in our hobby. Not necessary for everyone.

 Good to know electrical safety is not necessary depending on the size of the layout.

Hope this helps.

 

See how much we are all learning from "He Who Knows Everything"?

Now I will not be wasting any more of my time on electrical safety hardware installation.

-Kevin

[jjdamnit]

Hello All,

Kevin, 

A recent observation from a new member, seeking sound guidance and advice getting back into this great hobby...

1971_Z28

I was beginning to notice there is not too much kindness in this group because some of you guys sure do like to argue about things to be smart.

Further down the same post...

1971_Z28

Mike (Lastspikemike) please do not respond to my threads because it did not take me long to see that you like arguments and cause threads to turn to garbage or stop and I do not want that happening to my questions.

SeeYou190

This is why only people with real experience should be answering questions.

“It's better to keep your mouth shut and appear stupid than open it and remove all doubt”- -Mark Twain

Hope this helps.

„It is better to keep your mouth shut and appear stupid than to open it and remove all doubt.“

Source: https://quotepark.com/quotes/780566-mark-twain-it-is-better-to-keep-your-mouth-shut-and-appear-st/

„It is better to keep your mouth shut and appear stupid than to open it and remove all doubt.“

Source: https://quotepark.com/quotes/780566-mark-twain-it-is-better-to-keep-your-mouth-shut-and-appear-st/“It's better to keep your mouth shut and appear stupid than open it and remove all doubt”

„It is better to keep your mouth shut and appear stupid than to open it and remove all doubt.“

Source: https://quotepark.com/quotes/780566-mark-twain-it-is-better-to-keep-your-mouth-shut-and-appear-st/

 

[DigitalGriffin]

I have terminal strips that connects to my bus using T-Taps to the bus and spade connectors to the terminal strip.

My connections are

+12V (yellow)

+5V (red)

Ground (black)

Rail + (white)

Rail - (blue)

 

I place a block every 4 feet or so.  The spades kind of get in the way of each other, so the best you'll do is about 6 spades (1 bus tap + 2 hookups on screw 1 and 3 more on screw 2)

[richhotrain]

I just don't get why this guy persists in repeatedly making statements that are generally known to be wrong. I cannot even begin to imagine powering my 42' x 25' layout with no bus and one pair of feeders from the command station.

I tend to glimpse at his posts just long enough to shake my head and move on. I feel bad for anyone who unwittingly accepts anything he says as true. 

Rich

[jjdamnit]

Hello All,

richhotrain

I just don't get why this guy persists in repeatedly making statements that are generally known to be wrong.
I cannot even begin to imagine powering my 42' x 25' layout with no bus and one pair of feeders from the command station.
I tend to glimpse at his posts just long enough to shake my head and move on. I feel bad for anyone who unwittingly accepts anything he says as true.

Many newcomers to this great hobby "ghost"  this site.

Some getting up enough courage to participate in the melee.

Others- -barge through the proverbial "Front Door" and proclaim their superiority and bestow their knowledge upon the uninformed membership.

For "Old Heads"- -FNGs aren't new.

The thought I have in mind when answering posts in these forums is "Primum Non Nocere"- -"First, Do No Harm."

If one post results in bringing clarity- -among the noise- -to answer a question that leads to the furtherment of our hobby, then so be it!!!

Hope this helps.

[rrebell]

richhotrain

I just don't get why this guy persists in repeatedly making statements that are generally known to be wrong. I cannot even begin to imagine powering my 42' x 25' layout with no bus and one pair of feeders from the command station.

I tend to glimpse at his posts just long enough to shake my head and move on. I feel bad for anyone who unwittingly accepts anything he says as true. 

Rich

 

Accually this is true until you start adding turnouts and other complexities.

[BATMAN]

What gauge wire is equal to code 83 rail?

 

[Water Level Route]

dtabor

Wondering what the advantage of a terminal strip is and how that works with feeders.

I'm not sure this ever really got answered in the mess that your thread unfortunately turned into.  Ideally, you have the shortest bus runs possible with the shortest feeders possible (within reason).  Hard to do placing your DCC system at one "end" of the layout.  If I recall, your layout has figure 8 shaped benchwork, yes?  To place your DCC booster at a location and run bus wire around the room and across the center of the "8" would likely mean a fairly long bus.  Not necessarily unworkable, but could be better.  Place your booster along one side of the "8", lets say the left side, right at the center.  Connect your booster to a terminal strip with all the screws on one side connected as has been shown in the thread.  Then run a bus from the terminal strip along the top loop of the "8".  Run another bus along the bottom loop of the 8, also connecting it at the terminal strip.  Finally, run a third bus across the center of the "8".  Makes for an easy way to connect up a wiring plan like this that minimizes wire run.  Obviously you drop your feeders from each section down to the corresponding bus.  While you could simply solder all the busses together and eliminate the terminal strips, should a problem arise, and you've electrically isolated the various sections of your layout fed by each respective bus, it's a simple matter of unscrewing and disconnecting a single post on the terminal strip to isolate a part of the layout for troubleshooting purposes.

BATMAN

What gauge wire is equal to code 83 rail?

 

 

Solid or stranded?  For solid wire, its 12awg.  For stranded, it falls between 12awg and 14 awg.

[DigitalGriffin]

BATMAN

What gauge wire is equal to code 83 rail?

It's a bit more complicated than that.  That assumes one long continuous piece of rail.  Wouldn't that be grand?

The point being rail joiners aren't made of nickel silver don't conduct high loads perfectly well.   Voltage drops occur through thin conductors and changes in material in combination with high current loads.

Now combine this with boosters or track districts, you are asking for damage to your boosters as voltage differences between districts/blocks can easily damage a booster or your locomotives!  I had this problem with blown NCE boosters at the club I helped convert to DCC.  Minor voltage differences can cause a huge issues.

Feeders are important on <edit>Frog</edit> rails on turnouts, and every few feet where joint breaks are present.  I use 14 gauge bus with 20 gauge feeders under a couple feet long.

For example:
Feed Gauge: 20
Distance: 3 ft
Voltage: 14 volt
Amps:  5

You'll get a .3V drop  on that feeder.

If you have two feeders, that drops to .15V

If you drop it down to 3 amps your voltage drop is .1V with two feeders.

Generally speaking using opto-isolated boosters with < .7V and a 3amp limit  breaker should be good enough to prevent most boosters from burning out.

That said 

Interestingly enough, Larry posted a video about this topic this very morning.

Don’t Blow Your Boosters (240) - YouTube

[Water Level Route]

Water Level Route

BATMAN What gauge wire is equal to code 83 rail?     Solid or stranded?  For solid wire, its 12awg.  For stranded, it falls between 12awg and 14 awg.

I should clarify that this is simply size equivalence, not equivalent conductive capability.

Lastspikemike

bus should be at least as good a conductor as the rails

Would be useful to have a knowledgeable individual comment on the differences between rail and wire here.  There is a reason virtually anything electrical is made from copper and not nickel silver.

Lastspikemike

where for some reason the rail joints aren't enough

An argument could easily be made for a layout in very well climate controlled conditions that busses and feeders are not necessary.  However, most if not all modelers don't have conditions such that prevent expansion and contraction of varying components of a layout.  I recall my previous layout, built in a basement, broken into sections or districts for troubleshooting purposes, but only single sets of feeders to each section.  Everything ran flawlessly.  Until it didn't.  I had very carefully connected each piece of track with TIGHT joiners to ensure continuity with no joints soldered.  Over time, expansion and contraction allowed rails to slide ever so slightly back and forth at one specific joint in my yard.  The movement resulted in the previously tight rail joiner loosening and failing to conduct power down half the yard (single ended yard, problem joint in the yard ladder).  The basement did not have large temperature or humidity swings, but what it did have was enough to cause an issue over time.  That's what modelers who have either been down this road or have listened to other's war stories are premptively addressing here.  Contrary to what one might think, the offending joiner was not an easy find for more reasons than what I feel explaining and taking this further off topic on the OP.

Lastspikemike

The question is: is a bus necessary? No it isn't.

Whether one answers this question as a yes or a no, it is totally an opinion formed on one's own experiences or exposure to other's experiences.  There was a time I would have agreed with this.  Then I experienced otherwise as noted above.  It's kind of like a defroster on a car.  Not necessary.  You could very well drive with your head out the window (ala Ace Ventura) if your windshield was fogged up.  A defroster provides an alternate path to a similar end.

Lastspikemike

By adding a parallel path for power with bus wires (of any gauge) you can also reduce voltage drop but only if the rails are conducting power also anyway.

Not sure what you are really trying to say here.  Are you suggesting you would have a bus and rails that do not conduct power (deadrail)?  Not much point in the bus then from my stance.  Rails being a poor conductor (including joints which can be troublesome) is what is behind voltage drop.  Copper experiences far less voltage drop, which is one way the bus helps.

Lastspikemike

Voltage drop is not usually a problem for a home sized layout. 

Correct, not usually.  I know I've read of some members having that problem though.  Many of us are of the stance that a bus is a simple to use, easy to implement during construction approach that doesn't cost much, and can eliminate issues related to continuity.

Now, I've typed a bunch.  Hopefully not for no gain.  I must offer my apology to the OP though.  He never asked if a bus was necessary.  He asked how terminal strips were used with one.

[gregc]

dtabor

Wondering what the advantage of a terminal strip is and how that works with feeders.

the terminal strip would join busses, not feeders.   or could be used to connect power districts to circuit breakers.

BATMAN

What gauge wire is equal to code 83 rail?

i've read the equivalent to 26g wire (0.041 Ohm/ft)

DigitalGriffin

You'll get a .3V drop  on that feeder.

yes, 5A thru a pair of 3ft 20g (0.010 Ohm/ft) feeders is 0.3V, but how likely are you to draw 5A and only thru one set of feeders?

aren't feeders typically 6", dropped thru the benchwork to a nearby bus.   and aren't there multiple feeders that the current low thru.

so for feeders (2 wire/paths) at each end of 6ft of track, the values for a loco in the middle of that track are

      track  0.246 Ohm,  3.0 ft, 0.041 (26g) Ohm/Ft
     feeder  0.010 Ohm,  0.5 ft, 0.010 (20g) Ohm/Ft
   one path  0.256 Ohm
   two path  0.128 Ohm
  volt drop  0.064 V @ 0.500A

and for 20 ft of (each direction) 16g and 18g bus

   bus drop  0.080 V 20ft 0.0040 (16g) Ohm/ft
   bus drop  0.128 V 20ft 0.0064 (18g) Ohm/ft

[DigitalGriffin]

 

 

You can see my bus with t-taps off to the right, and how they tie into the terminal strips.  This is my son's layout I built for him.