Droppers to bus


John DeSantis
 

Hi all. I.m a complete novice to dcc. My question is; on a layout with two separate loops, can you connect two droppers, from the outside rails together before conneccting them to the main bus? I have a diagram but I don't know how to upload it.


Tim
 

jdssr, As long as the drops are short that's fine.

Tim Rumph
Lancaster, SC


John DeSantis
 

Thanks Tim for your reply. Would you please elaborate on what  you mean by short. Do you mean the distance from the track to where the dropers are connected to each other (Point A) or the overall distance from the track to the bus (Point B).

John

On 03/18/2022 9:06 AM Tim <tarumph@...> wrote:


jdssr, As long as the drops are short that's fine.

Tim Rumph
Lancaster, SC


Tim
 

Usually drops are smaller wire than the main power bus. For instance, the main power bus on my layout is 12 AWG. The drops that are soldered to the rails are 22 AWG. I try to keep my drops less than 12 inches from the bus to where it's soldered to the rail.

Tim


PennsyNut
 

May I make a suggestion based upon what "I think" you might be wanting to do? If you are talking about two tracks side by side, such as 2" between them, your little wires are going to be about 2". Therefore, what TimR said is right. I've done exactly that and used 22 AWG. No problems. So, it you are talking about more distance/more than 2", that's when you have to think about the wire size. The 22 AWG should be sufficient up to 10". More than that, go to 20 AWG. Or thereabouts. Hope this helps.
Morgan Bilbo, DCC since 8/18. Model PRR 1952.


John DeSantis
 

Thanks Morgan. I am in fact using 20AWG wires. 



Sent from my Verizon, Samsung Galaxy smartphone


-------- Original message --------
From: PennsyNut <fan4pennsy@...>
Date: 3/18/22 12:08 PM (GMT-05:00)
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Droppers to bus

May I make a suggestion based upon what "I think" you might be wanting to do? If you are talking about two tracks side by side, such as 2" between them, your little wires are going to be about 2". Therefore, what TimR said is right. I've done exactly that and used 22 AWG. No problems. So, it you are talking about more distance/more than 2", that's when you have to think about the wire size. The 22 AWG should be sufficient up to 10". More than that, go to 20 AWG. Or thereabouts. Hope this helps.
Morgan Bilbo, DCC since 8/18. Model PRR 1952.


Jerry Michels
 

I am not trying to stir the pot, but we have used both AWG 20 and 22 stranded wire for drops that are over a foot long, depending on the specific location/situation. We use either AGW 12 or 14 for buss wiring (modified extension cords). For over six years these drops have operated flawlessly. We can reliably deliver power to six sound-equipped locomotives per block without problems. If we get over six sound-equipped locomotives in a given block, there is a problem with in-rush current after a derailment; the locomotives will not always reset. Not good form during an open house. This is something we can easily avoid if our members are up to snuff when running trains.

I should mention that we prefer to run our busses in a chase at roughly chest level. A lot of us are starting to have trouble soldering drops to busses while lying on our backs under the layout and dodging molten drops of solder. In some cases, especially large towns with a lot of sidings, we bring the drops together to a terminal block and them to the buss.

My thought is that it is important to 'stress test' a given block to determine its limits. No doubt that drops should be kept as short as possible, but sometimes the drops should be kept as short as 'feasibly' possible.

Jerry Michels
Amarillo Railroad Museum
www.amarillorailmusuem.com


PennsyNut
 

I know I'm going to stir this up, but: When I started to try to understand how to wire my layout, I was totally confused about wire size. I did have an abundance of the cable that has 8 wires inside the insulation. When I stripped that insulation off, there were 8 wires with all different colored insulation on each wire. I used my strippers to determine that these wires were 20 AWG. I then asked online about the bus. Of course, everyone said 14 or 12. In previous use, I found them to be difficult to use. Too stiff? So, I then had someone explain to me about how to calculate wire size based upon expected usage. And we discovered that I could use 20 AWG for all. So, I did that. One wire for each feeder location and each rail. So, what this means is that I wired the two wires/18 AWG from the command station to a screw terminal block. And a single wire from that block to each rail. The maximum wire is 10'. And there are 16 of them. In 2 yrs now, I have had no trouble whatsoever. So, a bus don't have to be one wire - in my case, it's 16 wires. All 20 AWG. And my layout passes the quarter test. The electrical conductivity is constant, 15 v at each end and at the command station. (Well, actually 14.9, 15 & 15.1. But you get the point.)  So all I can say is for you to do the calculation based upon expected usage. (Finally, there's never been any heat build up. Never any shorts - other than what I created by accident. And I use a simple auto bulb/12v for the short indicator. That has worked great. Whenever I do cause a short, that bulb lights up and I can immediately fix it.)
Morgan Bilbo, DCC since 8/18. Model PRR 1952.


John DeSantis
 

Thank you for your responce Jerry. I now have a clear understanding of what to do. It seems there is more than one way to skin this cat.
John D

On 03/19/2022 10:43 AM Jerry Michels <gjmichels53@...> wrote:


I am not trying to stir the pot, but we have used both AWG 20 and 22 stranded wire for drops that are over a foot long, depending on the specific location/situation. We use either AGW 12 or 14 for buss wiring (modified extension cords). For over six years these drops have operated flawlessly. We can reliably deliver power to six sound-equipped locomotives per block without problems. If we get over six sound-equipped locomotives in a given block, there is a problem with in-rush current after a derailment; the locomotives will not always reset. Not good form during an open house. This is something we can easily avoid if our members are up to snuff when running trains.

I should mention that we prefer to run our busses in a chase at roughly chest level. A lot of us are starting to have trouble soldering drops to busses while lying on our backs under the layout and dodging molten drops of solder. In some cases, especially large towns with a lot of sidings, we bring the drops together to a terminal block and them to the buss.

My thought is that it is important to 'stress test' a given block to determine its limits. No doubt that drops should be kept as short as possible, but sometimes the drops should be kept as short as 'feasibly' possible.

Jerry Michels
Amarillo Railroad Museum
www.amarillorailmusuem.com



John DeSantis
 

Thank you for your responce Morgan. I now have a clear understanding of what to do. It seems there is more than one way to skin this cat.
John D

On 03/19/2022 12:32 PM PennsyNut <fan4pennsy@...> wrote:


I know I'm going to stir this up, but: When I started to try to understand how to wire my layout, I was totally confused about wire size. I did have an abundance of the cable that has 8 wires inside the insulation. When I stripped that insulation off, there were 8 wires with all different colored insulation on each wire. I used my strippers to determine that these wires were 20 AWG. I then asked online about the bus. Of course, everyone said 14 or 12. In previous use, I found them to be difficult to use. Too stiff? So, I then had someone explain to me about how to calculate wire size based upon expected usage. And we discovered that I could use 20 AWG for all. So, I did that. One wire for each feeder location and each rail. So, what this means is that I wired the two wires/18 AWG from the command station to a screw terminal block. And a single wire from that block to each rail. The maximum wire is 10'. And there are 16 of them. In 2 yrs now, I have had no trouble whatsoever. So, a bus don't have to be one wire - in my case, it's 16 wires. All 20 AWG. And my layout passes the quarter test. The electrical conductivity is constant, 15 v at each end and at the command station. (Well, actually 14.9, 15 & 15.1. But you get the point.)  So all I can say is for you to do the calculation based upon expected usage. (Finally, there's never been any heat build up. Never any shorts - other than what I created by accident. And I use a simple auto bulb/12v for the short indicator. That has worked great. Whenever I do cause a short, that bulb lights up and I can immediately fix it.)
Morgan Bilbo, DCC since 8/18. Model PRR 1952.


thomasmclae
 

We actually do not solder anything on the club layout except for track drops and inside control panels.
All wires drop to spade lugs and a small terminal block.
20 Gauge solid wire for soldering to rails.
16 gauge to module buss, 18-guage for main bus from boosters around the layout.

Our section (module) count is 46. ( some city sections do not have mainline track)
NO issues with power anywhere on the layout.

Likely because each section is 4-8 feet long, and 18 gauge between sections.

Thomas
DeSoto, Tx


PennsyNut
 

Perhaps I should clarify some of what I did. The wires from the command station to the terminal block are 18 AWG, and are simply screwed to the TB. From there, the wires are 20 AWG all the way to the front of the layout, near where the feeders are. They are then connected to feeders by WAGO's. Then the feeder/20 AWG go to the track where they are soldered. So the only soldering I had to do was to the rails. And the connections to WAGO and the TB are physical, but extremely solid. I see no way for them to fail - You can tug on them. As well as tugging on the solder joints. Hope this clarifies some. I'm not afraid of soldering, and can do so with confidence. It's just that I wanted an easier way to fix any problems. And so far, in over 2 yrs, no problems anywhere with wiring.
Morgan Bilbo, DCC since 8/18. Model PRR 1952.


Don Weigt
 

PennsyNut,

Your wiring method clearly is working for you so far. That's great. I like your mention of tugging. I'm a believer in the "tug test", at appropriate forces for each connection being tested.

Not soldering under the layout sure would be welcome. I soldered all my stuff, most of it 30 years ago. It was hard then. It's getting harder for me to do now, as I rebuild my layout after a move.

Mechanically made electrical connections not subject to a lot of flexing are more likely to fail over long periods of time, not short, due to corrosion or surface oxidation. Using good quality connectors and methods is your best protection against that.

You probably know that the telephone companies were pioneers of solderless connections. They found properly made solderless connections were more reliable than soldered ones. "Properly made" is critical. Enough contact pressure is required.

The contacts need to cut into the wires and create a tiny metal to metal contact zone sealed against air and oxygen, because long term failures usually are the result of oxidation of the metal at the joints. Surface oxidation insulates the wires from one another, especially in damp or other corrosion prone environments. Oxidized metals become insulators.

You'll learn how good your connections really are over the next 20 or 30 years. If they stay trouble free, then they are really good. If you begin having problems, they aren't. So, it's important that you are doing a quality job now. It's to your long term benefit.



--
Don Weigt
Connecticut


Jerry Michels
 

Don, you said it well. There may be many ways to make connections, but the key is to do it right the first time! This is the best anti-gremlin dust there is. Jerry Michels