Date   

Re: Block detection/wheel set resistors

dsabourne
 

For my layout planning, I am planning on using optic detectors from Azatrax ... linked back into my Digitrax LocoNet.  My issue with detector is the lack of commercial available resistor wheelsets for my non-electric rolling stock.

Regards,
David Bourne


Re: Block detection/wheel set resistors

Brent Johnson
 

Wouter,
why would I need to have detection for every spur? A prototype CTC panel only lights up when a train occupies a block on the main or passing track. I don’t want the panel to show occupancy of a block just because a car with a resistor is spotted at an industry. 

Brent


Re: Block detection/wheel set resistors

Tim
 

On Thu, Sep 3, 2020 at 05:08 AM, whmvd wrote:
Yes for number 1. But I would not call what you describe for number 2 best practice. By a long way.
 
Ideally, there should not be any undetected trackwork at all. A spur should be at least one block. A turnout also. Yes, that is a lot of blocks. And a lot of detectors. And a lot of electronics to get the status for each block back into the command station.
My layout will include ABS signals (already has some on the parts I've built). For that there is no need for detection on anything but main tracks. If you want to monitor every track, which you might do if you're planning for remote ops, I can see doing what Wouter suggests.

I use the LCC stuff made by RR-CirKits. If you want to be ready to implement 100% detection, go ahead and add the current transformers to the leads to the spurs and solder the twisted pair wires to the transformers with enough lead to reach wherever you might put the detector. Better yet, make up a bunch of CT coils with 10 feet of twisted pair wire on the workbench The CT coils from RR-CirKits are $1.70 each (I'm sure you can find them cheaper), and the twisted pair wire (stripped out of CAT5 cable) is next to nothing. Add the twisted pair to the coils now so you don't need to try to do it later, when it will be much more difficult to get at. Finally, label everything. Your layout does not look the same on the bottom as it does on the top. :)


Re: Block detection/wheel set resistors

whmvd
 

Brent,

Yes for number 1. But I would not call what you describe for number 2 best practice. By a long way.

Ideally, there should not be any undetected trackwork at all. A spur should be at least one block. A turnout also. Yes, that is a lot of blocks. And a lot of detectors. And a lot of electronics to get the status for each block back into the command station.

If you have even the vaguest idea of wanting to use signals at any time in the future, do not skimp on blocks now.

At the very least, ensure the block boundaries exist, each with a separate feeder. That's a good first stage whichever path you choose later. After all, you can simply connect them under the layout until you want to progress to signalling. But if you don't do it now, the job will be a lot bigger later on.

Good luck
Wouter


On Thu, 3 Sep 2020, 00:25 Brent Johnson via groups.io, <Brntjh=aol.com@groups.io> wrote:
So to summarize the best recommended practices for reliable block detection suggested in this thread: 

1. Every car should be equipped with a resistor or something to draw power.
2. Isolate every spur track from the signal detection bus to avoid spotted cars from being detected.

Does this pretty much sum it up?
Brent Johnson


On Sep 2, 2020, at 6:41 PM, wirefordcc <bigboy@...> wrote:

Your system may only get confused if you have a big gap between your locos and your cars that have LEDs or lighted cars.  Ideally, block detection is best done with every car drawing some power to activate the block detection.

Allan Gartner
Wiring for DCC


Re: Block detection/wheel set resistors

AD
 

It says, when you are running on automatic and one train is following a first and somehow that wheel on the caboose loses detection you have a backup contact to delay the restart of the second train and lower the probability of a crash 

Tony


On Sep 2, 2020, at 7:48 PM, emrldsky <azMikeG@...> wrote:



Depends what you are doing... If you are using them for start and end of train detection, then what does the one in the middle say?

On 9/2/2020 3:38 PM, AD wrote:
Why nothing else with resistors?  What if the car in middle of train also has resistor wheels wont that just help detect the train?

Tony


On Sep 2, 2020, at 5:36 PM, emrldsky <azMikeG@...> wrote:



If you do do this, you will have to make sure that EVERY train you run has am engine and a caboose, and nothing else with resistors, but ALWAYS those two. Otherwise whatever computer program or logic that is used will easily get confused. There are software approaches to help sort out any confusion, but it gets really complicated. Plus Mr Murphy guarantees there will always arise one more situation you have not thought of.


Peace,

Mike G.


On 9/2/2020 11:21 AM, Brent Johnson via groups.io wrote:
just placing resistors on the caboose so the front and rear of train has detection


Re: Block detection/wheel set resistors

emrldsky
 

Depends what you are doing... If you are using them for start and end of train detection, then what does the one in the middle say?

On 9/2/2020 3:38 PM, AD wrote:
Why nothing else with resistors?  What if the car in middle of train also has resistor wheels wont that just help detect the train?

Tony


On Sep 2, 2020, at 5:36 PM, emrldsky <azMikeG@...> wrote:



If you do do this, you will have to make sure that EVERY train you run has am engine and a caboose, and nothing else with resistors, but ALWAYS those two. Otherwise whatever computer program or logic that is used will easily get confused. There are software approaches to help sort out any confusion, but it gets really complicated. Plus Mr Murphy guarantees there will always arise one more situation you have not thought of.


Peace,

Mike G.


On 9/2/2020 11:21 AM, Brent Johnson via groups.io wrote:
just placing resistors on the caboose so the front and rear of train has detection


Re: Block detection/wheel set resistors

AD
 

Why nothing else with resistors?  What if the car in middle of train also has resistor wheels wont that just help detect the train?

Tony


On Sep 2, 2020, at 5:36 PM, emrldsky <azMikeG@...> wrote:



If you do do this, you will have to make sure that EVERY train you run has am engine and a caboose, and nothing else with resistors, but ALWAYS those two. Otherwise whatever computer program or logic that is used will easily get confused. There are software approaches to help sort out any confusion, but it gets really complicated. Plus Mr Murphy guarantees there will always arise one more situation you have not thought of.


Peace,

Mike G.


On 9/2/2020 11:21 AM, Brent Johnson via groups.io wrote:
just placing resistors on the caboose so the front and rear of train has detection


Re: Block detection/wheel set resistors

Brent Johnson
 

So to summarize the best recommended practices for reliable block detection suggested in this thread: 

1. Every car should be equipped with a resistor or something to draw power.
2. Isolate every spur track from the signal detection bus to avoid spotted cars from being detected.

Does this pretty much sum it up?
Brent Johnson


On Sep 2, 2020, at 6:41 PM, wirefordcc <bigboy@...> wrote:

Your system may only get confused if you have a big gap between your locos and your cars that have LEDs or lighted cars.  Ideally, block detection is best done with every car drawing some power to activate the block detection.

Allan Gartner
Wiring for DCC


Re: Block detection/wheel set resistors

wirefordcc
 

Your system may only get confused if you have a big gap between your locos and your cars that have LEDs or lighted cars.  Ideally, block detection is best done with every car drawing some power to activate the block detection.

Allan Gartner
Wiring for DCC


Re: Block detection/wheel set resistors

Arthur Hammeke
 

Do leds and lighted coaches confuse block detection

Sent from my T-Mobile 4G LTE Device


From: w4dccqa@groups.io <w4dccqa@groups.io> on behalf of emrldsky <azMikeG@...>
Sent: Wednesday, September 2, 2020 4:36:17 PM
To: w4dccqa@groups.io <w4dccqa@groups.io>
Subject: Re: [w4dccqa] Block detection/wheel set resistors
 

If you do do this, you will have to make sure that EVERY train you run has am engine and a caboose, and nothing else with resistors, but ALWAYS those two. Otherwise whatever computer program or logic that is used will easily get confused. There are software approaches to help sort out any confusion, but it gets really complicated. Plus Mr Murphy guarantees there will always arise one more situation you have not thought of.


Peace,

Mike G.


On 9/2/2020 11:21 AM, Brent Johnson via groups.io wrote:
just placing resistors on the caboose so the front and rear of train has detection


Re: Block detection/wheel set resistors

emrldsky
 

If you do do this, you will have to make sure that EVERY train you run has am engine and a caboose, and nothing else with resistors, but ALWAYS those two. Otherwise whatever computer program or logic that is used will easily get confused. There are software approaches to help sort out any confusion, but it gets really complicated. Plus Mr Murphy guarantees there will always arise one more situation you have not thought of.


Peace,

Mike G.


On 9/2/2020 11:21 AM, Brent Johnson via groups.io wrote:
just placing resistors on the caboose so the front and rear of train has detection


Re: Block detection/wheel set resistors

Tim
 

There are a few possible solutions. (I didn't think of any of these.)

1- Put gaps in the spur tracks and connect the feeders to the power section bus, not the signal detection bus. This is what I'm doing.
2- As you suggest, detect the locomotives and cabooses only. The problem with this is that short sections (i.e. shorter than a typical train) would show clear when it's not. If you're doing CTC, most of your OS sections (like the turnout at the end of a siding) would fall into this category.
3- Put optical detectors at the block boundaries (I got this idea from Dick Bronson). Set it up so that if the optical detector is blocked it makes both track sections show occupied. This eliminates the problem described in #2, but is more work and cost, and you might not like the appearance of the optical sensors, which sort of have to be visible.

You can combine 2 and 3, and just use the optical detectors around the OS sections and other short sections. In either case it won't protect from a car that wanders out onto the main track by itself. I prefer number 1 and have all cars detectable.

Tim Rumph
Lancaster, SC


Re: Block detection/wheel set resistors

Bill Wilken
 

You've given me an idea.  Before testing again, I will remove every car/loco off the track.  


On Wed, 2020-09-02 at 11:21 -0700, Brent Johnson via groups.io wrote:

I am building a large layout that I am blocking for future CTC signaling. I know that it’s recommended to place resistors on wheels of freight cars to help detect the entire train and not just the engine or lighted cars. 

My first concern is that If many of the freight cars have resistors, wouldn’t the block show occupied if they are spotted on industrial spurs off the main or passing tracks? Obviously one way to get around this would be to isolate every spur from the detected block but that would be a lot of additional work.

To avoid the unwanted detection on spurs, could I get by with just placing resistors on the caboose so the front and rear of train has detection and not worry about additional freight cars being detected? Would that alone be sufficient to detect a train in a particular block?

Thanks,
Brent Johnson


Block detection/wheel set resistors

Brent Johnson
 

I am building a large layout that I am blocking for future CTC signaling. I know that it’s recommended to place resistors on wheels of freight cars to help detect the entire train and not just the engine or lighted cars. 

My first concern is that If many of the freight cars have resistors, wouldn’t the block show occupied if they are spotted on industrial spurs off the main or passing tracks? Obviously one way to get around this would be to isolate every spur from the detected block but that would be a lot of additional work.

To avoid the unwanted detection on spurs, could I get by with just placing resistors on the caboose so the front and rear of train has detection and not worry about additional freight cars being detected? Would that alone be sufficient to detect a train in a particular block?

Thanks,
Brent Johnson


Weird signal behavior

Bill Wilken
 

I have just begun an effort to equip my entire railroad with Atlas
signals driven by NCE BD-20 block detectors. The railroad is powered
by a NCE PowerCab and PowerPro booster.

I created my first signal block within a considerably longer power
district. When I run an Athearn GP-9 or a BLI Blueline F7 in and out
of the signal block, the signal works properly, showing red when the
block is occupied and green when it is empty. So far so good.

But when I run larger locos like a BLI E8 or a Rapido FA-2 (consisted
or not), the signal is always red whether the loco is in or out of the
block but within the surrounding power district. Once the loco moves
to another power district, the signal turns green.

Importantly the rails within the 40'-long signal block are all properly
gapped. After first getting the anomalous result when I put several
signal bus drops through the BD-20, I decided to try only one drop, and
the signal continued to operate in the same fashion. Similarly, for
testing purposes, I'm powering Atlas signal control board with nothing
but a 9-volt battery. I've not yet tried adding a 500 Ohm resistor to
the BD-20, but it's not clear to me why that would help.

I welcome any clues that might lead to a fix for this problem.


Re: wiring Pm42 using Accu-lite

Jerry Michels
 

I think using the Acculite beadboard is a great choice.  As to wiring, the Digitrax diagram is pretty straight forward.  For power management, you run the two wires from a block to the PM42 input terminals for a given block and then two wires from the same-numbered output to your command station DCC output.  Since you are intent on multiple blocks, you can have a common pair of wires that you connect to your Command Station power output.  This is called a power buss.  We find that a single buss will handle about eight blocks.  The reverse  loop works in a similar manner with the exception that you need to 'tell' the PM42 that a specific input is a reversing loop.  

Jerry Michels
Amarillo Railroad Museum


wiring Pm42 using Accu-lite

Rrickster
 

I have a HO scale digitrax system. I would like to use the Pm42 for 
1) power management
2) reverse loop
I wanted to avoid soldering so I am using Accu-lite breakout boards. I am having a difficult time accomplishing both tasks. Does anyone have aI have a HO scale digitrax system. I would like to use the Pm42 for 
1) power management
2) reverse loop
I wanted to avoid soldering so I am using Accu-lite breakout boards. I am having a difficult time accomplishing both tasks. Does anyone have a wiring schematic or could instruct me on how to accomplish these tasks. 
 
 
 
 
ReplyForward
or could instruct me on how to accomplish these tasks. 
 
 
 
 
ReplyForward


Re: Atlas signal - Tortoise Interlocking

wirefordcc
 

If there is a resistor between the Tortoise and signal, that may be because the Tortoise may being used to drive an LED directly.  That isn't an issue with the Atlas SCB.


Re: Atlas signal - Tortoise Interlocking

Bill Wilken
 

Alan,

Many thanks.  Actually, I do want the switch machine to provide input ... exactly as you suggest.

On a number of schematics I've seen showing Tortoises connected to signals, the schematic shows a resistor between the signal and Tortoise.  But given that the Atlas signal control board can handle up to 12 volts, I'm guessing that shouldn't be an issue.

I'm all set on switch motor wiring.  Thank heaven for the availability of SMAILs.  The small added charge for the DCC control chip on the switch motor is worth every penny.  

On Wed, 2020-08-05 at 11:29 -0700, wirefordcc wrote:
Hi Bill,

I reviewed the Atlas schematic you supplied and also went the Atlas website to learn a little bit about the Atlas Signal Control Board (SCB).  I found that it does not control the Atlas switch machine or Tortoise as you desire.  Rather, the Atlas switch machine or a Tortoise provides input to it.

The blue wire you see on the Atlas schematic that goes to the common on the Atlas switch machine would be attached to terminal 4 on a Tortoise.  The two green wires shown going to the Atlas switch machine go to terminals 2 and 3 on the Tortoise.  If you get the wrong aspect displayed, swap the wires going to 2 and 3.

You can control the Tortoise with DCC via an accessory decoder like made by NCE or Digitrax or through any traditional means of controlling a Tortoise switch machine. For more on controlling Tortoise switch machines, visit my website at:  http://www.wiringfordcc.com/sw_ctl.htm

Allan Gartner
Wiring for DCC


Re: Atlas signal - Tortoise Interlocking

wirefordcc
 

Hi Brian,

Loading them into the photos and files section is easy, too, and doesn’t spread viruses to the computers of group members.  The administrators of this forum talk about it every so often and we still don’t want anyone’s computer to be adversely affected.

 

Allan

 

From: w4dccqa@groups.io <w4dccqa@groups.io> On Behalf Of Brian Lewis
Sent: Wednesday, August 05, 2020 11:59 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Atlas signal - Tortoise Interlocking

 

May I enquire why not please?  Surely attachments are the quickest and easiest way to demonstrate you problems/solutions.

On 05/08/2020 13:45, wirefordcc wrote:

Hi Bill,

This group does not handle attachments. 

Allan Gartner
Wiring for DCC

--

Regards and thanks

 

Brian Lewis