Relays for Track Power using AIU

Stan, that’s exactly what I want to do. Having 4 or 5 engines power up when I apply power to a set of sidings can be a little unnerving.

John, even with the modified DCSRC, will I be able to control the individual engines from the TIU remote. If that’s the the case, then that’s what I need. I’m willing to try making one of the piggy back boards. (What could possibly go wrong?)

I still cannot believe that it did not occur to MTH that this would be a ‘must have’ option.

where do I go from here?

gunrunnerjohn posted:

Sounds like George really needs a couple of the A&T Perpetual Barking Watchdog boards to equip a couple of DCSRC units.

Agreed.  BUT I believe procuring a resistor here, a capacitor there, messing with bare circuit-boards, soldering, testing, etc. can be a hurdle for a lot of guys.

Soooo...here's my latest hare-brained scheme.  This uses $2 (free shipping from Asia) eBay "Delay-OFF" relay modules.  You need one Delay-OFF relay module per siding.  But one unmodified (stock) DCSRC receiver can serve multiple sidings.

Here's the idea.  A Delay-OFF relay module turns on for some fixed settable period, then it turns OFF.  So when power is applied to a particular siding using the existing external relay module, a paired Delay-OFF relay also turns on for, say, 5 seconds.  The Delay-OFF relay module momentarily (for 5 seconds or whatever) attaches the DCSRC to the newly powered siding.  The DCSRC generates its "watchdog" signal to the newly powered siding.  The Delay-OFF relay module then turns off (after 5 seconds)...but track power is still applied to the siding since the main power relay is still ON as controlled by the ACC port.

So after 5 seconds, the DCSRC is disconnected and turned OFF.  This means the DCSRC is ready to be paired to an additional siding that gets powered ON.  Thus, one DCSRC can service multiple sidings...AND multiple sidings can be active!

I realize this is all getting somewhat convoluted but this is a discussion forum to share ideas. 

That sounds workable. So, both relays (power and DCSRC) will fire simultaneously and, hopefully, the watchdog signal will hit the engine in time to prevent it powering up on its on?

Sooo, is this the plan?

Correct.  When you press "ON" for a particular ACC port, two relays turn ON.  Like you say, the "power" relay applies power to the selected siding.  At the the same time the paired "DCSRC" relay connects the DCSRC-receiver to the newly powered siding.  The DCSRC-receiver generates the watchdog signal within 1 second of receiving power (then it goes idle and does nothing more).  Because the DCSRC relay is a Delay-OFF type, it will disconnect from the newly powered track after 5 seconds (or whatever you set the delay time).  The siding still has power since the "power" relay is still on.  

The DCSRC-receiver is now unpowered and disconnected from any siding...which means it is available to pair with another or additional "power" relays to supply the watchdog to other sidings.

Comparing/contrasting this new configuration relative to that using the modified DCSRC can be confusing but here goes.  The following diagram is from the long thread where the modified DCSRC (a.k.a. Perpetual Barking Watchdog) was born.

In this configuration, the DCSRC is always powered.  Remember that the DCSRC generates a single watchdog when it first gets power.  The modification alters the DCSRC behavior so it generates a watchdog about once per second as long as it receives power.  Then, whenever a siding is turned on, that siding will receive a watchdog within a second which keeps any newly powered engine silent and shutdown.

As to what's "the plan", I don't know of anyone who has implemented the scheme using an unmodified DCSRC with multiple Delay-OFF relays.  I just came up with it after pondering the pitfalls and landmines of assembling circuits at the component level.

And in the interest of completeness, here's yet another method that does NOT require the modified DCSRC.  

For less than $5 (free shipping from Asia), you can get a multifunction timer relay module that runs off of 12V DC.  12V DC is already available.  The multifunction timer can be set to turn ON for exactly 1.00 seconds, then turn OFF for exactly 0.10 seconds, and cycle ON-OFF forever.  By inserting the modules relay contacts as shown above (breaking the connection to the DCSRC), an unmodified DCSRC will receive power for exactly 1.0 seconds which is enough time for it to generate the watchdog.  Then it is briefly powered down (for 0.1 sec) then re-powered so that it again generates the watchdog.  Lather, rinse, repeat.

So this method would only require 1 multifunction timer module to service multiple sidings in a yard.  There are probably even less expensive cycling relay modules but I happen to have the above relay module and know it will do the job.

This module is constantly clicking ON-OFF thousands of times per hour.  Click-click-click...  but maybe it's under the table and inaudible.  The PBW modification essentially does the same thing except no moving parts.

I recognize that recycled drawing!

Since I already have a 4 relay board. I am going to try “plan A” that requires multiple delay off boards and one DCSRC. I found the attached delay off boards on eBay that have an adjustable time off setting. Wil this board work?

Despite the listing wording, that's a Delay-ON relay module (instead of a Delay-OFF).   So you apply 12V to the input, the relay waits a settable time delay, then the relay turns ON.  For the application under discussion, you want a Delay-OFF.  So you apply 12V to the input, the relay immediately turns ON (attaches DCSRC to siding), then waits a settable time delay, then the relay turns OFF (detaches DCSRC from siding). 

I have both types of these Delay relay modules.  Both have applications in O-gauge. 

Speaking of "patience"... I paid $1.26 each (free shipping) for the Delay-OFF module.  I paid $0.77 each (free shipping) for the Delay-ON module.  Prices move around.  Go figure!

stan2004 posted:

And in the interest of completeness, here's yet another method that does NOT require the modified DCSRC.  

For less than $5 (free shipping from Asia), you can get a multifunction timer relay module that runs off of 12V DC.  12V DC is already available.  The multifunction timer can be set to turn ON for exactly 1.00 seconds, then turn OFF for exactly 0.10 seconds, and cycle ON-OFF forever.  By inserting the modules relay contacts as shown above (breaking the connection to the DCSRC), an unmodified DCSRC will receive power for exactly 1.0 seconds which is enough time for it to generate the watchdog.  Then it is briefly powered down (for 0.1 sec) then re-powered so that it again generates the watchdog.  Lather, rinse, repeat.

So this method would only require 1 multifunction timer module to service multiple sidings in a yard.  There are probably even less expensive cycling relay modules but I happen to have the above relay module and know it will do the job.

This module is constantly clicking ON-OFF thousands of times per hour.  Click-click-click...  but maybe it's under the table and inaudible.  The PBW modification essentially does the same thing except no moving parts.

Stan, I just ordered two of this module. it will be arriving by a slow boat from China. Soooo, you'll be hearing from me again in the future. In the meantime, I have to search for a command module. Its been a long time since I last read a circuit diagram. At the top of your diagram. do you have a rotary switch there that cycles between the sidings? Or does that indicate a switch that is dedicated to one siding. That is, one switch for each siding.

Really appreciate the help that I am getting with everyone on this. Its going to be a sweet setup!

Stan,

I am interested in your "hare-brained scheme" with an unmodified DCSRC connected to some Delay-OFF relays. I just have a couple of questions:

1) Is it okay for the hot inputs to come from a TIU channel that is wired in the normal fashion with transformer power coming through the TIU (i.e. not in passive mode)?

2) I'm guessing that a choke is not needed in this setup. Is that correct?

Thanks.

John

George Mason posted:

...At the top of your diagram. do you have a rotary switch there that cycles between the sidings? Or does that indicate a switch that is dedicated to one siding. That is, one switch for each siding.

That diagram is based on GRJ's original proposal to silence DCS engines on a newly powered yard siding.  In his case a manual rotary-switch selects one siding from many.  In your case you are using the AIU in conjunction with external relays to select one siding from many; and you can power up any or all of the sidings at any given time.  The thread is a very long winding road which ended up with the modified-DCSRC.  GRJ was proposing a perfectly functional method; I proposed an alternative and built a proof-of-concept thinking it would be a one-off.  But somehow it gained traction and the rest is history; circuit boards were made, kits were offered, etc. 

So the latest plan is to use the cycling relay module?  So 1 x $5 cycling module to handle a 5-siding yard...rather than 5 x $2 Delay-OFF modules for a 5-siding yard.  Of course you still need the (unmodified) DCSRC-receiver.  It may actually turn out that a single cycling module (and single DCSRC-receiver) can handle BOTH of your 5-siding yards.  This will kind of depend on the size of the layout and how far apart your two yards are from each other.  But we can explore that when you get closer to construction - and the wiring will NOT be much different.

johnf posted:

I am interested in your "hare-brained scheme" with an unmodified DCSRC connected to some Delay-OFF relays. I just have a couple of questions:

1) Is it okay for the hot inputs to come from a TIU channel that is wired in the normal fashion with transformer power coming through the TIU (i.e. not in passive mode)?

2) I'm guessing that a choke is not needed in this setup. Is that correct?

1.  Yes.  

2.  That's what I think.  I believe the high-current choke shown in the GRJ's diagram has to do with operating a TIU in passive-mode with a PSX-AC breaker.  But you're running the TIU in normal fashion.

Thanks!

Thanks for your response Stan.

Correct, I was running the TIU in passive mode.  Actually, it's my preferred mode of operation, I've discovered that if I use a choke between the transformer and the track, there is no measurable signal strength difference between passive and active mode.

Barry Broskowitz posted:

 Ok, that makes sense. I am surprised that MTH hasn’t marketed a solution to this issue.

You may call this an “issue”, however, It’s not actually a problem. The AIU is designed and intended to operate switch tracks and accessories, not engines.

Barry,

This has nothing to do with the above text. I was trying to help someone out with his MTH Wi-Fi and since you wrote the book you on it, I am writing to you.  

1] What are the issues associated with not having a Wi-Fi unit connected to the internet via a wired connection or home Wi-Fi?

2] if not connected to the internet, what errors would one see when trying to add an engine?

I guess that I’m going to eventually buy a Wi-Fi unit to run my trains. Is there a second edition of the Wi-Fi bible under development?

Thanks for the help!

George

George,

1] What are the issues associated with not having a Wi-Fi unit connected to the internet via a wired connection or home Wi-Fi?

The only issues are that you would be unable to access other WiFi devices on your home network or use any of web-based commands in the DCS App to access MTH web pages.

2] if not connected to the internet, what errors would one see when trying to add an engine?

There’s no difference when adding engines with or without Internet access.

I guess that I’m going to eventually buy a Wi-Fi unit to run my trains. Is there a second edition of the Wi-Fi bible under development?

The 2nd edition of The DCS WiFi Companion was published this past March.

Barry,

How does the wifi unit determine if the engine on the track is supported? It must have a database somewhere that IDs the train and its features. Or is that updated when new releases of the firmware are issued?

I have your other DCS book in Kindle format. Ill have to check again and see if the wifi book is available.

Thanks,

George

George,

How does the wifi unit determine if the engine on the track is supported? It must have a database somewhere that IDs the train and its features. Or is that updated when new releases of the firmware are issued?

Everything that DCS needs to know about the engine, is already in the engine.

As you await the multifunction cycling relay module, here's some additional background.  You can google FRM01 which is the model number and get dozens of youtube videos on how to use it.  There are instructions but the original translation was virtually incomprehensible translation and DIY'ers have taken it upon themselves to re-write it.  Attached is what I think is a pretty good version.

You want to set the module to Function Mode 06 with parameters as shown.  This will make more sense once you have the module in-hand and review the Instructions.

The FRM01 will apply track power to the (unmodified) DCSRC for 1.0 seconds, the watchdog will be generated, then power is removed for 0.1 seconds, then cycles forever.  

Here it is in action.  You can hear the relay clicking on and off.  You can see the green LED on the DCSRC turn ON for 1.0 seconds, then briefly turn OFF for 0.1 seconds.

The relay cycles ON-OFF, and the DCSRC cycles ON-OFF as longs as 12V DC power is applied....even if NO sidings are active.  The wiring configuration might be something like:

Perhaps you can't see/hear the cycling module in a noisy train room but it was driving me nuts just in the few minutes I was taking the video!  So for 1 penny per siding, here's a suggested modification that turns on the cycling ONLY if one (or more) sidings is actually powered on by an AIU ACC port.

The added diodes (one per siding installed as shown) turn on the FRM01 module only if a siding is active!  This has the benefit of reducing wear-and-tear on the electro-mechanical relay contacts cycling thousands of times per hour.  I suggest the common 1N4003 diode which is a useful component to have around for a variety of O-gauge DIY projects - very inexpensive.

Stan! This is great. I picked up two of the DCSRCs for $25 and I’m waiting for the circuit board.  I’ve been looking for wiring distribution connectors so that I can straighten out the mess of spaghetti that I created while getting the original relays working. Any suggestions? What amperage load do I need to address?

The switched track-voltage wires on the right side of the diagram (connected to the relays) carry whatever current your yard siding(s) carry.  So maybe 5 Amps max - note that you trains should not be zooming around in a yard.  The control signal wiring from the AIU to the relay modules carry 10 to 100 times less current.  I figure you're using, say, AWG 14/16 wiring for mainline track.  The control signals can be AWG 24/26.  Practically speaking you're probably buying the heavy wiring in spools so just use that.  And you can get good deals on spool of multi-conductor 24/26 wiring used for alarms, sprinklers, telecom, whatever. 

There is nothing particularly tricky about this wiring that would make the distribution method best suited to a specific connector type or scheme. 

Stan,

You’re right, no one will be rushing around the yard. Just for my own practice, I am controlling two loops and one siding with the AIU.  I have an older MTH Premuer Baldwin shark that someone converted to PS2 to PS3 for me. I’ve been running it in the larger loop and after a while (5-10 minutes), the circuit breaker in my ZW goes off and shuts down everything. Even with jusg that loop powered up. I have a 15 circuit breaker betwen the ZW and the tracks, it does not go off.  I’m thinking that I have a bit of a short inside the shark.

But, the reason I asked about track amperage is that I found some connector blocks that appeal to me. They have an amperage rating of 6 amps. (See the photo) I’m thinking that they should be fine fir the distribution of power.

Thanks,

George

Stan,

You’re right, no one will be rushing around the yard. Just for my own practice, I am controlling two loops and one siding with the AIU.  I have an older MTH Premuer Baldwin shark that someone converted to PS2 to PS3 for me. I’ve been running it in the larger loop and after a while (5-10 minutes), the circuit breaker in my ZW goes off and shuts down everything. Even with jusg that loop powered up. I have a 15 circuit breaker betwen the ZW and the tracks, it does not go off.  I’m thinking that I have a bit of a short inside the shark.

But, the reason I asked about track amperage is that I found some connector blocks that appeal to me. They have an amperage rating of 6 amps. (See the photo) I’m thinking that they should be fine fir the distribution of power.

Thanks,

George

Here’s a photo of the layout:

Each track is powered on through the AIU. The siding, with the two engines, is receiving a wake up signal from the little  MTH controller. Success! Neither engine starts until I issue the startup command in the remote. 

I know that the wiring looks bad but it’s a 100% improvement over the original rates nest. Can I use the same DCSRC to issue wake up signals for the other two tracks?

Thank you for all the help!

George Mason posted:

 

... Can I use the same DCSRC to issue wake up signals for the other two tracks?

Not sure I understand the question.  In your photo it appears everything (both loops and the siding) are powered by the TIU Fixed-1 output.  The DCSRC provides the watchdog signal to silence any engines on the siding when the siding is turned on.

Since the two loops are always directly connected/powered to the Fixed-1 output, they will have received the watchdog when the TIU Fixed-1 was initially turned on.  What am I missing? 

You are missing the relays between the AIU and the two loops and one siding. They are powered up after the AIU and as a result, no watchdog signal. The DCSRC provides the watchdog signal when the relay is activated by the AIU.

I think I get it.  Above diagram reflects your "test" layout.  Inner loop, outer loop, and siding are each independently powered by an AIU ACC output.

So this is kind of like a 3-siding configuration...except 2 of the sidings are just your inner and outer loops.

I take it your DCSRC is "merrily" clicking away about once per second?

It could be. I haven’t listened to it carefully. The only reason that I set up the two loops as sidings was to learn the ins and outs of the relays and the little control box. It’s really slick! Makes me feel like I am in control of (some) things!

One more question....what gauge wire do you all use 14 or 16? Stranded or solid? And what’s your feelings about using the power bricks?

Could not have done it without your and John’s help. Now I can start planning the real thing!

Thanks again!

George

George Mason posted:

...

One more question....what gauge wire do you all use 14 or 16? Stranded or solid? And what’s your feelings about using the power bricks?

That's 3 questions!  

You're better off asking these questions in a separate thread in that the issues of configuring the AIU, relays, DCSRC, etc. for the application of silencing DCS engines on power-up are essentially independent of the type of wiring and power source.

Will do

stan2004 posted:

I think I get it.  Above diagram reflects your "test" layout.  Inner loop, outer loop, and siding are each independently powered by an AIU ACC output.

So this is kind of like a 3-siding configuration...except 2 of the sidings are just your inner and outer loops.

I take it your DCSRC is "merrily" clicking away about once per second?

Stan, I noticed that you indicate the power coming from the "Fixed 1 output".  Early on, for some reason, I opted for the variable output.  I am having some difficulty wiring the relays and the DCSRC in the manner that you show in the above diagram. No matter what I do, the engine on the siding powers up in conventional mode when I turn on the power for the siding. I am also not sure how to program the intermittent relay. Any help is appreciated.

stan2004 posted:

I think I get it.  Above diagram reflects your "test" layout.  Inner loop, outer loop, and siding are each independently powered by an AIU ACC output.

So this is kind of like a 3-siding configuration...except 2 of the sidings are just your inner and outer loops.

I take it your DCSRC is "merrily" clicking away about once per second?

The DCSEC does not appear to be doing anything, Should either of the DCSRC lights be on?  I checked the wiring again and again.  I may not have the intermittent relay programmed correctly. 

Should be no problem using a VAR channel instead of a FIXED. But, if given a choice, I'd just use FIXED 1.  Especially in what I believe is your end configuration of just ONE DCS channel powering your 2 loops and 1 siding.

Anyway, are you saying you can't get the FRM01 timer module to cycle on and off as shown in the video?  This is a matter of programming the FRM01 (which I acknowledge can be tricky) using the PDF instructions I attached in a previous post.  You don't even need the DCSRC attached to see if the FRM01 is "working".  When programmed correctly to Function 6 it will merrily click (and on-board LED flashes) - 1 second on, 0.1 seconds off.  

stan2004 posted:

Should be no problem using a VAR channel instead of a FIXED. But, if given a choice, I'd just use FIXED 1.  Especially in what I believe is your end configuration of just ONE DCS channel powering your 2 loops and 1 siding.

Anyway, are you saying you can't get the FRM01 timer module to cycle on and off as shown in the video?  This is a matter of programming the FRM01 (which I acknowledge can be tricky) using the PDF instructions I attached in a previous post.  You don't even need the DCSRC attached to see if the FRM01 is "working".  When programmed correctly to Function 6 it will merrily click (and on-board LED flashes) - 1 second on, 0.1 seconds off.  

 

Yes it’s clicking merrily! And I programmed F6 as you specified. However the engine on the isolated track starts up in conventional mode. The DCSRC keeps on clicking after the power to the track is disconnected.

George Mason posted:

stan2004 posted:

Should be no problem using a VAR channel instead of a FIXED. But, if given a choice, I'd just use FIXED 1.  Especially in what I believe is your end configuration of just ONE DCS channel powering your 2 loops and 1 siding.

Anyway, are you saying you can't get the FRM01 timer module to cycle on and off as shown in the video?  This is a matter of programming the FRM01 (which I acknowledge can be tricky) using the PDF instructions I attached in a previous post.  You don't even need the DCSRC attached to see if the FRM01 is "working".  When programmed correctly to Function 6 it will merrily click (and on-board LED flashes) - 1 second on, 0.1 seconds off.  

 

Yes it’s clicking merrily! And I programmed F6 as you specified. However the engine on the isolated track starts up in conventional mode. The DCSRC keeps on clicking after the power to the track is disconnected.

I had the wires on the track relay reversed all is well. Now, how do I stop that annoying clicking?

There are (at least) 4 alternatives to the annoying perpetual clicking.

1. Earplugs.

2. The original modified DCSRC, a.k.a. Perpetual Barking Watchdog.  No moving parts (no relay) so no clicking.

3. Use one Delay-OFF relay module for each loop or siding that's under relay control.  The Delay-OFF module will turn on (one click) the DCSRC for 1 second when power is first applied to the loop or siding.  The DCSRC generates the watchdog to silence the engine(s) on that newly powered section.  Then 1 second later the DCSRC turns off (a 2nd click) and stays off and silent no matter how long that section remains powered.  A diagram of this was shown in the post of 5/7.

4. Use one diode per loop or siding to only power the FRM01 when one (or more) loop or siding is actually powered.  So if no loop or siding is powered, the FRM01 is off and silent.   A diagram of this was shown in the post of 5/11.   But to be clear, you'll hear the clicking sound as long as one (or more) loops or sidings are active.

I think you said you bought a couple FRM01 modules?  If so you can experiment with method 3 by programming your FRM01 module to be a Delay-OFF module.  In other words, when triggered it will turn its relay ON (and power the DCSRC) for exactly 1 second and then turn off.  Obviously for many sidings this gets expensive since the FRM01 relay module is 2-3 times the cost of a simple Delay-OFF relay.

stan2004 posted:

There are (at least) 4 alternatives to the annoying perpetual clicking.

1. Earplugs.

2. The original modified DCSRC, a.k.a. Perpetual Barking Watchdog.  No moving parts (no relay) so no clicking.

3. Use one Delay-OFF relay module for each loop or siding that's under relay control.  The Delay-OFF module will turn on (one click) the DCSRC for 1 second when power is first applied to the loop or siding.  The DCSRC generates the watchdog to silence the engine(s) on that newly powered section.  Then 1 second later the DCSRC turns off (a 2nd click) and stays off and silent no matter how long that section remains powered.  A diagram of this was shown in the post of 5/7.

4. Use one diode per loop or siding to only power the FRM01 when one (or more) loop or siding is actually powered.  So if no loop or siding is powered, the FRM01 is off and silent.   A diagram of this was shown in the post of 5/11.   But to be clear, you'll hear the clicking sound as long as one (or more) loops or sidings are active.

I think you said you bought a couple FRM01 modules?  If so you can experiment with method 3 by programming your FRM01 module to be a Delay-OFF module.  In other words, when triggered it will turn its relay ON (and power the DCSRC) for exactly 1 second and then turn off.  Obviously for many sidings this gets expensive since the FRM01 relay module is 2-3 times the cost of a simple Delay-OFF relay.

I went back and reviewed the information that you posted earlier. And, as luck would have it, the local mom and pop electronics store had the diodes! 

Good suggestions, although....I’m ruling out number 1.

I am probably going with the last scheme. And yes, I have an extra intermittent relay and an additional DCSRC module. At least I have it working and know what it takes.

Stan, thank you for your help and patience!