# New to DCC -- trying to determine what auto-reverser module to use



## EBrown (5 mo ago)

So I've been researching DCC, I plan to use DCC++EX for my setup. One thing I need to tackle is auto-reversing, specifically for 3 sections of my layout. None of them are a traditional "loop", they branch off one section of main line to another, but I don't think that _should_ matter.

This is one section of my yard, which is pretty much a great example of where my reverse loops are.

I've found the NCE AR-10, but I'm not sure if it's overkill or appropriate. It looks like I'll need 3 of them, which puts it around $175 for all the auto-reversing modules.

Is this a good module, or should I be looking at something different?


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## OilValleyRy (Oct 3, 2021)

That’s the one that I would use. 
As a cost saving thought exercise; do all 3 need to be automatic, or could 1 or 2 be manual? Manual reversers cost the price of a center-off toggle swtich. A buck maybe.


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## EBrown (5 mo ago)

I would prefer them all to be automatic. I don’t want to forget to switch one and then wonder why it keeps shorting lol


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## Severn (May 13, 2016)

I bought the all digital psx-ar1. Haven't even used it yet though. 

I bought it from Yankee dabbler but here's a different link






DCC Specialties PSX-AR Reverse Loop Diagram


Model Train News, Tips, Videos & Reviews | Tony's Trains




tonystrains.com


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## Lemonhawk (Sep 24, 2013)

There is also the Digitrax BXPA1 all electronic auto reverser, which also includes occupancy detection and circuit breaker
Check Yankee Dabbler's price.


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## EBrown (5 mo ago)

Lemonhawk said:


> There is also the Digitrax BXPA1 all electronic auto reverser, which also includes occupancy detection and circuit breaker
> Check Yankee Dabbler's price.


According to the instruction sheet LocoNet is required.


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## SF Gal (11 mo ago)

I am using a MRC AD 520 reverser control module and a Digitrax AR1 reverser module on my 2 reverse loops.









The AD520 is plug and play. The AR1 is also plug and play BUT...it has a Trip Current Adjustment potentiometer, MRC does not. The AR1 tuneable trip current is adjustable from .25 amps to 8 amps. Turning the TTC screw clockwise (orange pot next to green terminal block) increases the current trip point and turning the TTC screw counterclockwise decreases the current trip point. The total adjustment is approximately one half revolution of the TTC adjustment screw. The TTC adjustment is made using a full load on the reversing track--the total number of locomotives/cars that will be in the reversing loop. I never had to mess with the settings as my loop will not hold more than 2 engines under load...usually. Just food for thought.... I do not even realize the circuits are there after a while....works like a charm.


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## EBrown (5 mo ago)

I guess my next question is: so far, several reverse loop controllers seem to have built-in circuit breakers, can I wire my main-line up with a reverse loop controller to get the circuit-breaker part, or will two adjacent reverse loop controllers fight each other?


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## SF Gal (11 mo ago)

Your transformer usually has a built in circuit breaker and only supplies power to multiple reverse loop controllers. Then those Loop controllers control their own reverse loops as long as the main powers circuit breaker isn't tripped. They really would never conflict unless you have two different brands and one doesn't have a circuit breaker...than I suppost the main transformer would shut down upon a short.


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## EBrown (5 mo ago)

My main power bus doesn’t have a built-in circuit breaker, so I would need to use something external of some sort (which is why I’m wondering if I can just use a reverse loop controller to do the job). First plan was to use a cylinder / tube fuse but I’d like something that I can reset if needed.


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## SF Gal (11 mo ago)

How about a switched power strip...they usually have a circuit breaker ?


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## EBrown (5 mo ago)

I might get a dedicated circuit breaker just for safety sake. Looks like NCE makes one (NCE EB1) that seems to be a solid option, can put it between my controller and the main track.


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## DonR (Oct 18, 2012)

Why does your DCC controller lack a circuit breaker? All of the
major brand controllers have a circuit breaker standard.

You should never permit an 'isolated section' powered by
a reverse loop controller to abut a second 'isolated section'
so powered. A loco spanning the insulated joint would
cause a short circuit. The two controllers would each
begin reversing and eventually short.

If your track section shown in RED is an 'isolated
section' it appears to be far too short. A lighted
passenger train...or train with a lighted caboose
would trigger the reverse controller at both ends
again resulting in a short.

If you are uncertain where you might have a 
'reverse loop', draw your track plan using
RED for the 'right' rail, BLACK for the 'left rail.
Any time the RED 'touches' the BLACK
you have a 'reverse loop'.

Don


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## EBrown (5 mo ago)

DonR said:


> Why does your DCC controller lack a circuit breaker? All of the
> major brand controllers have a circuit breaker standard.
> 
> You should never permit an 'isolated section' powered by
> ...


As mentioned in the first post, I'm using DCC++EX, but I'm also using a hand-built controller, so I have to build-in the circuit-breaking feature.

With regard to the lighted-passenger-train issue: some information I read suggests that if you have a dead-zone at one end of your reverse loop that is the size of the lead and tail trucks on adjacent trains, and rewire the cars with a bridge-rectifier (which is relatively trivial) then the issue should be moot. My electronics experience says that should be the case, that as long as a truck can't bridge _both_ sides of the dead-zone at the same time, that a bridge rectifier on each truck in a powered passenger car would normalize the polarity and remove the issue.

Thoughts?


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## JeffHurl (Apr 22, 2021)

I have a Digitrax AR1, and if I had to do it all over again, I might try a different one. I got mine brand new about a year ago, and no matter how I adjust it, it sometimes takes longer than it should to trip.


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## JeffHurl (Apr 22, 2021)

JeffHurl said:


> I have a Digitrax AR1, and if I had to do it all over again, I might try a different one. I got mine brand new about a year ago, and no matter how I adjust it, it sometimes takes longer than it should to trip.


As a follow-up, I may buy a PSX-AR to see if it makes a difference. Based on the little research I have done, the PSX-AR is a better product that the AR-1


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## EBrown (5 mo ago)

If you do, please let me know what your luck is. I'll be ordering parts to start this build in 2-3 weeks.

I might order a Digitrax DCS52 Zephyr Express to start with, as I've read that it's often best to start with an out-of-the-box DCC controller to eliminate the potential of a bad DCC-EX setup. Looks like that particular controller also supports DC loco's, so I could start with those while I build track, and add decoders later.


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## JeffHurl (Apr 22, 2021)

If I do replace my AR-1 with the PSX-AR, it won't be until Winter when I start tinkering with the layout again. I have to learn JMRI in the meantime. I have 3 DS64s That I picked up in an auction I won a few months ago... and I may just try to computerize the control of my layout.


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## EBrown (5 mo ago)

Ah bummer, I'll probably already have to have at least one of my reverse-loops solved by then.


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## JeffHurl (Apr 22, 2021)

I have an old MRC AR module I got in that auction I was referring to. It's built around an old school relay, so it may have a slight delay, but I'll be happy to send it to you if you want to pay shipping. I have no need for it. At least you can play around with it to see if your wiring is working correctly. Then you can upgrade to a better module when time allows you to research them more.

Its' like this one
MRC Auto Reverse Loop Module


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## EBrown (5 mo ago)

JeffHurl said:


> I have an old MRC AR module I got in that auction I was referring to. It's built around an old school relay, so it may have a slight delay, but I'll be happy to send it to you if you want to pay shipping. I have no need for it. At least you can play around with it to see if your wiring is working correctly. Then you can upgrade to a better module when time allows you to research them more.
> 
> Its' like this one
> MRC Auto Reverse Loop Module


That sounds great, I'll shoot you a PM with the address if that's OK with you?


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## gazzab (Aug 20, 2019)

Tam Valley also have a great Auto unit.


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## Tranz4mr (Sep 3, 2013)

we use PSX-AR’s our Scenic Line Modellers Inc club layout. We have about 12 PSX-AR’s and have had no issues.


Scenic Line Modelers, Inc



DCC Specialties PSX-AR Power Shield Auto Reverser / Circuit Breaker


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