Installing DCS in 2 Rail Sunset F Unit Pair Need Help!

What do you mean by the reverse relay is failing? There shouldn't much difference in the wiring than any other upgrade.

You should also put thus in the DCS forum.

Ralph

Charly, if you want this thread moved to DCS forum, click on the triangle at the bottom of my post.  This will report my reply to the moderators, and in the drop down box, simply ask the moderator to move your thread.

I posted here because of concern re: these being 2 rail engines and not knowing much about them.  Also, prior post regarding this didn't net much help from the DCS forum.

 

But thanks for the responses all the same

 

Suggestion only:  mention that you tried a previous forum with little or no effective help in the original post in the new forum.  Meanwhile, hope you get the help you need, Cheryl.

 

DCS is a proprietary system.    The mfg should have documentation if they will share it.   DCC manufacturers share theirs.

 

A 2 rail engine is wired the same as a rail engine with one difference.    On 2 rail, one set of pickups is off one side, and the other set is off the wheels on the other side.   The two sides must be kept separate.    On 3 rail, the pickups from one side go to both sets of wheels, and the center roller is the other pickup.

 

DCS uses some sort of relay - - that implies mechanical.    Very strange?

On a reg 3 rail up grade there are only 2 wires for power pick up . red center rail and black outside .

 

With 2 rail there still would be the same 2 wires. One to each set of wheels on each side of the  engine.      Each set of wheels must be insulated from  each other.

 

 Is there any chance the direction of the engine sitting on the track would make a difference. Maybe turn the engine  around or reverse track feeders.

Any decoder should work and not care if it's in two rail or three rail if it's wired correctly. A relay is just something to help with high current. It is not strange at all. They can fail. I have not had one fail myself.

 Some three rail installers struggle with two rail if they've never done it. It is simple but as posted, the wheels must be isolated electrically and that includes from the frame and any other grounding, unless desired.

 I have seen where simple un-intentional or un-wanted grounding happens even through the couplers. You must think it thru!

 It doesn't matter if it's DCS or DCC!! They work the same. 

I once installed DCS in a 2 rail engine and had no problems other than the well known issue of PS 2.0 being polarity sensitive. Not to say that I know it all but I've never heard of the reverse relay. 

 

Are you trying to run both (two) Sunset F units off of one DCS board? I'm not sure if the board can handle that. I believe MTH uses a slave board in the second powered unit in their own F unit sets. 

MTH does indeed use a slave board in their second powered unit. This might be a different situation, though, if the Sunset A-B is using single-motor drives and the flywheels are compatible. The current draw may be within tolerances for the Proto-2 board, but the units would need to be tethered together. As stated above, you'd have to put in a polarity switch (DPDT) and by default have the hot picking up from the engineer's side.