Skip to main content

I have posted this question previously, but still do not have a clear answer. I am wiring O scale 2rail with MTH equipment. Using Atlas switches, I need to wire the AUI unit to a Tortoise and control the switching using the DCS remote. Some have said this is not possible; others have said they have done it. Neither the MTH nor Tortoise tech people were helpful when I called, saying the other company was responsible for compatibility.

If someone knows how to wire this, I would really appreciate a clear diagram. Don't send me to a web diagram, since none of them cover this condition when using a remote. They assume the use of a DPDT switch instead.

Is anyone able to help. I would really appreciate it.

Original Post

Replies sorted oldest to newest



I have not chimed in on this forum in quite some time, but could not resist your call for help.  I build layouts and custom control panels in the Chicagoland area.  The MTH AIU has two different types of programmed output relays.  There are ten that have momentary contacts and ten that have maintained contacts.  They are generally used for operating switches and operating accessories on the layout.  For your purpose, you will be using the maintained contacts or the ones used for accessories.  If you refer to the wiring diagrams that come with a Circuitron Tortoise machine, you will only be looking at figure #2 or #3.  If you want to use DC power to control the Tortoise, you would use two power supplies.  If you use AC power to control the Tortoise, you would need only one power supply but use steering diodes.  The SPDT switches shown in these two diagrams would actually be your connections to the AIU ACC terminals.


I hope this makes sense to you.  If not, let me know and I will draw you diagram.



Norm, I'm guessing what you are trying to achieve is similar to what I have done using Lionel's accessory switch controller.  It has the same characteristics that Jim stated about the AUI.  I set it for constant voltage and use AC for power.  I have two diodes as Jim noted.  Lionel has a video on their webpage which shows how to set this up using the ASC, but I would assume it would be the same using the AUI.


Hope you get this to work, I really like this way of controlling the switches.


OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)

Link copied to your clipboard.