Operating Track Issue

BC,

The milk car uses the control rails on the operating track section to activate its mechanism. The way that it does this is more than likely different from how the other operating cars are activated:

• Do the other operating cars that do work, also use the control rails, or do they use the magnet instead?
• If the other cars use the control rails, do they use one control rail or two?

Obviously, there's a difference between what activates the milk car vs. what activates the other operating cars.

Also, while I cannot speak to the FasTrack control box for its operating track, the old postwar controllers were set up so that one or both buttons activated more than one set of contacts when pressed, i.e., the button would complete two circuits at once. The AIU ports, however, only activate one circuit for each ACC port.

You need to understand what are the requirements for activating the milk car and then wire your AIU port (or ports) so that they emulate the actions of the manual controller.

The Lionel operating track sections all have two operating rail sections. One section is connected to the center electro magnet the other is connected to its own wire. Operation in the uncouple mode is to connect both rails and the magnet to power. This will operate most newer operating cars. This is the UNCOUPLE mode. Older cars requier the UNLOAD mode. In the unload mode the rail connected to the electro magnet gets connected to operating power and the other rail gets connected to the outside rail. The car gets its power between the pickup rails and not from the pickup rail and the outside rail. This is the case with your milk car.

There are two work arounds for this problem. In the first simply connect the isolated operating rail set to the outside rail and only turn power on to the set connected to the magnet. The problem with this is that only one rail set will operate your cars, but also some engines with wide pickup rollers or out of position rollers will short out to the grounded control rail.

A better solution requires the use of an additional AIU port and two relays. One with DPDT contacts and one with SPST contacts. Connect one AIU port to operate the DPDT relay and label it UNLOAD. Now use one set of contacts to connect power to the set connected to the magnet and the other contact to connect ground to the isolated set. Connect the other AIU port to operate the SPST relay and label this UNCOUPLE. Now connect the set connected to the magnet to the port with the SPST relay and the isolated set to the relay contacts. Connect the other relay contact to power. This will apply power to the set connected to the magnet and pick the relay. The relay will apply power to the isolated set. This method keeps the isoleted set insulated during normal running eliminating the shorting problem. The SPST relay is necessary to keep the connections from shorting out the isolated section when the unload button is pushed.

In the first case the original AIU connection remains and can be labeled UNCOUPLE.

Barry / HOSO&NZ,

Thanks so much for your reply.  Do either of you have a wiring diagram for the work around HOSO&NZ suggests?

Barry is this work around included in your DCS Companion guide?  I have the 1st edition.

Thanks again for the help I've been using DCS for a year, but there is so much to learn.

BC

BC,

is this work around included in your DCS Companion guide?  I have the 1st edition.

No, it's not in either edition of the book.

The interesting thing is that I've implemented several Gargraves operating tracks using DPDT relays in conjunction with the AIU, in just the manner that HOSO&NZ describes in his post. I keep both control rails disconnected and then use the AIU to activate an external relay, which puts Hot into one control rail and Common into the other.

Unfortunately, I don't have a diagram for the circuit.