This problem has haunted me on two different layouts using two different manufacturer's tracks. Most of the time, I have 8 or 9 of my engines somewhere on the layout where they will sense power from my Z-4000 transformer when it's power is applied to the track. After I have turned the 110 v. power on to the transformer, I increase the voltage to 18 volts output. When I do this, some of the engines will power up on their own. They go through the standard startup sequence, but the volume is at maximum, and the smoke volume is on high, regardless of the DCS settings. The only command they respond to from the DCS remote is the Shut Down button. They don't move, they just start up, and I have to scroll through the lists and select them and push the Shut Down button for each one. Sometimes, so many come on that I just kill the 18 volts and let them all reset on their own. Then, when I reapply power, they're usually quiet and respond to the remote as they are designed to do. My AC4400 used to do it all the time, but it stays quiet now. Instead, the F7's are notorious for starting on their own. Occasionally, it's the 4-8-2 RF&P or the Kanawha, even the switcher diesel chimes in every now and then. It makes no difference where they are on the layout or how many are on there. I even tried removing them from the DCS and adding them back in. All are MTH engines, some older, some new, with new GarGraves track and Ross switches. I have no trouble with DCS operation as long as the remote originally turns the engine on. At first, I thought I needed to have the remote powered up before I applied track power, but that doesn't seem to matter. I've slowly ramped up the transformer output, but that doesn't make any difference, either. Sometimes I hear an audible click from a few of the engines, some of which will then start on their own. I am running the power through Fixed 1 of the TIU, my sole source of track power for awhile, but then I insulated the sidings and used Fixed 2 to power them and placed an on-off switch on the TIU input side. I can park my passenger cars there and not have them drain power from the transformer to light up the interior bulbs (2 - 4 amps worth!). Power is evenly distributed throughout the trackwork. The Ross switches are powered by the 14 v. fixed accessory output of the Z-4000.

This is a minor inconvenience, because otherwise the 10 x 16 ft. layout runs flawlessly. Any suggestions about what's causing this?

All comments appreciated. Thanks everyone. This is a great forum. Good information, and comical at times. Sure beats the newspaper.

Mike
OGRR Run 220
"O Gauge In Small Spaces"

quote:

I've slowly ramped up the transformer output, but that doesn't make any difference, either.

Mike,
Some of your engines are missing the "watch dog" signal when the power is applied to each TIU channel. When this happens the engines default to conventional mode and start up. Using either Start Up or Shut Down directs them into command mode. Instead of raising the power slowly you need to raise it faster.

They are starting up when you apply power because they receive power but not the watchdog signal. The ones that you are hearing the audible click and not starting up on their own is how it should be. First off I'd pick up a cheap z-500 brick and power the TIu with that into the AUX IN. That would eliminate the problem being from you ramping up the power too slowly. You can also try a cheap Radio Shack wall wart to power the AUX IN. Unless you are applying power to the track before the TIU receives power the engines should not start up on conventional mode.

quote:

Originally posted by Gary:

quote:

I've slowly ramped up the transformer output, but that doesn't make any difference, either.

Mike,
...
Instead of raising the power slowly you need to raise it faster.

Also, you don't need to scroll and find each engine to shut them down when this happens. You can use the All Engines mode. ENG button / softkey All / Shut Down.

Rand

There's a limit to the number of PS2 engines that can receive the watchdog signal successfully at the same time on the same TIU channel. This may vary from layout to layout. On my layout, with all channels powered by Z4000's, it's about 7/channel. That's one reason why every one of m PS2 engines resides on a toggle-switched siding.

Also, as was previously noted, you need to increase track voltage quickly to the voltage necessary for a PS2 engine to "see" the watchdog signal. I've found that the voltage required is approx. 10 volts, however, this may increase if many engines are drawing power simultaneously.

In earlier release than 4.x, the watchdog is only present for a second or so. In 4.x it's present for about 5 seconds.

Barry thanks for the heads up, I have 7 engines on 2 loops each with each loop on a TIU channel without any watchdog issues. When the UBoat Rdg comes in (some day), I will be checking to see if I have any problems when I get 8 engines on my 2nd level inside loop. (4 trains)

Mike,

Sounds like the engines are starting up in Conventional, versus Command, mode.

As Gary explained, this will happen when the watchdog signal exchange from the engine(s) to the TIU does not occur which causes the engine(s) control circuits to enter Conventional mode.

Not sure what your setup consists of? But my setup, with seven PS2 engines and DCS control at version 4.02a, always goes into Command mode when I power-up.

Here's my setup & power-up sequence:

SETUP
With all devices powered off:
-TIU AUX POWER INPUT jack connected, via Radio Shack 273-1716, AdaptaPlug type M, to a Radio Shack 273-1690 Supply with Supply output setting at 18VAC.
-Track Transformer ON & power output setting at maximum (16-18 VAC).
-Plug Radio Shack Supply and Track Transformer into a power strip.
-With power strip turned off, plug power strip into AC Line power.

SEQUENCE
With all devices setup:
-Turn on power strip to supply AC line power to TIU & Transformer at the same time.
Note: To make this a one step power-up I use an "xmas tree" extension cord with a foot switch to do this.

This setup and sequence ensures watchdog signals are sensed so that all the engines come up in Command mode. That is, the engines are powered up quickly when the Track Transformer is turned ON. Then, after a few seconds delay, the TIU comes on line after it's cycle-up is complete and the TIU will sense the watchdog signal(s) already present.

Tom

Thanks guys, for your responses.

Not much time to do all the variables, but I tried ramping up the track power quickly, as you suggested, and every engine obeyed. I did that three times, and they remained quiet.

Then, I brought it up slowly, and sure enough, two of the engines started, one being the AC 4400. I powered back down again, and returned to another quick ramp-up test, and the AC 4400 came to life. I killed the power, ramped up quickly another two times, and each time the 4400 started on it's own again. Will maybe try to reload it,and it might settle down.

I do have the TIU on it's own power, by the way. In fact, it's a brick from a smaller MTH transformer. I have a power strip that everything is plugged into, and I actuate it all at the same time. The transformer toggle switch remains on, and I let the master switch turn everything on together.

Rand, thanks for the tip about the softkey "All". Never realized it existed. After having DCS for a couple of years, I just figured out that the soft key assignments can be moved around. I now have them set up to be more or less universal in their order, and even printed a little reference booklet that shows what's available from each engine.

I need to do a little more testing, but I think the problem may go away as long as I "ramp rapidly". Even though tonight's quick test produced a failure, I don't usually turn the layout on and off repeatedly in a short period of time. If the 4400 behaves the first time I power up, that will satisfy me.

Thanks again, everyone. But wait, there's more ...

Coming soon: a TMCC control module wired into the TIU with the 9 pin D connector cable, so I can run an Atlas diesel using the DCS remote. Problems there, too. But that's for another time.

Mike