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Well, I finally hooked up my second Cab after getting my defective NCE smart booster replaced. I hooked up the standard NCE power cab using the 4 pin flex cable. I started my Shiny Blueline M1A on step 1 to get the sound going. Just sat and listened as it whined up and started hissing and making random sounds. Then I plugged in the 2nd basic 04 cab. All of a sudden the AC6000 that was about 5 feet behind the M1a took off at full throttle. I pulled out the cab wire and my heart stopped as I watched it slam into the M1a tender. I was going for the AC power but didn't make it in time. The M1 survived without any damage but the AC6000 suffered a broken coupler. I know there's a lesson here but have no clue what happened. I hadn't even touched the throttle for the 6000. Afterwards I started the system back up and had no problems with each cab assigned to a different engine.
Does this happen alot or was it a freak occurrence?
I've had this happen when switching between units with a Bachmann E-Z Command system too. It seems to a freak occuranace where the second engine (or cab, in your case) gets confused by the signals being fed to the first engine and it takes off down the track at full throttle. Apparently there's no fail safe position at "off", just full speed ahead. It only seems to happen when the second engine is standing still so I try to make sure the first engine is stopped, bring the second engine up, and then bring up the first engine. I've never had the same runaway when the first engine didn't have power applied. I did learn real fast where the emergency shutdown button was on my controller.
I have had this happen when the decoders were programmed for dual mode control. On NCE especially, you need to make sure that when you program the engines on the programming track, that you make sure that they run in DCC mode only.
Apparently, every once in awhile, a stationary engines that is programmed for dual mode will just take off without you sending any commands to it. just put the engine back on the programming track and when asked if you want DC mode, select NO. you shouldn't have any more problems.
Bob, that's probably exactly what happens. The E-Z command system is dual mode and most of my decoders are dual mode. Since the controller will put out DC and DCC, an engine with a dual mode decoder will sometimes respond to the "DC" voltage in the track and roar off on its own. Unfortunately, E-Z Command doesn't have the option to access CV's so I can't change that behavior. Another reason I've been shopping for an upgrade.
If you have access to CVs, CV29 set to 2 will turn off DC mode. I do this to all my engines. When the track goes DC, it will stop the engine instead of letting it go off at full throttle.
I also set CV11 (packet timeout) to 10 or so - it is the period of time the engine waits before stopping.
