TMCC went wacky

[Anonymous]

I was playing with the train with my 5 year old when the TMCC went dead. It sometimes does this (I posted the problem before) but it's easy enough to get it going or reset the system. Anyway, the engine is not accepting the commands so I ask my 5 year old to move it an inch or two forward to get a better signal from another piece of track. When my son touches the engine it leaps forward at full blast speed. I have the TMCC set to a moderate top speed so my sons can't wreck the train. However the engine is now going FULL speed and still won't accept commands from the CAB. I couldn't slow it down or stop it. I lunged for the transformer but was too far away to get there in time. The loco went flying off the track and crashed. I don't know what made the engine jump to full speed while still ignoring the CAB signals and speed limits. My son just touched the engine. The buttons on the engine (for conventional mode) were not hit. I think the problems I'm having with the TMCC may be more serious than I thought.

[Anonymous]

Hey,

How is your layut setup and what loco are you using?

[Anonymous]

It's just Fastrack on the floor. The Loco is SP overnight freight steam #31963. It's a nice engine actually.

[Anonymous]

Make sure your Command base is not on the floor directly, but rather on something.

[ChiefEagles]

Chris, why not on the floor? Mine has been on carpet all along. TIU too. Do you suppose he "threw" a magnet?

[wrmcclellan]

1regal,

You either have a connection problem (Command Base to track & transformer common) or a ground problem where the Command Base power supply is plugged in. You must have a good earth ground for TMCC to work reliably. The Command Base power supply has a 3 prong plug and it must be plugged into a grounded outlet.

There is also a chance that you have a ground problem in the loco (very low probability) or a loose antenna connection (higher probability).

Regards,
Roy

[Anonymous]

Some floors could be fine, Others may give problems.

The rebar in the floors can tweek the signals, the same with walls, ceiling.

Im not sure if it has Oddyessy or not

[Jim Duda]

Is your Command Base power supply plugged directly into a polarized (grounded) wall outlet or into a Power Strip with a built in circuit breaker? I'm with Roy on a potential GROUND problem...

[Anonymous]

The command base and transformer are plugged into the same wall outlet which I tested and is fine. I went through a lot a wire and plug diagnosis when I posted my first problem a while ago - which was the TMCC going dead, just not accepting the signals. I think this problem is in the Fastrack. The train actually changes speeds by itself sometimes. I am planning on making a permanent layout in the basement. This Fastrack floor setup is just to keep the kids busy. The signal problems are a nuisance, but since it's not a fixed layout, I'm not going to kill myself trying to fix all of them. I was just freaked out and puzzled that the engine could somehow get a full charge of transformer volts, even with the command base plugged in, and go on an runaway rampage until it derailed. By the way, I have not touched or changed anything and it's been working fine for several days. [?]

[wrmcclellan]

1regal,

The engine going crazy is a sign that the engine "lost" the TMCC signal - so it thinks it is a conventional engine and the track voltage is at 18 volts, so it launches like a rocket.

I agree that you should not beat this up for a temp layout. Since your loco changes speed on the temp loop, there may be some common rail continuity problems with the Fastrak. The common rail is how the 455 kHz TMCC carrier signal (which is on even if no commands are sent - this acts a a TMCC "keep alive" signal for the TMCC locos) is transmitted to the locos. If this 455 kHz signal is lost - the loco reverts to Conventional operation.

As you may be aware, the TMCC Cab1 uses 27 MHz to communicate to the Command Base. The Cab 1 radio link does not communicate directly to the loco.

Regards,
Roy

[Anonymous]

It has happened to me a few times. I run a power house transformer 18 volts 180 watts, and aTMCC command base. I have all atlas nickle track. I had several engines on one powered loop. All of a sudden two of the engines took off. My layout is off the floor 3ft and it is on top of plywood. I think the engines lost the signal and reverted to conventional control. It must be interference or something similar. Once one of my engines hit a dead space on my layout or so I thought. It had no lights and nosounds. I came alive and took off.