MTH 30-1646-1 PS3.0 Tri-Plex will not move

First when you say it won't move, what mode are you testing in? Conventional or DCS?

While it's not supposed to happen, I have witnessed and have been able to prove some but not all engines will disable convetional operation mode just by adding to a DCS system. So say previously this engine was run on a DCS layout and was added to DCS- that can leave the engine in a state where conventional mode is locked out. It may require you to use a DCS system to reset the engine to factory defaults to get it to then run in conventional.

I am trying to run the Tri-Plex engine in conventional mode with a transformer. My mistake, I should have noted that in my original post.

idea-thinker

@idea-thinker posted:

I am trying to run the Tri-Plex engine in conventional mode with a transformer. My mistake, I should have noted that in my original post.

idea-thinker

You can try using the conventional reset- but that may or may not work to reset this condition. You might need DCS.

From the PDF manual for the engine.

Rest defaults: 1 Horn/Whistle, 5 Bells (from Neutral only)

https://d2frr7198pxftr.cloudfr...dO3.3Z1uGzg4cd9nVYR9.

Video https://www.youtube.com/watch?v=RGt6LvTHQJ4

So as a learning opportunity and good troubleshooting practice is understanding how PS3 steam engines and the control systems work.

Specifically, in PS3 Steam, it is a 2 board system. There is a board in the tender called the tender board, and a board in the engine called the boiler board. They are connected using a 6 wire system (may include a circuit board wireless drawbar) that carries communications back and forth as well as track voltage between the 2 boards.

The tender board is the larger board and has the super capacitors: It's job is to control the entire engine "system", make the sounds, control the light outputs of the tender, control the coupler on the tender, accept the input of the manual volume pot and the smoke volume pot, last it decodes the DCS or DCC signal from track power. Again, effectively, this is a huge chunk of most of the engine function- especially sounds, but also is what decodes the DCS signal or conventional in conventional control.

The boiler board controls the lights (headlights, class lamps, cab light, number boards, smoke unit, and the main drive motor. It's a smaller board that is commanded by serial data over the 6 wires FROM the tender board, but also sends info like motor loading and chuff sound trigger back to the tender board. Key note- the boiler board in the engine will not di anything if not connected to a working tender board. All of it's outputs default to off state on boot and looking for the first command from the tender board.

Knowing the above rules can be critical in troubleshooting PS3 steam.

@idea-thinker posted:

I have a MTH 30-1646-1 PS3.0 that does not move but the lights come on, the Horn and bell work. Crew talk works as well. It does not make an attempt to move at all.

So from your statement, we have a few things that work and one major one (motion that doesn't).

#1 Sounds- being the tender board makes the sound and directly powers the speaker, this implies the tender board is at least alive and hopefully working.

#2 Lights- specifically engine lights (headlight, cab light, class lamps, number board, firebox glow)- you are indicating these seem to be working. Knowing that the tender board communications is required to turn on the LED lights, this implies that the communications is probably working between tender board and boiler board. We know the boiler board turned on the lights but we just get no motion. This also means the both boards are seeing power- as each board uses track power for the functions.

So an example, say we had a situation where we had NO lights on the engine, none at all, no smoke unit operation, no movement, engine just flat out appears completely dead- but we get sounds out of the tender- then we suspect the drawbar electrical connection. This is again because on power up, the boiler board defaults off on all outputs unless it gets a command to turn something on, and if that command never comes= engine side appears dead.

Luckily again, you don't have the more problematic situation, if the lights are working on the engine, and say smoke unit and fan are on, but just no motion, that isolates the problem more related to main drive motor control.

Other things you didn't say. you didn't say the motor hummed when you tried to command speed or movement- a sign the motor is trying but may be physically jammed. So, based on what you said, my assumption is the motor drive section of the boiler board is not getting motor drive commands.

I stress again, this is where an experience point kicks in- knowing that while it's rare, you are specifically trying to run a PS3 Steam engine in Conventional only using a transformer. Because of that scenario- and the fact the lights work, sounds work, in theory the engine last ran with no complaints, you've gone and checked the drawbar, and we know the drawbar had to work for the LEDs in the engine to even light up so that reduces the chance this is a drawbar connection based issue.

It's entirely possible the boiler board can get damaged and motor driver section can be damaged but the LEDs still work, but we are brimming with optimism that this is just a rare but possible programmed state condition where conventional is disabled- thus reset the engine to factory defaults in theory resets back to enabled for conventional control and all works fine.

@Vernon Barry posted:

So as a learning opportunity and good troubleshooting practice is understanding how PS3 steam engines and the control systems work.

Specifically, in PS3 Steam, it is a 2 board system. There is a board in the tender called the tender board, and a board in the engine called the boiler board. They are connected using a 6 wire system (may include a circuit board wireless drawbar) that carries communications back and forth as well as track voltage between the 2 boards.

The tender board is the larger board and has the super capacitors: It's job is to control the entire engine "system", make the sounds, control the light outputs of the tender, control the coupler on the tender, accept the input of the manual volume pot and the smoke volume pot, last it decodes the DCS or DCC signal from track power. Again, effectively, this is a huge chunk of most of the engine function- especially sounds, but also is what decodes the DCS signal or conventional in conventional control.

The boiler board controls the lights (headlights, class lamps, cab light, number boards, smoke unit, and the main drive motor. It's a smaller board that is commanded by serial data over the 6 wires FROM the tender board, but also sends info like motor loading and chuff sound trigger back to the tender board. Key note- the boiler board in the engine will not di anything if not connected to a working tender board. All of it's outputs default to off state on boot and looking for the first command from the tender board.

Knowing the above rules can be critical in troubleshooting PS3 steam.

So from your statement, we have a few things that work and one major one (motion that doesn't).

#1 Sounds- being the tender board makes the sound and directly powers the speaker, this implies the tender board is at least alive and hopefully working.

#2 Lights- specifically engine lights (headlight, cab light, class lamps, number board, firebox glow)- you are indicating these seem to be working. Knowing that the tender board communications is required to turn on the LED lights, this implies that the communications is probably working between tender board and boiler board. We know the boiler board turned on the lights but we just get no motion. This also means the both boards are seeing power- as each board uses track power for the functions.

So an example, say we had a situation where we had NO lights on the engine, none at all, no smoke unit operation, no movement, engine just flat out appears completely dead- but we get sounds out of the tender- then we suspect the drawbar electrical connection. This is again because on power up, the boiler board defaults off on all outputs unless it gets a command to turn something on, and if that command never comes= engine side appears dead.

Luckily again, you don't have the more problematic situation, if the lights are working on the engine, and say smoke unit and fan are on, but just no motion, that isolates the problem more related to main drive motor control.

Other things you didn't say. you didn't say the motor hummed when you tried to command speed or movement- a sign the motor is trying but may be physically jammed. So, based on what you said, my assumption is the motor drive section of the boiler board is not getting motor drive commands.

I stress again, this is where an experience point kicks in- knowing that while it's rare, you are specifically trying to run a PS3 Steam engine in Conventional only using a transformer. Because of that scenario- and the fact the lights work, sounds work, in theory the engine last ran with no complaints, you've gone and checked the drawbar, and we know the drawbar had to work for the LEDs in the engine to even light up so that reduces the chance this is a drawbar connection based issue.

It's entirely possible the boiler board can get damaged and motor driver section can be damaged but the LEDs still work, but we are brimming with optimism that this is just a rare but possible programmed state condition where conventional is disabled- thus reset the engine to factory defaults in theory resets back to enabled for conventional control and all works fine.

Vernon;

Thanks for the run down on the operation of the MTH ps3.0. It sounds like it might only need to be factory reset.  I will have to find someone with a MTH control system to give it a try.

idea-thinker

what transformer is being used?

does he know how to shift it out of neutral correctly?

I hope it's not this one

https://www.lionel.com/product...transformer-6-14198/

@Vernon Barry I am a bit out of breath reading your description, lol, BUT thank you for it. I am also having issues with my MTH ps3 Blue Comet. I am putting off taking it into a shop for repair (mainly because I moved away from my local shop where I purchased it) but also because I feel like I just need to figure it out myself. I am not with my layout at the present but as soon as I am I will take another look at exactly what it is doing while keeping your advice in mind.

Mikki

If you have a transformer with bell and whistle, you can do the conventional reset or unlock procedure without a DCS system.  Following the directions on Bell/Whistle combo in any PS-2 or PS-3 instructions.  They are the same combo.  G