Hello! The D300 diode on my TIU has gone bad, I was wondering what the exact replacement part would be? Thanks!
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I use this one: 1500W 33.3V TVS at Digikey
@art_legend posted:Hello! The D300 diode on my TIU has gone bad, I was wondering what the exact replacement part would be? Thanks!
Look at the diode itself and somewhere in the marking you'll see either 33, 36, or 39. There is some discussion about the choice in this post . DigiKey carries all of them though you'll end up paying more for shipping than the parts themselves. There is a US seller on eBay that has the 33 for somewhat less than what you'd pay at DigiKey...even uses "Lionel" in the listing title!
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Is this the most common TIU failure point? Is this the one that fails reducing that channel's output to zero?
Don Merz
A shorted TVS usually blows the fuse.
There can be a few TIU failure points depending on function or channel. In this case the TVS usually shorts as John stated. I would say it does not blow fuse though. I have never personally found a blown fuse on TVS short. The transformer or power source would trip first. Fuses are 20amp, and most transformers trip at 10 or less. If you have no power out. That would be fuse or bad terminal connection for Fixed. Can add Power Fets if a variable channel. G
Another question: Since this issue has arisen, I have been having trouble getting the TIU to detect my AIU. I can boot the TIU just fine using a wall wart, however it doesn't detect the AIU. Could these issues be connected (i.e. could the wall wart not be supplying enough power to control the AIU), or is this more likely an issue with my AIU cable?
If you're having a problem with the TIU, you need to resolve that first, then you'll see if you still have an AIU issue.
The AIU does draw power from the TIU, so if you have a marginal power supply for the TIU, that may not be enough for the AIU as well.
Got the diodes in this week, as for the AIU just realised I was using the wrong cable type. I had thought it took a standard phone cable, but it apparently takes a special 6P6C reverse cable.
Correct, we've talked about that here a few times.
Mmmm I wonder. I just discovered a bad output on my TIU. It was strange because it would cause Lionel tenders with electronic whistles to randomly blow. I also have a weird problem with a proto 3 steam turbine stopping and surging forward after about 5 minute of running, it was also causing my TMCC engine lights to flicker... It was acting like I was getting random DC voltage spikes. I switched the output on that track to variable 2 and the problems went away.
could the diode be causing this ?
