Powering AIU & TIU with one power supply?

You power your AIU separately?  Mine get their power from the included cable that attaches to the TIU.

It's been a long time since I wired  my AIU to my TIU. I can't remember why I added a separate power source. So you're saying I can unplug the separate power supply from the AIU and it will work? I've been running trains on and off for 10 years with the separate power supply. I guess I could have saved a lot of electricity.

I am pretty sure there is no separate power supply for the AIU, at least mine does not even have a spot to plug one in.

https://mthtrains.com/sites/de...ction/20as16818i.pdf

Sorry, I should have looked closer. The Z500 is powering the IN on the inputs for the accessories I have wired up on the AIU. It's been a bad Monday! That being said, is there a reason why I couldn't use one power source to power the TIU and the inputs on the AIU?

When you say the Z750 is powering the TIU, is it plugged in to the TIU's AUX round-plug or is it going into the FIXED 1 RED/BLACK jacks thereby also powering the FIXED 1 Track?

It's plugged into the AUX input. It is not used for track power.

You could power both by connecting power to TIU Fixed Input 1 but you would be better served powering the TIU with a wall wart particularly if you run conventional mode.  You can use any wall wart between 12 and 22 volts, ac or dc that can support 1.5 amps (it's pretty flexible).  You probably have a drawer full of these thing from other electronic devices,  Just find one with the correct plug.

Thanks for the info!

I'll stir up the pot a bit and say you should buy a 12V DC 2 Amp (24 Watts) wall-wart for ~$2 (free shipping from Asia) on eBay which has the right connector to plug into the TIU AUX.

This frees up your Z750 (75 Watt) brick which can be put to better use elsewhere.  You do NOT need anywhere close to 75 Watts to power your TIU.  For example you can replace the Z500 (50 Watts) with the Z750 to provide more power to your accessories.

Strictly speaking, you could use a single Z750 to power the TIU (via the AUX connector) and your accessories.  But there are some squirrel-ly caveats that have to do with how the TIU connects the AUX power "hot" to the track common.  So while you could probably get it to work, it would be what I'd call unconventional wiring depending on what kind of switches or accessories you are controlling with the AIU.  Given your comment about last having looked at your wiring 10 years ago I don't think  you want to mess with this kind of fine-print.

Just my opinion of course.

Stan, I'll try the adapter.  I'll keep the Z500 to power the accessories. I think your last paragraph is very informative. I've never had problems so why take a chance.

Show a picture of your AIU setup. I want to see this.

II wired this up a long time ago before I knew about this forum. It would have been done much differently with input from the forum. 

The AIU does not need a separate power supply to run the electronics inside it. Power for the AIU electronics comes from the TIU, period. Your connection(s) to the IN on the inputs for the accessories is the power that drives the accessories. 2 completely different things. As others have stated, I would  (and do) use a wall wort to power the TIU. That keeps the power feeds for the accessories separate from the electronics. Be sure you have enough ampacity to power all the accessories that you intend to operate at once (not necessarily ALL the accessories!) Some only operate sporadically, while others (the ones to worry about) run continuously.

Chris

LVHR

Yes, In one of my response posts above I clarified that I realized the power supply was for the IN on the inputs not the AIU as I originally stated. I've already ordered the wall wart that Stan mentioned. That will free up my Z750 to power my accessories. I don't have that many accessories tied to the DCS system so I'm sure the Z750 will be enough. Stan's post definitely made up my mind that I needed 2 separate power sources. 

As I said before - I wish I'd known about this forum when I originally started wiring my layout. I live in the St. Louis area and it seems like I'm the only one with DCS.

Thanks, 

Don

Chris said it all.  Why do what you are doing it is not needed.  How about hooking up things the way they were designed to operate?  You need to buy the book Barry has available.  

The right way is always the best way.

Marty my number is 314-608-3075. Would you call me?

Different Marty here. I live in the St. James area and go to St. Louis quite regularly, I may be of some help with the DCS system.

Marty W, I think I've got things under control. If you're ever near O' Fallon Mo you can use the phone number above and call me if you'd like to see my layout. Also, we have friends who live near Belle that we visit 2-3 times a year. Would you mind me and my wife stopping by? Thanks, Don Keence

 At the moment, and probably the better part of this year, I have nothing to stop by and see! LOL! I have three teenagers living in my house. Not much train time over the past few years! 

I do have a nephew in Troy though. I' d love to see your layout sometime!

Hopefully you get train time soon. You're welcome to stop by any time.

I have plenty of train stuff for a layout bigger than my house, look for me on the for sale board soon! I'll call you when I get a chance. I'm starting to get the trains out of hibernation at this point, the pressing issue is/was........basement or an additional building? Keeping in mind I'll have girls in college for the next 8 years or so I'll assume I'll be pretty broke. Until then I need the most action for a layout in a limited space. That's been my issue! The other issue is I spend way too much time thinking about my issue! You get the idea! LOL!

I like your thought process.