You can obviously use any 12VAC power source, but it should be TOTALLY isolated from anything else on the layout.  You can, of course, splice the supply cord for the base to any compatible 12VAC output as long as it's isolated.

I have to wonder where you got a 12V 450 amp transformer, how big is that sucker???

In order connect the earth ground lead, you need to run a wire from the outside barrel of the power jack or pin 5 of the serial data connector.  Either of those places will work, they are electrically connected internally.  The earth ground lead has to go to the 3rd prong of a properly grounded outlet, or something like the water pipe ground.

Thanks GRJ...I appreciate the helpful insight.  Can I ask a couple of follow-ups so I don't fry this thing on the first go.

I don't have the AC barrel jack from the Lionel TMCC base....I was looking to use a DC barrel Jack that fits the Lionel TMCC base but I am not sure if this is possible.  I know that you have to be careful with polarity on the DC jacks and I don't know if there is a different AC jack....if there is I couldn't find it.  Do I have to be careful with polarity if I am connecting AC power (from the power pack wires) to the DC barrel jack (with its two wires).

On the original equipment with the three pronged wall power source, I am assuming that the two wires carry 12v AC hot and AC ground from the transformer to barrel plug.  Is this right and is it correct to connect the AC ground on the outside barrel of the jack so that this can also carry the earth ground.

Thanks for your patience.  You have forgotten more about this stuff than I know.  

Thanks.     Greg

Power unit is dedicated to the TMCC base and is 450 mamps.....I had read that 100 mamps is what is required to power the unit so this should be fine.

gunrunnerjohn posted:

I have to wonder where you got a 12V 450 amp transformer, how big is that sucker???

That would have to be 350-400 lbs.!

You don't need the original plug, the TMCC BASE takes a 2.5/5.5mm plug, you can get them from a number of sources.  Note that the more common 2.1mm/5.5mm plug won't fit as the center pin in the base is too big.  If you're using the transformer for only the base, no polarity issues involved, just don't connect that transformer to anything else.

Greg ----12 volt 450 amps is compartively huge current capacity. Please tell us more about this transformer, source, brand,etc? Photo maybe?

Wow 12V 450 amp. I’d luv that puppy for running my inverter or given enough inverter capacity every layout at our annual Lionel Collectors Club UK train show!

Seriously though to put that amperage in perspective. I use a 75amp 12V supply and that happily runs a 1000W 120v 60Hz pure sine inverter. Which easily runs our 16’x8’ layout with 4 loops and accessories.

Nick

Thanks to all especially GRJ.

450 milli amps not 450 amps.....very sorry for the confusion.

This is a great forum and very helpful to guys like me who are new at this hobby.

Best.....Greg

Thanks for the update Greg. That explains things 

Nick

By chance did you try Trains@SandWparts.com as he still had a few the last time I talked to him. 

Thanks Greg.

I contacted S&W today about this, they are out of stock on the original transformer.

Rob, are you confident that the higher amperage won't damage the base unit?  I don't know the answer to that; it's a question I just asked Lionel customer service because they currently sell a $20 transformer for the switch controllers SC1/2 that is also a 12v class 2 transformer with a barrel plug that puts out 300mA (vs. 100mA for the original TMCC wall pack).  I'll post their response if/when I get one.

Excessive current capacity will NOT damage the base, the electronics only draws the necessary power.  Think about it, if you plug a 5W light into your 15A receptacle that is capable of delivering around 1800 watts, it simply uses 5 watts.  The same principal applies here.

That's encouraging.  There is much discussion about the requirement for an electrical ground - does that mean 3 prong only or are polarized plugs suitable?

NNJ Railfan posted:

That's encouraging.  There is much discussion about the requirement for an electrical ground - does that mean 3 prong only or are polarized plugs suitable?

This is the only "special" feature of the Lionel power supplies - the barrel has to be linked/connected/coupled to the third, (round, grounding) prong of the power supply(it is done within the wall wart enclosure) for the TMCC/Legacy signal to propagate.

There is a work-around for regular off-the-shelf wall warts with the same electrical specifications but lacking the ground pin, and therefore the coupling to the AC/house earth ground, if you come up otherwise empty-handed.

Rob....I am the original poster here and believe I am almost set but I have one more question.  Instead of connecting the AC ground (third prong) to the serial connector( 5th port) as you had suggested in earlier posts, I would like to connect it to the barrel jack like the original transformer had.  The issue for me is that the barrel jack already has the two output wires from the wall wart connected.....one to the inside barrel and one to the outside barrel  If I connect this third wire(AC ground) to the outside barrel where there is already AC connected from the wallwart do I need a diode to prevent flow to earth ground.  Thanks for any help that you can give.

The outside of the barrel jack and pin 5 of the serial port are electrically connected, it will work fine.  In point of fact, I connect my earth ground to the barrel jack for the TMCC buffer I'm building.

How do you connect the barrel jack to an earth ground?  Since I will be using the TMCC to run conventional locomotives I don't think I need to use the serial port.

Well, I connect it with a jumper plug that has a male and female 2.5/5.5mm connectors.

Is there an example you can direct me too?

HI GRJ.....thanks....you have already been very helpful.  So kindly confirm.

I can connect the walwart output wires to the inside and outside of the barrel jack without polarity concerns....and I can connect the earth ground from a different plug to the outside of the same barrel jack without an inline diode to prevent flow from the walwart output to the earth ground.

I am trying to mimic the original lionel TMCC base power supply and avoid using the serial port ground if at all possible.

Thanks for your patience.

You certainly don't want a diode anywhere near this mix, a plain connection from the outside of the barrel to the earth ground.

However, this is an important point.  The power source you use MUST be totally isolated from the layout, it can't be used for anything else.  Also, the primary and secondary of the AC supply must be totally isolated from each other.  Most are, but it's never a bad idea to mention this.

Thanks GRJ....much appreciated.

GJB - can you explain how you do that?  I need to avoid using the serial port as well.

FYI, I found the following 3-prong wall wart that could replace a dead command base wall pack if you have one.

https://www.allelectronics.com...l-transformer/1.html

Hi Railfan....I am by no means an expert here as you are no doubt able to tell....GJR and ADCX ROB are the real guys to check with.  Here is what I have done so far.  I have an AC to AC wall plug transformer rated for 12 V AC output and 450 MAmps....Per ROB the TMCC base only requires 100 Mamps so this wall transformer should work and does power the unit.  I did have to change the barrel jack plug to a barrel Jack that fits the TMCC base port.  I also have an earth ground wire from another separate 3 prong socket plug which needs to be connected to either the TMCC serial port (pin 5 per ROB) or the outside barrel jack.  

I was asking GRJ if I needed a diode(his answer was no) in the earth ground line since one wire of the AC wall transformer is also connected to the outside barrel of the jack.  I haven't hooked the ground to the wire leading to the outside barrel yet and to be honest...I am still a little afraid to do that.  However, I noted that there are only two wires leading from the OEM lionel wall plug to the barrel plug and they contain the stepped down AC power and the AC ground signals so this makes sense.

I hope this helps, but please recognize that I am learning here too.  

NNJ Railfan posted:

GJB - can you explain how you do that?  I need to avoid using the serial port as well.

FYI, I found the following 3-prong wall wart that could replace a dead command base wall pack if you have one.

https://www.allelectronics.com...l-transformer/1.html

Good find on the transformer, looks like you could just wire the ground to one of the secondary outputs and do the trick, just make sure that's on the outside of the barrel connector.

I do it by using a cable with a connector and the other is a solder connector.  That one gets an extra wire from the outside barrel connection to my "earth ground" on the TMCC Buffer.

@NNJ Railfan posted:

GJB - can you explain how you do that?  I need to avoid using the serial port as well.

FYI, I found the following 3-prong wall wart that could replace a dead command base wall pack if you have one.

https://www.allelectronics.com...l-transformer/1.html

@gunrunnerjohn posted:

Good find on the transformer, looks like you could just wire the ground to one of the secondary outputs and do the trick, just make sure that's on the outside of the barrel connector.

I do it by using a cable with a connector and the other is a solder connector.  That one gets an extra wire from the outside barrel connection to my "earth ground" on the TMCC Buffer.

Amazingly, almost 4 years later, the transformer mentioned above still appears to be available.  @NNJ Railfan, did you get one, and did it meet your needs?

One further question for the electronics gurus -

As mentioned in my other thread, the power supply for the Legacy Cab1-L set 6-37147 (base is 6-37156) outputs 9v AC, while the one mentioned above outputs 12v.  Would 12v work for the 6-37156 base?

@Mallard4468 posted:

Amazingly, almost 4 years later, the transformer mentioned above still appears to be available.  @NNJ Railfan, did you get one, and did it meet your needs?

John posted information regarding a suitable substitute on your other TMCC power thread.

https://ogrforum.com/topic/tmcc-power-supply

@RickO posted:

John posted information regarding a suitable substitute on your other TMCC power thread.

https://ogrforum.com/topic/tmcc-power-supply

Thanks, but I started that thread and it turns out that much of the information was in this thread, so I posted the latest question here.

Also, although less expensive, the item that John pointed to would require a separate ground, while the one from allelectronics.com already has a ground plug and external terminals, which appear to make it easier to wire for TMCC (per John's reply that was quoted in my post).

Also, the one posted by John also outputs 12v, so the original question about 9v vs. 12v still stands.

@Mallard4468 posted:

Thanks, but I started that thread and it turns out that much of the information was in this thread, so I posted the latest question here.

Also, although less expensive, the item that John pointed to would require a separate ground, while the one from allelectronics.com already has a ground plug and external terminals, which appear to make it easier to wire for TMCC (per John's reply that was quoted in my post).

Also, the one posted by John also outputs 12v, so the original question about 9v vs. 12v still stands.

I thought we were talking about the TMCC base, which is the title of this thread.  The TMCC base uses 12VAC, and was the adapter that I posted.  I would suggest in the future when you change horses, use a new thread with a descriptive title that matches the issue at hand.

I would NOT use 12VAC on the Legacy Command base.  Although I suspect it may work, you're pushing the power supply to deal with the extra voltage.  Given the fact that no more Legacy bases will be produced, I'd take care of the one I had.  Personally, I'd just order the transformer from Lionel, why take a chance for a few bucks?

@gunrunnerjohn posted:

I thought we were talking about the TMCC base, which is the title of this thread.  The TMCC base uses 12VAC, and was the adapter that I posted.  I would suggest in the future when you change horses, use a new thread with a descriptive title that matches the issue at hand.

I would NOT use 12VAC on the Legacy Command base.  Although I suspect it may work, you're pushing the power supply to deal with the extra voltage.  Given the fact that no more Legacy bases will be produced, I'd take care of the one I had.  Personally, I'd just order the transformer from Lionel, why take a chance for a few bucks?

Thanks - I agree with using the OEM power supply for Legacy if it's still available.  The fact that Lionel made the TMCC and Legacy bases look virtually identical (and included visually identical controllers) doesn't make sorting it out any easier.  (Edit:  p/n 6307156010 shows as unavailable on Lionel's website.)

Sorry that I caused confusion by starting that other thread - somehow this one didn't show up in my search.  But if you look at the first post in that other thread, I did ask about 9v vs. 12v for the Legacy and TMCC bases (item #3 in the original post), although I could have been more explicit.  (After 35 years in IT, I should have known better - I returned a lot of requests due to vague, ambiguous, or incomplete specs.)

Well, the "Legacy command Base" I have looks nothing like the "TMCC Command Base".

I will agree that the BASE1L and old BASE1 look identical except for color.

I still wouldn't use a 12V adapter on the BASE1L, I think you're playing with fire.

Legacy Command Base

TMCC BASE1 Command Base

TMCC BASE1L Command Base

@gunrunnerjohn posted:

Well, the "Legacy command Base" I have looks nothing like the "TMCC Command Base".

I will agree that the BASE1L and old BASE1 look identical except for color.

I still wouldn't use a 12V adapter on the BASE1L, I think you're playing with fire.

Legacy Command Base

TMCC BASE1 Command Base

TMCC BASE1L Command Base

Here's my packaging.  The prominent use of the word "Legacy" is very confusing to those of us who haven't used Lionel's command control and don't know all of the variations...

TMCC:

The box sez "Legacy" in large letters:

Aside from the small label on the base units (this one says "Legacy"), they look identical, but the "Legacy" base's power supply outputs 9v.

That is misleading as it's really a TMCC command base.  The only "bow" to Legacy is they have a special mode for the quilling whistle and it'll connect to the Legacy system and run trains in TMCC mode.