Transformer question

[jscola30]

I was wondering, I have to keep 2 AC transformers (a mid 90's Lionel 40 Watt transformer and an MTH Z750) for use on my layout. The Lionel one can do the postwar equipment, the MTH one is needed for modern locomotives with bells. Can I keep both powered on and connected to the tracks safely (of course assuming I don't use both at once)?

[phillyreading]

Do you have more then one main track? If not then use one transformer at a time or you may put too much power to the track or damage the lower powered transformer. Also you should have more then a 40 watt transformer as that will barely run a postwar engine.

[lionelsoni]

All transformers are AC transformers.  Not all model or toy train power supplies are transformers, even if they put out AC and certainly not if they put out DC, although almost all of them have a transformer inside as a component.

Most actual transformers with variable-voltage outputs disconnect the output when you put the voltage control into its lowest position.  (Some American Flyer transformers are a little different.)  You can leave two of these wired to the track if you use only one at a time, since the other one, not in use, will be disconnected in that way.  If you make a mistake and turn both up at once, their circuit breakers should protect them, regardless of their relative sizes.

Whether your two "transformers" are really transformers, I cannot say, not knowing what is in them.  So I can't assure you that they can both be safely connected and powered at the same time.  But, in any case, you can certainly safely connect their commons permanently to the outside rails, leave both of them powered all the time, and use a single-pole-double-throw switch to select which one is connected to the center rail.

[sir james I]

If in doubt disconnect one wire from the unused transformer that would take it out of the circuit. Or use the switch mentioned above.

[jscola30]

These are the ones I have

http://www.lionel.com/products/finder/ProductDetail.cfm?ProductNumber=6-12885&expandBranch=0&Keywords=&CategoryID=116&RailLineID=&CatalogId=

http://www.mthtrains.com/content/40-750

It's just a simple loop, one throttle would always be at 0.

Believe it or not, the older Lionel 40 watt puts plenty of power. The newer MTH one barely nudged the small Hudson I have, but the 40 watt powers it with three lighted postwar passenger with plenty left over. (If you are looking at the picture, to get the train running at a good speed requires it to be put at just the end of the green zone). I bought the MTH one to take the place of a CW 40 (heard the earlier CW 80s had problems) which couldn't handle dual motor locos. It seems I'm looking at the "de-evolution" of smaller, introductory sized transformers 

The older Lionel one I would do for everything except that it does not have a bell control (it will power dual moto locos just fine as well).

Honestly, this is all for my laziness  maybe I'll clean things up, rig something up where I can more easily unplug one.

[rtraincollector]

I wish you luck with the lionel transformer they where know to be a problem. they get to where they will trip the breaker real easy ( basiclly breaker gets weak ) never tried to replace the breaker I just threw themaway. Now I have a poweCW-40 ( which I'm not inpressed with either it has a hard time running my single motor post war steam engines let alone a dual motor engine, the CW-80's are fine now as long as you don't buy and old used one. ( I would think thou by now most of them are gone ) But sure theres still a few out there.

The MTH I have no knowelage about. Never had one or used one.

Hope all works fine for you for a long time. I'm sure there are some good ones of that lionel transformer and hopefully you have one

[jscola30]

yea I think I got this as a birthday gift to power up the first train I had in 1995 I think, and it's been fine ever since. Like I said, too bad it didn't have a bell control/too bad I started buying engines that had one 

[M. Mitchell Marmel]

Oh, well, that's easily fixed! 

http://www.ebay.com/itm/Lionel-Sound-Activation-button-6-5906-with-instructions-/151320450865?pt=Model_RR_Trains&hash=item233b66d731

Just hook that up and voila!  Bell sounds!  :D

Mitch

[jscola30]

I know it's weird to bring this topic up again, but I was puzzled why a 40 watt transformer would perform so much better than a newer 40 and 75 watt ones. Well, I looked again, my mid 90s Lionel transformer is not a 40 Watt, but a 77 watt one. It is remarkable though, the Lionel one only being 2 wattages (?) higher than the MTH (and is older) performs way better. I have a post war small hudson with light (it's the one from 52 w/o Magnetraction that uses the Berk's shell) with three passenger cars, all lighted. MTH one barely nudged it, Lionel one not only moves it well, but there's room to spare. However, I will say, the MTH one does work better with certain modern locos (smoother, better low speed range), as with  the Lionel one there's  2 speeds: 0 and 1 million,.

[ADCX Rob]

jscola30

Well, I looked again, my mid 90s Lionel transformer is not a 40 Watt, but a 77 watt one...

Well, yes and no. Your transformer is a 3 amp controller powered by a wall-wart AC adapter which itself draws 77 watts from the wall. There is only 3 amps available at the controller output.