Bachmann Message Board

Discussion Boards => Large => Topic started by: jtputman on December 24, 2014, 12:03:45 AM

Title: Power Transformers
Post by: jtputman on December 24, 2014, 12:03:45 AM
A few years ago, I bought a White Pass & Yukon Big Haulers set in G scale. Last year, I bought a Durango & Silverton set in both HO and N scale. The power transformers appear to me to be identical. My question to The Bach Man is, am I able to use these power transformers interchangably? I am asking because I have a permant G scale layout in my basement Train Room, but like to do a temporary loop around the Christmas tree. I would be easier for me to use the power source from the HO or N scale set rather than swiping the one from the permanent G scale layout. Thanks in advance!  Jim

Title: Re: Power Transformers
Post by: Chuck N on December 24, 2014, 08:04:45 AM
What does it say on the back of the power supplies?  Large scale PSs usually top out at 18-22 volts.  HO and N rarely put out more than 12 volts.

There usually is a label somewhere in the power supply giving some minimal specifications.

Or you could just try the HO PS.  If it isn't suitable the "G" will not go very fast and the built in thermal circuit breaker will pop.  No harm no foul.


Don't use  the "G" PS with HO and N engines.  You might burn them out.

Starter set power supplies in "G" are not very robust, minimal at best.  Usually, less than 1 amp output.  Most engines require between 0.5 and 1 amp per motor.  My recommendation is to get a more powerful power supply for your main layout and use the starter set "G" PS under the tree.  Most of us recommend a 10 amp or larger PS.  If you are never going to expand with smoke, sound, lighted cars, or larger engines with two motors, you could probably get by with a 3-5 amp supply.

Title: Re: Power Transformers
Post by: elroho on April 08, 2019, 02:05:51 PM
I have two Big Haul sets, a liberty bell and a Blue Comet.  Both came with 20 pieces of track and a 17 volt transformer.  I would like to add a gondola to carry a small toy for my children and expand the track. That appears to strain the 17 volt Lifelike, tyco, bachmann transformers.  Any suggestions as to how i can get more power to the track?

Title: Re: Power Transformers
Post by: Loco Bill Canelos on April 08, 2019, 04:30:29 PM
Hi it is best to look at the AMPs .    A power pack/supply with a two amp rating will be fine for adding a few cars or to swap between layouts. As Chuck says if you plan to expand, the higher the amps the more you can do.  I have found that an HO power Pack rated at two amps seems to work OK for one 4-6-0 and even the addition of a second 4-6-0 plus the car ltrack power lighting.


Title: Re: Power Transformers
Post by: elroho on April 09, 2019, 10:43:36 AM
Do you mean that I should be ok using a 12volt 2 amp transformer for my g scale.  Will therein move?

Title: Re: Power Transformers
Post by: Len on April 09, 2019, 11:38:20 AM
I would look for an MRC 1370 (Model AA370) power pack to run your G starter sets. It has a 15VDC maximum output, and more than enough current handling capability for G starter sets. When my repair shop was open, the LHS I was colocated with used MRC 1370's to operate their Chrismas season G display layouts with no problems at all. The original MSRP was around $70, but you can find them on line for $40 - $50. Sometimes less. They also have an AC accessory output for building lights, etc.


Title: Re: Power Transformers
Post by: Loco Bill Canelos on April 09, 2019, 10:29:51 PM

Well at 12 volts, you would probably get more than enough speed for your G Scale 4-6-0 with four or five cars.   On my MRC 2 Amp power pack I rarely exceed 12 volts.  My pack will run Three 4-6-0's when triple heading with 6 well lubed cars.  They draw 1 and a half amps when running at 12 volts.  They do draw about the full 2 amps when starting then settle down to the 1 and a half amps.  The pack does put out about 18 volts, but under full power I would likely derail the train on my sharper curves.  I more often use my 10 amp power supply when Triple heading.  I most cases I double head tho.

Having said all that, most power packs I have seen that are 2 amps or higher do put out 15 to 18 volts.  If you have a need for speed then the higher the volts at the top end will give you that is important to you.  In my own case I prefer more prototypical speeds, rarely do I exceed 9 to 12 volts when operating depending on the number of cars being pulled.

On thing about the train set Bachmann Transformers is that they have Thermal protection and when the load gets to great they blow and the loco will stop.  After a time when it cools down it automatically resets, and the loco will run again.  There is a downside to this.  If it happens a lot the thermal breaker will weaken and blow at lower and lower loads til it fails completely.  A good two amp or greater MRC power pack/transformer should do fine for your described method of operation.  As Chuck said the greater the load and if power hungry accessories are desired then go high on amps if you are going to use only one power supply/transformer.  When in doubt go with higher amp levels.

All the best and enjoy your sets!!