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Need some suggestions regarding a power issue.  I have a fairly large layout with a significant number of lit buildings and animated accessories.  I have a MTH Z400 that I am using to provide track power.   I also had a 500 watt Z Controller set at 14 bolts to power all my accessories.  It is no longer big enough.  Even the 14V connection on my Z4000 does not provide enough power.  I took my dad’s out of Lionel KW to a local Lionel Authorized Repair Shop.  He did what he could.  He told me that the windings are starting to breakdown.  It worked for about 20 minutes before for the overload kicked in.  I connected a multimeter inline.  It stated the current draw was 6.3 Amps.  I am trying to figure out what to do.  Buy a 200 or 300 watt 14V landscape lighting transformer to power my accessories or pickup an old rebuilt zw power supply like my dad’s old kw.  Any suggestions?

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If you have a local hobby shop that does trains, most usually have quite a few transformers either used, or that came with starter sets...usually for around $5-$15.  

I bought a $13 90 watt Lionel 1033 for 16 volt duty, and an old AmericanFlyer 100 watt transformer for about the same.  This powers accessories that like 11-12 volts.  If you're concerned about using only D.C. for "sensitive" LEDs without bridge rectifiers, an HO gauge transformer may be just the ticket.  


@Roeschs1 posted:

...I took my dad’s out of Lionel KW to a local Lionel Authorized Repair Shop.  He did what he could.  He told me that the windings are starting to breakdown.  It worked for about 20 minutes before for the overload kicked in...

I'd bet that the only problem with the KW is the breaker. They are notorious for failing just as you describe... there is no way a 6.3 amp load should trip a proper working breaker.

I wouldn't mess around with old computer power supplies.  They require a load to function correctly.  For about $20-30 you can find regulated 12VDC power supplies (UL listed) that will provide safe, constant power.

I would also recommend splitting your lighting up and running it on DC.  If you use LEDs, you can power a whole bunch of lights off 1 power supply.

Keep your AC power supplies for those accessories that absolutely require it.   A good AC accessory transformer is the K-Line PowerChief 120F (if you can find it - they go for $50-80).


Well, my PC power supplies have been working flawlessly for six years. They has a 5 volt tap that , with a diode, is running all but one of my Miller signs. They also have a lightning fast electronic breaker that protects the 24 to 26awg wire that I use in buildings. You can hardly buy a breaker for the price of the unit, especially if you salvage one from an old computer. While there are some that require a load, these work fine without. If one is needed, a resistor is all that is needed to supply it. I am just offering this as my own experience with this method There are certainly many other ways to skin this cat.

If you can operate most/all of your accessories on DC, that is the direction of all things electronic.  There are vibrating accessories that required AC voltage and a few electro-mechanical mechanisms (e.g., crane) that depend on AC.  But most modern accessories, even those that don't say explicitly state "AC or DC compatible" will operate just fine on DC; the manual has not updated.

Obviously if you have a spare AC-output transformer then you cost is "free."  But I use a simple rule of thumb for accessory power - don't pay more than 10 cents per Watt.  Here is a recycled photo from a previous OGR thread.

ac dc brick comparison with inset

You can get a 90 Watt DC-output laptop charger for about $10 shipped on other words about 10 cents per Watt.  The one shown above has a switch selectable output voltage for 12V, and up.  You might find the "standard" 12V DC fixed output from a computer/PC power supply may not be enough for certain O-gauge accessories.

90 watt dc output for about 10 cents per watt shipped

While O-gauge layouts are generally not restricted to maybe size does not matter...but note the size/weight difference between a traditional iron/steel AC-to-AC transformer vs. an electronic AC-to-DC transformer. 

One advantage of train transformers is they pretty much all have "simple" red and black terminals/jacks.  OTOH DC-output power sources meant for computer or non-train applications have connectors that may be completely foreign to what is used in O-gauge.  There are adapters and "break-out" connectors for this and should be a consideration if splicing, wiring, etc. are not in your comfort zone.


Images (2)
  • ac dc brick comparison with inset
  • 90 watt dc output for about 10 cents per watt shipped

There is also a very low-price alternative to dedicated, hi-output DC power needs that work for me by only using one per-accessory. For instance, for a Walthers (noisy as heck) oil well pump accessory, I just found a 9V wallwort for 2 bucks at a local Sally Ann, cut the end off of it and attached it to the leads from the oil pump. Works great for years. Also did that for a couple of other accessories that run on DC, but am still in the past when running lights - I use a dedicated old Marx transformer w/ 1 variable and one non-v. at 14 volts AC. for 2 Lionel accessories - again, works oil well JPGBowel oil company


Images (2)
  • an oil well JPG
  • Bowel oil company

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