I have an older AHM powerpack for my Ho trains and it doesn't put out eno power to run two engines at once. (It is putting out the posted DC voltage according to my Voltmeter however). so I want to hook two powerpacks together to double the output. I have experimented with this using aligator clips and the engines run fine. The question is: how can I rewire the powerpacks in series (?) so I can use both to double the power to the tracks, and use just one forward/reverse and speed controller?
Hi!
When you say "double the power", I assume you are talking of amps, and not volts.
Assuming that's the case, I'm not sure I would mess with it, and concentrate on getting a new powerpack. I also assume you are running DC (not DCC), and MRC has a few that will give you plenty of power. In fact, their Controlmaster 20 puts out 5 amps, and I had two of them on my previous layout. Note they were not connected together - they were used to run separate trains.
I'm sure the electrical gurus on this forum will have advice on what you could do with what you have - if it can be done safely.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
Save yourself alot of trouble and purchase a larger power pack. They can be had for very little brand new off ebay. You will find the newer packs to be much better with alot more control of you trains.
Bob
tam I have an older AHM powerpack for my Ho trains and it doesn't put out eno power to run two engines at once. (It is putting out the posted DC voltage according to my Voltmeter however). so I want to hook two powerpacks together to double the output. I have experimented with this using aligator clips and the engines run fine. The question is: how can I rewire the powerpacks in series (?) so I can use both to double the power to the tracks, and use just one forward/reverse and speed controller?
If you wire the power packs in series, one of two conditions occur, depending on the setting of the direction switches (which sets the output polarity) relative to each other. In one case, the voltages add. In the other they subtract. You cannot change the direction of the locomotive by changing a single direction switch - you would have to change both at the same time. The speed of the locomotive is going to be a complex sum or subtraction of the power packs' output voltages which will be determined by the throttle settings, the relative settings of the direction switches, and the current drawn by the locomotive.
Wiring the power packs in parallel feeds the output of one into the other power pack, and sets up the likelihood of destroying one or both power packs. The greater the difference in output voltage between the two power packs, the quicker the destruction. My old AHM power pack has no short circuit or overload protection that I could find.
Overall, either is a bad idea. To control 2 engines running together, get a power pack big enough to power both at once. Note that the engines have to go in the same direction and similar speeds at all times.
Or set up a block system to control the engines independently of each other, one engine to each power pack.
my thoughts, your choices
Fred W
Save yourself a lot of possible trouble by buying a power pack with the power you require.
I had to do that some years ago. The two different power pack solution is trouble.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
New DC power packs are not that expensive, I would just buy a new Power pack. The "oldies but goodies" are not always that "good".
This question might also get better responses posted on the "Electronics and DCC" forum here, not the general forum.
-G .
Just my thoughts, ideas, opinions and experiences. Others may vary.
HO and N Scale.
After long and careful thought, they have convinced me. I have come to the conclusion that they are right. The aliens did it.
Another vote for, "Get a new power supply with the capacity you need." Use the little old wimp to power building lights or Tortoise switch machines.
I have a large DC controlled layout, and sometimes run a single train with three big open-frame motors. Because of that, I've arranged to use interchangeable, plug-in power packs. A little pack lie yours is adequate for the Spectrum 0-6-0T I use for a yard switcher at the colliery. A road train might get a Tech-II or a recycled Tenshodo pack with a modern silicon rectifier (replacing the old stack-of-dishes selenium unit.) My 3 amp home-built is reserved for doubleheaded steam with a train of lighted passenger cars.
When it comes to powering analog DC locomotives, it's always better to have more power than you need - in the single power supply connected to that particular train.
Chuck (Modeling Central Japan in September, 1964 - analog DC, MZL system)
Thanks for the advice..do you have any brands you'd recommend?
Just so we're unanimous - don't jury rig things and wire two packs together.
MRC's DC power packs have always been top notch and reliable. You generally can't go wrong. A Tech 4 260 or, if you have your layout wired to allow two power packs, the Tech 4 280 which is two throttles in one are probably your best options for current production stuff. A Tech II 2500 would work great if you cna get one with some sort of guarantee that it still works. They were good units when new but not everyone takes care of their stuff so a used one would be a bit of a gamble.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I might as well throw in my (it doesn't buy much any more anyway) and echo what the others have said. Don't try to run two power packs together, that's just asking for trouble. MRC is a good brand of throttle. They have them with different current ratings and different features like pulse or momentum. I've got two of them and they're really good.
..... Bob
Beam me up, Scotty, there's no intelligent life down here. (Captain Kirk)
I reject your reality and substitute my own. (Adam Savage)
Resistance is not futile--it is voltage divided by current.
Buying a new power pack to get the power you need is the right choice.
The old units may be used to drive turnouts or a turntable, or to power structure lights and streetlights. Or, you could have the luxury of a powered test track on your workbench.
It takes an iron man to play with a toy iron horse.
This is somewhat dangerous. If your powerpacks are hooked is parrallel, you run the risk of possibly ruining one, both or even starting a fire.
Here's how this can happen:
Lets say you turn the dial on #1 to put out 10 Volts
You turn the dial on #2 to put out 3 Volts
The difference between the two is 7 volts. Electricity will run from power pack one into power pack 2. Since there is very little resistance between the wires, you are running a very high amp rate which will damage power pack #1 and possibly #2.
If you run them in series, you are doubling voltage and not current. Most motors max out at 12 V which any power pack an handle. And not all power packs can handle being wired in series.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
THANKS TO EVERYONE FOR THEIR ADVICE AND SUGGESTIONS. Obviously the easiest thing to do is to buy a new powerpack. Unfortunatly the value of my RR stock is down due to the recession and the company treasurer has frozen all purchases until next year.
Having two powerpacks (and a cheap treasurer who may be replaced at the next board meeting by S. Claus) had been to take the output terminals of both transformers, wire the leads to an input for the speed and direction control on one of the powerpacks. This I felt would give me the double power I need but retain a single speed controller and forward/reverse switch. Reading most of the replies indicates this isn't a feasible way. Oh well!
Thanks for all your help