Autobus Prime wrote: Texas Zepher wrote:I used to have three toy slot car power packs (20VDC each) hooked in series in order to get 60 volts to power the plates on vacuum tubes. Ham?
Texas Zepher wrote:I used to have three toy slot car power packs (20VDC each) hooked in series in order to get 60 volts to power the plates on vacuum tubes.
Texas Zepher wrote: I used to have three toy slot car power packs (20VDC each) hooked in series in order to get 60 volts to power the plates on vacuum tubes. Looking back I am surprised the selenium rectifiers held up to the strain of 3X their normal load.
I used to have three toy slot car power packs (20VDC each) hooked in series in order to get 60 volts to power the plates on vacuum tubes. Looking back I am surprised the selenium rectifiers held up to the strain of 3X their normal load.
TZ:
Ham?
DigitalGriffin wrote: It is very important that they are putting out the same voltage, or you may have voltage flowing into a transformer that's supossed to be flowing out. It's a bit risky unless you are using DC with diodes. Even when voltage/phase matched, the only thing you are increasing is the maximum current.
Autobus Prime wrote: jeffrey-wimberly wrote: BigG wrote: If you need the extra power, get a single larger source. I agree. Get a larger power source that suits your needs. I almost burned my parents house down one time by attempting what your asking about. j-w:Do tell.
jeffrey-wimberly wrote: BigG wrote: If you need the extra power, get a single larger source. I agree. Get a larger power source that suits your needs. I almost burned my parents house down one time by attempting what your asking about.
BigG wrote: If you need the extra power, get a single larger source.
If you need the extra power, get a single larger source.
I agree. Get a larger power source that suits your needs. I almost burned my parents house down one time by attempting what your asking about.
j-w:
Do tell.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
Danger ! Do not do this !
You are asking for a whole pile of trouble if you couple 2 sources of energy together. If dealing with AC sources, you will likely cause fluctuating output that can blow the transformers if the phase of the output varies just a little because of what you are feeding. There is a fire risk here. With DC, the 2 outputs will fight for supremacy and one or both will suffer damage to their regulators. If you need the extra power, get a single larger source.
A comment on the metering procedure mentioned above, if I may. If you are going to meter between 2 different transformers, there must be a common connection of 1 of the wires of the output. A transformer isolates its output from the powerline so the outputs need that connection to give a reliable reading. Without that common wire, all you will read will be "leakage" voltage at very low current.
Please tell us what you are trying to set up. Perhaps we can help find a better way.
Have fun, George
T1938:
Hooking up two Transformers? Well, I don't know...is she cute?
By transformers, do you mean power packs/throttles that control trains or do you mean power transformers that step down 120 volts to 12 volts or some other safe voltage? If the latter, are you trying to connect them in parallel to get more power or series to get a higher voltage?
..... 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.
I assume you're planning to connect the outputs of the two transformers. This sets off alarms. Why do you want to do this? It's not good practice.
But, to answer the question, you can use a meter to check the polarity of the outputs. For DC, it's easy. If you put the positive lead (usually the red one) to the positive terminal, and the negative lead (usually black) to the negative terminal, the meter will read correctly. Reverse the leads, and the needle will try to go off-scale below zero.
For AC, set the meter to "AC" and you should see a voltage across the two terminals. In AC, what you might think of as "polarity" isn't strictly that any more, because AC "alternates" (hence the A in AC) sinusoidally between positive and negative. So, instead of polarity, we now have "phase." What you want to do is find the two outputs that are "in phase" with each other. If you put one probe from your meter on a post on one transformer, and the other probe on a post from the other transformer, you will see a voltage if the two posts are "out of phase" and no voltage if they are "in phase," assuming that the output voltage of the two transformers is the same.
If you don't have a meter, by the way, you can use a light bulb. It will still light either way on DC (no polarity information from a light bulb) and will light on AC only when the two outputs are out of phase.
Now, why did you want to do this again?
It takes an iron man to play with a toy iron horse.
Use a volt meter. Put it in it's proper mode (AC or DC voltage reading depending on transformer type) Connect leg to one terminal on the transformer #1, and the other on terminal on transformer #2. If they are in phase they should read 0 volts.
You can do the same trick with a light bulb. If it lights, then they aren't of the same phase.
It is very important that they are putting out the same voltage, or you may have voltage flowing into a transformer that's supossed to be flowing out. It's a bit risky unless you are using DC with diodes. Even when voltage/phase matched, the only thing you are increasing is the maximum current.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!