2 ph 180+ tpc 400?

I don't think they are both turned on, but probably the turned on one is lighting the pilot led of the off one by transformer action of the off one to its led. That's normal, or at least not a problem.

i listened to the 60 hz hum it comes from both even when i switch off one of the transformers the light and hum are there.

That's not conclusive. If you draw more than 10 amps...like say 15, and the one that is turned on trips out, then it's the only one that is on.

the transformer that is turned off gets as warm as the one turned on, so they are both on even with one transformer turned off.

Ok...I'm gonna hang in there...here's a schematic of the 180 watt Powerhouse (probably the 135 watt as well) so you can see how the "on" Powerhouse can drive the off Powerhouse when their outputs are connected together, light the "off" led and warm up the "off" transformer with core losses...even though the "off" Powerhouse is off.

 

(The diode in the photo is not stock, it is something I added to one of my Powerhouses when I replaced the switch after the original led burned out.)

 

You are driving current into the second transformer, I suggest you either turn it on or disconnect it.  It's not doing you any good, that's for sure.

Gunrunner john is correct you are back feeding the second transformer and creating 120 volts on the primary. If the plug was disconnected on the second transformer it actually would be live. This can be a dangerous condition. Do not run one tranformer by itself without disconnecting the second one from the TPC. Transformers work in forward or reverse.

Ron

these answers do make sence! why does lionel not warn of this condition? shouldn't they say when using 2-ph 180's make sure both are switched on, even if the red light is on the transformer may be off.

I can only assume that the folks at Lionel didn't think anyone would have two connected and not use them.

 

While the answers don't makes sense to you, they are correct, you are simply transforming the 18V across the secondary back into 120V across the primary.

 

Remember that a transformer is just two windings, and it works as a step-down or step up voltage conversion device.  The transformer doesn't know what you intend to do.

gunrunnerjohn---what you say DOES make sence. its that lionel should comment on this possible situation.

Lou Kovach of IC Controls builder of the TPCs did comment on it when he first issued them and showed paralleled 135 watt units in his promotional video!

Figuring it's a potentially dangerous situation, they certainly should comment on it!  Someone that sees a plug out of the socket usually assumes it won't have 120V on it!

I don't think anybody thought of it in the beginning. Any time the light is on this means the primary winding is live whether it is plugged in or not. If the switch is in the off position there should be no voltage at the plug itself. If the switch is in the on position there would be 120 volts at the plug.

Ron

i have sent an e-mail to lionel about this yesterday. when i get a reply i will inform all of you.

Perhaps true, but remember that if this is connected into the circuit, chances are that the switch could be on.  It's not a 100% dangerous situation, but only 50%.  IMO, that's not acceptable.

Since the red light comes on the "off" one whether it's input is plugged in or not, that in itself is a warning.

 

 

 

I regard any 120 volt plug that's not plugged in and is hot to be a hazard, I don't really care if a red light is on somewhere or not!

Well the question was "is this normal?" The answer is yes.

 

But this thread has changed, so what would y'all think a solution would be to the danger of the many various ways someone would misuse this?

Well, the correct way would be to insure no feedback of voltage from the secondary to the primary.  Obviously, that's not going to happen with the current product.  Given it's a plain AC transformer, probably the most effective way would be a relay powered by the secondary to transfer power to the outputs.  No power on the secondary, no power to pick up the relay and connect the secondary to the outputs.  Like I said, this ain't gonna' happen with the current product.

here is the answer i got from lionel: "both would need to be switched off to completely cut power to the tpc".

 

it really doesn't answer any saftey questions or don't do (this or that). 

Sounds like a politician, answer the question you want to, not the one that is asked!