Just wondering if it is possible to hook up an operating accessory with control rail and so on (145 gateman) using another transformer other than the one you use to actually run the train? Can you use the fixed voltage of another transformer and tie into the ground of the one running the train and have it operate properly. My goal was to use my ZW for track power and switches only. Hope I haven't had to much eggnog and this makes sense. Thanks and Merry Christmas!
Transformers must be in phase to do this.
In other words the ground side of both your transformers must come from the ground side of your AC outlet.
Dave632Transformers must be in phase to do this.
This is one way to do it, but there are inherent advantages to having the transformers out of phase, especially with very large, power hungry layouts. AND, if you are just running accessories from a separate transformer, whether it's in phase or not doesn't matter. That they share a common return is, however, important for accessories that use isolated/insulated running rails for activation.
Dave632In other words the ground side of both your transformers must come from the ground side of your AC outlet
This is irrelevant as the toy train transformer secondaries are isolated completely from the primaries. There is no reliance whatsoever on which side/phase of the AC mains is associated with phase-wise with the common output of the transformer.
There is a good tutorial on transformer phasing HERE. It shows a ZW and a ZW controller but is entirely relevant.
Rob
Real quick...I just received a 145 gateman today and wanted to test it. I believe it was hooked up right but when I powered the track up the gateman came out. Do I need to insulate the ties on the section of track I have the fiber pins also?
Yes, as the ties are conducting power from the side w/ the steel pins, which in turn are connected, electrically, to all of the running(outside) rails on the layout.
Rob I appreciate the knowledge. Should I just take some insulated pieces off some old track or what do you recommend? Thanks again.
That actually is the preferred method.
I've also used black sand paper instead of the track isolation pieces .... works fine.
Black sandpaper or Emory cloth will all work, and as long as re-crimping the ties doesn't cut through the material it will work fine. The problems come up when something too thin is used and the sharp metal edges cut in and contact the rail, defeating the intended job of the insulation.
One more thing for today if I may. The gateman is working properly on my little test track but i assume the wheels sparking isn't right? Any thoughts? Perhaps I did not completely isolate the rail. I downloaded the service manual for a modern gateman thinking there pretty much the same so I think it's wired up right.
Wheels sparking is correct. They are the "switch" activating the gateman. Clean wheels & track will minimize sparking.
Thanks a million!!!!
ADCX Rob Dave632Transformers must be in phase to do this. This is one way to do it, but there are inherent advantages to having the transformers out of phase, especially with very large, power hungry layouts. AND, if you are just running accessories from a separate transformer, whether it's in phase or not doesn't matter. That they share a common return is, however, important for accessories that use isolated/insulated running rails for activation. Dave632In other words the ground side of both your transformers must come from the ground side of your AC outlet This is irrelevant as the toy train transformer secondaries are isolated completely from the primaries. There is no reliance whatsoever on which side/phase of the AC mains is associated with phase-wise with the common output of the transformer. There is a good tutorial on transformer phasing HERE. It shows a ZW and a ZW controller but is entirely relevant.
To check and see if you are in phase with older transformers simply wire both transformer grounds together then hook a lightbulb between both variable outputs turn on the power. If the light does not light you are good to go, if the light lights you are out of phase and need to reverse one of the plugs.
Yes primary and secondary's of transformers are isolated but it is not irrelevant in relation to ground.
Both transformers must have the same ground reference or the out of phase condition will cause problems.
Dave632Yes primary and secondary's of transformers are isolated but it is not irrelevant in relation to ground. Both transformers must have the same ground reference or the out of phase condition will cause problems
Both transformers must have the same ground reference or the out of phase condition will cause problems
That's all on the secondary side. There is no reliance whatsoever on which side/phase of the AC mains is associated with phase-wise with the common output of the transformer(s) - it could be hot or neutral - it doesn't matter as long as they are matched(phased). If we were talking autotransformers, it would be a different story.
As Rob said, there is a slight advantage (reduced voltage drop in the outside rails) to having an accessory transformer out of phase with the track transformer; but it will work either way--in phase or out of phase, or even with AC on the track and DC on the accessory, or vice-versa.
A transformer with a polarized plug can of course be plugged in only one way. But this does not guarantee that the outputs of two transformers are in phase. The manufacturer(s) may not have wired the two transformers in the same way. Furthermore, the outlets in an American house are not even all in phase with each other. Even the two sockets of the usual duplex outlet may be wired to opposite phases of the utilization voltage reaching your house, using what is called a "three-wire" circuit.
Wiring track blocks in phase is a good idea, to reduce the chance of fireworks when trains accidentally cross a gap from one phase to the other. But in-phase blocks from separate transformers or, even worse, multiple outputs from the same transformer, should not be used deliberately as a way to get from one track to another.
Bob Nelson
ADCX Rob
I don't think we are understanding each other. The site you referred to is stating exactly what I am indicating.
If you are saying that either the hot side or the neutral side of the ac input can be used for transformer input as long as both are the same then yes that will work but both transformer inputs have to be hooked up the same way.
By phasing I am talking about the output sine wave of both transformers being in sync and not phase shifted as they would be if the input grounds were reversed.
I am NOT talking about the secondary neutrals being hooked together properly as that is not phasing.
Look at the site you sent me to he is saying the same thing I am.
Do the simple test that is indicated on that site. With both neutrals tied together and hooking a meter or a light bulb to the positive terminals and adjusting both to 10 volts there will be little voltage or light when in phase. When out of phase the light will be bright and the meter will indicate a voltage just as the site says. I tried it just to double check myself.
Dave,
I've been phasing transformers for layouts since I was eight, there's nothing wrong at all with your method and I use it all the time(most recently on my Christmas layout - 1948 ZW phased with a PM-1 and a RS-1. I think the confusion is that you keep making a reference to ground. There is no ground on the secondary side of the circuit. Common, yes. Chassis ground on an individual item, yes, perhaps.
You said "Both transformers must have the same ground reference or the out of phase condition will cause problems".
It just so happens that the neutral is supposed to be tied to ground at the household breaker box(it's not always - due to error or omission or otherwise)... but this is all on the primary side of a toy train transformer. When switching/turning our plugs for "phasing", we are actually swapping hot for neutral. This is where the "phasing" aspect comes in with reference to our trains.
There is a clear distinction here because, believe it or not, many(but fewer every day) folks live in dwellings that still do not have "grounded" outlets whether by a ground conductor in Romex or by metal conduit.
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