Multiple GW180s

If you're not running conventional, I'd stick with the Lionel Powerhouse 180 bricks.  I have four of them running my layout, they work great and have excellent circuit protection.  There's no reason to pay the premium for the BW180 if you don't need variable voltage.

Thanks John. I assume that a train that straddles two different GWs at the same time is fine?

My 1970s childhood layout had two loops that were connected by a pair of switches.  Each loop was powered by its own transformer.  My dad always reminded me to have the transformers set to approximately the same voltage when "crossing over" from one loop to another.  Also the transformers had to be "in phase," or sparks would fly (literally!)  These were iron-core transformers.  I would hope that when Lionel designed the GW180, they anticipated your use case but there's really no way to know for sure.

The best practice is to have each loop or track block connected through selector switch(es), so that any block can be powered from any transformer.  If you wire it this way, careful pre-selection of the power source will eliminate any chance of a train "bridging" an insulated gap between two different power sources, and feeding voltage from one transformer back into the other transformer's secondary.  My $.02.

Thanks for your input Ted.

Keith, I agree with John. I think the GW is just a 180W brick with a throttle to vary the voltage. You can run the 180W bricks right into the TIU and use the remote to vary the track voltage for a lot less money.

To directly answer your question, yes, you could use multiple GWs and have a locomotive span blocks controlled by separate GWs. No sweat.

Thanks raising4daughters(God bless!!)....I'm not running conventionally at all. No varying of track power. My question is for an entire DCC layout, do I need to be concrned when a locomotive is bridging two power districts(one roller on one side of the insulator and the other roller on the other) and I'm using Lionel Fixed voltage Powerhose bricks for both of those districts?

@raising4daughters. Sorry I missed your answer that I do not need to worry about phasing with two seperate bricks and that DCC trains can occuly tow seperate bricks at the same time(one roller on one brick and the other roller on the other brick. Much appreciated.

@Maxandy posted:

@raising4daughters. Sorry I missed your answer that I do not need to worry about phasing with two seperate bricks and that DCC trains can occuly tow seperate bricks at the same time(one roller on one brick and the other roller on the other brick. Much appreciated.

DCC or DCS?

I love being a repair guy when these topics come up.

Sure, don't phase your multiple transformers, no you don't worry, nope, won't cost you hundreds if not thousands of dollars...........

And someone will say but, but, but......

Your money, your time, your hobby.

@John - I'm going to use MTH TIU(currently)and Lionel base 3 when it comes. No conventional running.  I had assumed this was generically called DCS. I will be using the Lionel bricks to provide power. I was origanally concerned about a locomotive that crosses from one power district to another and in doing so is momentarily across two diffetent Lionel bricks . I had heard about phasing and I did not know if under these circumstances(fixed power, no conventional running, same power bricks) that I need to be concerned. Many thanks.....

Any time 2 transformers are used on a layout and there is any common between them- then phasing applies.

Again, it's a simple concept. You have 2 transformers. If they are in phase- the output voltage cancels out to 0V between 2 districts.

If you mess up and don't ensure they are in phase- the 2 transformers ADD on each other and create 18+18V or 36V across the power districts or wiring points.

Being trains have a listed warning above 19V- what do you think 36V or more does to pretty much any train electronics- but also just even basic electrical parts-wires, pickup rollers?

I cannot stress this enough. The INSTANT a person begins using 2 separate wall plugged in transformers on a layout- VS one large transformer with built in multiple outputs- you likely invoke the risk of an out of phase high voltage situation somewhere on the layout or in your wiring.

This is because both the track and many accessories all depend on this concept of "common. Because when you have 2 power sources- and both are connected to "common" (possible in ways through accessories or devices you didn't know share common)- again the risk is, unless the transformers are in-phase- somewhere in all that wiring, somewhere on the layout the voltages ADD instead of cancelling out.

If there is any lesson to be learned- that's it right there as simple as it gets. If you use or buy one large transformer with multiple built in outputs (ZW-L, Z4000, MRC Pure Power) they are purpose built transformers with one core- so all the outputs by design are in-phase and thus severely limiting the possible chance of high voltage (greater than 18-19V) somewhere in wiring or tracks or contact points.

Again, when you introduce multiple transformers, there is no guarantee that even 2 identical units side by side are in-phase. Manufacturers have gotten sloppy over the years and it's well documented in forums about how 2 identical transformers- side by side, plugs the same way- are wired internally out of phase and yes- this applies to big L 180W powerhouse bricks- and thus anything that uses those bricks.

I see multiple layouts using multiple Lionel 180 Watt bricks. Trains have to pass across power boundaries. How do you phase when your using multiple bricks? I really do get the phase issue but how do the folks using multiple Lionel bricks to power different sections of the layout do it? Thanks for your time and the guidance.

@Maxandy posted:

I see multiple layouts using multiple Lionel 180 Watt bricks. Trains have to pass across power boundaries. How do you phase when your using multiple bricks? I really do get the phase issue but how do the folks using multiple Lionel bricks to power different sections of the layout do it? Thanks for your time and the guidance.

https://ogrforum.com/...power-houses-phasing

Video https://www.youtube.com/watch?v=iASQfnE6pCk

@Vernon Barry posted:

Again, when you introduce multiple transformers, there is no guarantee that even 2 identical units side by side are in-phase. Manufacturers have gotten sloppy over the years and it's well documented in forums about how 2 identical transformers- side by side, plugs the same way- are wired internally out of phase and yes- this applies to big L 180W powerhouse bricks- and thus anything that uses those bricks.

No doubt, it's good advice to check phasing on any multi-transformer layout.

Can you explain how (if?) phasing and polarity are related? I recall reading that this was harder to distinguish with older PW transformers because prongs were the same size. With newer/modern transformers (and most modern appliances), one prong is larger than the others.

I thought I recall reading (on the internet, so it must be true) that modern Lionel 180W bricks would be phased automatically since you can only plug them in one way to an outlet. Sounds like you'd suggest not trusting that advice.

I'm about 90% done with basement layout 2.0 and have 3 Lionel 180W bricks powering 3 separate power districts (two mains, a yard) through a DCS TIU. Trains will traverse all the districts. Sounds like you'd recommend verifying phasing (which is a fairly simple thing to do as I've done in the past with conventional layouts).

Thanks in advance. I think your answers to my question will also help the OP.

@rising - Based on your reply, you currently use multiple 180s to power different sections. It sounds like you connected their grounds together and sent a power wire off to whatever power district you wanted to support. It seems like you did that out of the box with no phasing. Am I reading that correctly? Thanks for your input

@raising4daughters posted:

No doubt, it's good advice to check phasing on any multi-transformer layout.

Can you explain how (if?) phasing and polarity are related?

Polarity is often associated with DC- however, you mentioned DCS- the MTH protocol and signal. The problem is that DCS even though on AC power- has a DC component to the signal and thus PS2 engines specifically are DCS signal polarity sensitive. PS3 is not, but PS2 is. This can lead to problems on a layout where MTH DCS signal is used and the convention that the red posts of the TIU channel outputs are not connected to the center rail of 3 rail track. In other words, again, it's AC going into the TIU and AC coming out of a TIU channel, however, the DCS signal is polarity sensitive, so if you swap the output wiring to the track- a PS2 engine will not work in DCS but PS3 will- leading to much confusion for the owner.

Phasing is different and happens at the transformer. The transformer is the power source, the TIU is a source of DCS signal.

I recall reading that this was harder to distinguish with older PW transformers because prongs were the same size. With newer/modern transformers (and most modern appliances), one prong is larger than the others.

I thought I recall reading (on the internet, so it must be true) that modern Lionel 180W bricks would be phased automatically since you can only plug them in one way to an outlet. Sounds like you'd suggest not trusting that advice. No, sadly wish this was not true but it is- you CANNOT depend on this fact that they were all built in phase with the plugs.

I'm about 90% done with basement layout 2.0 and have 3 Lionel 180W bricks powering 3 separate power districts (two mains, a yard) through a DCS TIU. Trains will traverse all the districts. Sounds like you'd recommend verifying phasing (which is a fairly simple thing to do as I've done in the past with conventional layouts).

Thanks in advance. I think your answers to my question will also help the OP.

Thanks all for time and guidance

Wow,  this is a very helpful topic and perfect timing for me.  Today I just hooked up a Z4000 to interface with two CW80’s and a MRC Dual transformer.  The Z4000 was out of phase with all the other transformers.  The MRC didn’t have a large blade so I only had to flip the plug.  The CW80’s  do have a wide blade so I’ll have to grind them down.  

Doug