What type of transforme(s) do you operate and for what purpose?

Layout uses two 275 W P/W ZW transformers to drive two layout loops and a 1033 90W transformer for the lighting. This power supply combo can handle anything conventional.

On my home layout (14x39) , there are four power districts for my TIU.  I have:

(1) MRC Pure Power Dual

(2) Lionel Powerhouse 135s

(1) Z500 (aux power for TIU)

(1) CW-80 powering lights and switches

I use a ZW-L for all loops (2 main, all sidings, and all (19) dz2500 switch machines)

Z (250 watt), and  (1) 180 watt brick for all accessories.

My small layout is powered by a single postwar ZW. I don't have any operating accessories set up. Just a few parked statically right now. When I get around to wiring them, I will add a Z.

Each power terminal has (or will have) a postwar Lionel #91 adjustable electromagnetic circuit breaker.
That includes the "B" and "C" terminals (switches and uncoupling/unloading track), and will include the terminals on the "Z".

This is what I've done in the past

I'm in the building stage with plans to use:

5 - PH180/Legacy PM combinations for track power.  PMs there for occasional conventional running.

1 - ZWC with PH135s for accessory power.  Provides multiple voltage connections.

1 - Z1000 brick to power DZ-2500 switch machines.

2 - Z500 bricks for TIUs

We have two loops on our 6x8 layout.  I use a 180 watt Lionel brick for each loop.  I like these units because the trains seem to run better and more smoothly than they do with the postwar ZW.  We also use two Lionel 135 watt bricks for accessory and switch power.  All the bricks have a power master so as to facilitate conventional running on both loops and, for the accessories, fine tuning the power that they receive and that the switch tracks receive.  The tracks also have TVS protection.

While this layout is more modest than others we have had, I find that these modern power sources reduce operating issues and help the layout run flawlessly for hours at a time when the kids are using it.

Lionel PowerHouse 180 for trains (with Legacy)

Cheap Bachmann transformers  for accessories.

On my small DCS equipped 9'x6' layout I have one Z-1000 for track power with two Z-1000s and two Z-750s for lighted buildings/accessories. I find the single Z-1000 easily handles up to four engines (two on each mainline) or three engines and a lighted passenger train. I rarely run over 15 smph and don't use smoke unless I have a guest, which is not very often. 

I have a 7' x 16' layout with two loops.  I use a MTH Z4000 and DCS control.  I also use TMCC used to operate a few Lionel locomotives. 

8 x 8 with one Z-1000 for the trains and a Lionel ZW 275 for accessories. Running DCS and TMCC. Recently added a Schuco Disneyland Monorail set (vintage) that will require an MRC DC transformer. 

PW ZW (PMs attached) and PWC ZW (4- 135 W Bricks) to run trains plus 2 KWs set to various voltages for accessories plus quite a few wall warts for SC-2s, Miller Signs, etc. Here's how this all looks on my layout installed below train level and out of sight from viewing area in train room:

On my 5x9 Lionel Dealer Display layout I use a classic ZW. Two loops run by the A and D handles and lights and accessories run with the B and C dials.

Thinking about incorporating another smaller transformer (maybe one of my LWs) for separating out a few of the accessories (barrel loader and cattle platform) that really require fine tuning the voltage for efficient operation.

JHF,

  The power station pictured below powers the new Train Room, minus one ZW, that runs the Living Room Christmas layout, and is kept with it.  Acquired over many years I have most of the power I need, would still like to add a ZW-L some time in the future.

PCRR/Dave

STANGTRAIN,

Like your power station, nice set up!

Since I run Conventional, My Main Power source is the Z4k- due to the remote option. I also have a Rowi 400+watt unit and an MRC 135 W Pure sine wave transformer for my workbench test track.

3 ZWs power my pre/postwar O Gauge layout.

2 KWs are slated for my pre/postwar O-27 layout.

6 Zs & Vs for the prewar layout.

I have numerous LWs, TWs, 1033s, 1034s Rs, RWs and more that I use for test tracks, Christmas displays or whatever.

I have a RWX, Type B, Type T, AC1803000 and a few more that are curiosities/display items that I do not actively use.

There are more that I have burred away and forgotten about...

For my new layout under construction it will be a Z-4000 to power 2 loops and a yard and a CW-80 for accessories and multiple wall warts as needed.

I'm a run-it-on-the-floor guy. I use z-500s and 1000s for loops, and to power the DCS Explorer . On two loops I use the MTH 40 style controllers because I run subways a lot and without full DCS the only way to get them in auto mode is with buttons. For accessories I use my vintage Lionel's.

Two fixed voltage 180 watt PoHos linked to TPCs as railpower, one for each Power District.  A 12 VDC wall wart as Tortoise switch motor power with VDC Power Pak as backup.  A pair of variable VAC units as lighting/accessory power.

Wall mounted Power Center located underneath for TMCC /Conventional handheld remote operation above:

Current setup

CW40 for inner O27 loop

CW80 for outer FT loop

Lionel 1.8 Amp Accessory transformer for well ... accessories

Woodland Scenics power supply for Just Plug system lights

Moving towards

KW for inner and outer loops

CW40 for accessories (I may eventually use the CW80 for this, but I need to fix the fan which is failing).

Woodland Scenics power supply for Just Plug system lights