I don't understand: Lionel Block Section

It appears that you are talking about the 1 3/8" section.  It has 2 purposes: to be used as a regular track section, or as a way to "cut" the center rail.  That's why there is a jumper wire on the bottom which connects the 2 pieces of center rail.

The jumper stays on if you are just using the section to get 1 3/8" of track.  If you use (2) of these with a length of regular track between them, then you pull the jumpers and the center rail is broken at each end so the section is un-powered.  By using a power terminal section of track between the two cut sections, you are then able to provide power (via switch or whatever) to the center rail of the section of track.  Outside rails are connected thru 1 3/8" sections.

10" from rest of loop------ BS-------10" ------ 10" -------- 10" PTS -------BS ------ 10" to rest of loop

(Hope that makes sense of the BS ... block section)

It sound like you have it right.  Also, you can use any 10" straight to feed power to the cut center rail because they all have a tab to connect a power feed.  The Power Terminal Section just offers a notch for the wire to exit from if you are on floor or carpet.

Hope that clarifies!
Ed

You can also feed power to a curved section.  They have tabs too.

Thanks guys, glad I had it right.

I ordered a Atlas HD toggle switch for O gauge, it has 3 on/off switches.

Oh before I forget, its the larger terminal block section 5"(?)

However, it has two wires on each end for the center rail, do I remove both center rail wires on each end of the block section piece? Or just one wire?

I thought the block section (5") has 3 wires - one for each rail.  I'm not sure what you mean by "2 wires on each end for the center rail".

 the larger terminal block section 5"(?).  However, it has two wires on each end for the center rail

What you typed here makes no sense.

Look at the rails on your piece.  You'll see that the center rail and each of the outer rails have a "cut" in them.

When new, the block section has three jumpers underneath that "jump" each respective cut.  With them all in place the track is electrically identical to any regular 5" track section.

You get to choose which jumper(s) you want to remove.  Different for different applications.  For your "just want to isolate power from part of your layout" requires only that you un-jumper the center-rail.

It would be wise to pull the whole wire (which has push-on connectors on each end).  If you left one end flopping around under the track, you'd probably end up with annoying consequences.

  --Joe

[eta: I didn't refresh my window, so didn't see that Eric had typed, already]

Yep, thanks that's what I ended up doing.

ok so now, I have an isolated spur off the switch, with a terminal block and the powered terminal track.

Next question, was I incorrect in hooking up a 2nd transformer to this isolated spur?

My HD switch from Atlas has not arrived to toggle it on and off so I figured, I would test it with the 2nd transformer.

Once I get the toggle, i guess I can either just hook up 2 more isolated blocks to it as it has 3 toggles and either keep the 2nd transformer, or just install 2 more powered terminal sections of track on each that feed back to the powered main and using the Atlas HD switch to power all 3 sections on/off as needed?

RESOLVED! Had a wire on the terminal block input in the wrong place...I need glasses.