Assistance Please - Block A to Block B Discontinuance

My best guess is that you have the second transformer wired backwards of the first.  Looking at the measurements you've listed it appears the transformers are set to different voltages, but that shouldn't matter in the grand scheme.   Assuming that both transformers are set to the same voltage, measure between points 5 and 7, and between points 6 and 8.  These should both read 0 volts.  If either measurement reads 10 volts (or whatever voltage the transformer is set to) you have the wires hooked up backwards to one transformer.  

Also, you don't need to isolate both tracks.  you can make one rail connected throughout and only break the other rail to form blocks.  

JGL

Check the transformers first - (along John's point) with a meter -    meter + on transformer red,  meter - on transformer black. If the output is reversed by internal wiring or direction switch is positioned opposite - one should read minus -DC volts or the analog pointer moves toward 0 that transformer's output is not the same as the other. make them the same. Simple as moving the direction switch. mark then to forward when both get DC + readings.

Then, head to the track...

You might want to recheck your wiring to the frog.

John

Also what is the voltage between 7 and 6?

Gentlemen:

Thank you for your good comments.

JGL:

My throttles are set to different voltages only to be able to distinguish between the two throttles at Block A and Block B.  I understand that both will need to be the same for a smooth transition from A to B.   The engine goes straight thru the switch fine.  When exiting the switch into block B, it stalls at low voltages but drives thru at higher speeds.  So all my polarity is good.  The Frog is good.  The engine at low speed will stall at the double gap with the front truck in Block B and the rear truck still in Block A.

I isolate both rails because I am not using common ground.  I intend to trigger signals off the track voltages since all my Tortoise contacts are used to gain a potential of 8 amps instead of 4 amps in the event of a derailment.  I have fused my throttle outputs to 8 amps as well.  I have lots of wire of course, all #12 with many smaller gauge feeders about every 4 feet.

Setting both blocks to 10V, I still get lower voltages at 5/8 and 6/7 around 2V.

Please see my schematic below:  Are you asking me to change the polarity of the 120/17V transformer at point A or Point B?

Moonman:

My polarity is all correct to the best of my knowledge.  I can drive the engine straight thru the switch and also into and onto Block B at high speed.  The Frog is the correct polarity as well.

John:

I believe the Frog is not the problem.  All my Top Rails are (+) and all my bottom rails are (-) .  With Block A set to 10 Volts and Block B set to 14 Volts, here are the voltages as you had asked:

5 - 8 = 3.23 Plus Volts

6 -7 = 3.92 Plus Volts

I am measuring with a Fluke Multimeter with the Black Lead on the top most rail and the Red lead on the bottom most rail.  Frog to bottom Block B rail is Positive 10 Volts.

Here is my  panel and the bottom most switch is the culprit.  I have since added LED lights that are not yet shown here.

Thank you all for your continued interest.