[kaptain]

Joe,

I am a bit confused. When you were talking about the Echo charger issue, you measured distinct differences between your house and chassis batteries. If both banks are tied together at the isolator in your picture, I don’t see how a difference in voltage is possible. I must be missing something.

 
Excellent point! However, the voltages of the house and chassis can only converge to the same reading when both disconnect switches are left closed (ON position), regardless the Xantrex charger is running or not.
I have to keep the chassis battery cut-off switch OFF position while the coach is sitting to prevent battery drain.

The steps of my previous measurements were taken in these steps, but now I see flawed:

1) shore power off, house switch off, house battery at 12.96; 
2) shore power still off, chassis switch OFF, chassis batteries 13.0
3) shore power on, thus Xantrex charger on, house battery rises to 14.15v
4) now turn the chassis power switch on. The chassis battery drops to 12.89 (from 12.96);

At this moment, I should have gone back to re-read the house voltage.



If my drawing is correct, the house-B and chassis-B voltages should be converging now (note: All steps were taken without attempting to crank or run the engine)
I can re-check and see if its house-B voltage is dropping quickly right at step (4)
Theoretically, when both shut-off switches are closed, without loads and parasitic leaks,  the house-B voltage goes down, and chassis-B goes up. 

If I have heavy loads somewhere, both battery voltages want to go down, but with the Xantrex charger running, it may not go down too much.
How low it can go is probably determined by the Xantrex FSW-3012 capacity. Marc Newman replaced at least once the charger, the generator, and the engine starter as well because the starter clearly shows the manufacture date:  2015-09. And Marc has had Newell replace his transfer switch eight times, which may or may not be related.

I don't know when these four (4) thick red wires were all connected to the single stud of the broken SurePower 3002 isolator. 

I believe if both shut-off switches are left at the ON position long enough, the voltage of all batteries will read the same. I remember this was the exact case 3 months ago when I attempted to pick up and drive home the 701 when the shop said repair works had been completed and ready for pickup, both battery groups at 4 volts: http://newellgurus.com/showthread.php?ti...8#pid55288
Since then, I have replaced with good batteries.



I will re-check and provide an update.