Help diagnose a mysterious but substantial voltage drop!

[Ampster]

Having screwed up in every way I could find, I've done things like get shunts in backwards, connections on backwards, display wired on the wrong side of switches, etc.

Does No One diagram their systems?

Sometimes but after seeing the diagram that @FilterGuy put up I am wondering if there is a simple drawing program that can do one line diagrams like that? I would also like to play around with some battery connection ideas like in the Wiki.

 

[Ampster]

I'd like to offer an update to this mysterious problem. .....

Thanks for the feedback on the mysterious problem. In reviewing the thread I would guess that the slow decline of the voltage was the caps in the inverter discharging after the faulty BMS cut off the current from the battery.

 

[Dzl]

Sometimes but after seeing the diagram that @FilterGuy put up I am wondering if there is a simple drawing program that can do one line diagrams like that?

checkout draw.io

Can be used for simple diagrams like this:

Or more complicated diagrams like this (the icons/graphics are imported not drawn in the program):

 

[FilterGuy]

Sometimes but after seeing the diagram that @FilterGuy put up I am wondering if there is a simple drawing program that can do one line diagrams like that? I would also like to play around with some battery connection ideas like in the Wiki.

I use PowerPoint, As @Dzl mentioned about draw.io, If I need images I import them into PowerPoint. (Here is a tip: On windows you can cut-n-past from powerpoint directly into a forum post.)

If you don't have Powerpoint, Google Slides is essentially the same program.... but the direct cut-n-paste does not work.

I sometimes use tinycad to draw circuits: https://sourceforge.net/projects/tinycad/

Here is another tip for putting images into a forum post: Get the image you want on your screen and then use the snipping tool to make a copy. You can then past directly into a forum post. (The snipping tool ships with windows) You can also use the snipping tool to cut-n-past an image into PowerPoint.