M;
There's no way we can help you without knowing,what kind of Alternator you have.
Look it up in a Motors Manual at your local Library.
The way mentioned (series) by Walt, Bill & Joe is how your 48 is wired for a Generator. This is okay if your wiring is good.
The drawing you submitted is WRONG. Don't put power to anything, yet.
J;
There's more than one way to measure current flow.
