Things You Should Know - Xantrex Digital echo-charge Owner's Manual

THINGS YOU SHOULD KNOW

Use only deep-cycle batteries in your house battery bank.
Only similar batteries should be connected together in one bank. Do not
connect old and new batteries together or wet and gel cell batteries
together.
Always use properly sized terminals and cables for your interconnecting
battery cables.
Starter battery and house battery banks should not be mixed in the
same bank.
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