Hey Tony, thanks for the important battery issue as a safety precaution. :-)
 
I'd like to add some general safety tips:
 
- electricity is dangerious and KILLS. Get a skilled professional to do the wiring and setup or risk frying your equipment
- When designing such, do not load with any device that has capacitiance, inductance loads eg a motor drive
- Use sequential startup to devices as you do not want to create a load surge on the batteries.
- Safety first. Wherever possible, including inputs and outputs add in-line fuses on DC /circuit breakers on AC lines to prevent risk of fire or shock or accidental shortcircuits
- Use correct cabling and terminators. Eg on DC side from batteries to invertor/ups, always use heavy duty flame retardent cables. connectors should be anti-corrosive and covered with Gel to prevent moisture buildup.
- ALL outlets must be clearly marked as BACKUP supply ( DC or AC )
- if you have kids, ensure the entire system is raised a few feet above ground and locked securely.
 
Pls add/correct as needed.