Tripp Lite SmartOnline S3MX Owner's Manual page 15

3. Installation and Setup
15) Use one cable 5 to connect #77 and #78 batteries.
16) Install another 4 battery packs to the layer (L1). Be sure to keep terminal sides of all batteries up.
78 78
5
5
Left Side
4
3
2
1
15
77
Right Side