| A | Power plug and ON/OFF switch |
| B | Chassis Earth. It must always be connected to the earth to avoid any possibility of electrocution or equipment damage. |
| C | Fusebox. One fuse for internal power supply protection. Fuse reference is: fuse blade 3A 32V violet Cooper Bussmann # BK/ATC-3 (OPAL-RT Part Number T00-0673) |
| D | DB37F I/O connectors (see OP8662-4/8 Pin Assignments for details). Only the top connector, labeled Ch I0-7/E0-7, is used. |