| A | Power plug and ON/OFF switch |
| B | ±15V Power indicator LEDs for both OP5511current/ voltage probes included in the unit |
| C | Fusebox. Fuse reference is: fuse blade 3A 32V violet Cooper Bussmann # BK/ATC-3 |
| D | DB37F I/O connectors (see OP8662 Pin Assignments for details). Only the top connector, labelled Ch I0-7/E0-7, is used. |