OHAUS i-DT61XWE Manual De Instrucciones página 5

4.
Install the RS232/485/USB board. Secure it with 4 screws.
5. Connect the cable to the main board connector.
6. Remove the following circled M16 cover (for RS232/RS485 application), or
M25 cover (for USB application).
M25
M16
EN-3