IBM PC 300GL User Manual page 9

DANGER:
Electrical current from power, telephone, and communication
cables is hazardous. To avoid shock hazard, connect and
disconnect cables as shown below when installing, moving or
opening the covers of this product or attached devices. The
power cord must be used with a properly grounded outlet.
To Connect
Turn everything OFF.
First, attach all cables to devices.
Attach signal cables to
receptacles.
Attach power cord to outlet.
Turn device ON.
To Disconnect
Turn everything OFF.
First, remove power cord from
outlet.
Remove signal cables from
receptacles.
Remove all cables from devices.