Lenovo ThinkServer RD550 Safety, Warranty, And Support Information page 8

Statement 1
DANGER
Electrical current from power, telephone, and communication cables is hazardous.
To avoid a shock hazard:
Do not connect or disconnect any cables or perform installation, maintenance,
or reconfiguration of this product during an electrical storm.
Connect all power cords to a properly wired and grounded electrical outlet.
Connect to properly wired outlets any equipment that will be attached to this
product.
When possible, use one hand only to connect or disconnect signal cables.
Never turn on any equipment when there is evidence of fire, water, or structural
damage.
Disconnect the attached power cords, telecommunications systems, networks,
and modems before you open the device covers, unless instructed otherwise in
the installation and configuration procedures.
Connect and disconnect cables as described in the following table when
installing, moving, or opening covers on this product or attached devices.
To connect:
vi
To disconnect: