Lenovo x3550 M4 Installation And Service Manual page 279

CAUTION:
The power control button on the device and the power switch on the power
supply do not turn off the electrical current supplied to the device. The device
also might have more than one power cord. To remove all electrical current from
the device, ensure that all power cords are disconnected from the power source.
Statement 8
CAUTION:
Never remove the cover on a power supply or any part that has the following
label attached.
Hazardous voltage, current, and energy levels are present inside any component
that has this label attached. There are no serviceable parts inside these
components. If you suspect a problem with one of these parts, contact a service
technician.
To remove a hot-swap ac power supply, complete the following steps:
Procedure
1. Read the safety information that begins on "Safety" on page vii and
"Installation guidelines" on page 33.
2. If only one power supply is installed, turn off the server and peripheral devices
and disconnect all power cords.
3. If the server is in a rack, at the back of the server, pull back the cable
management arm to gain access to the rear of the server and the power supply.
4. Press and hold the release tab to the left. Grasp the handle and pull the power
supply out of the server.
Chapter 6. Removing and replacing components
261