Lenovo ThinkSystem SR630 Maintenance Manual page 143

S029
DANGER
For -48V dc power supply, electrical current from power cables is hazardous.
To avoid a shock hazard:
• To connect or disconnect -48V dc power cables when you need to remove/replace install
redundancy power supply unit(s).
To Connect:
1. Turn OFF subject dc power source(s) and equipment
(s) that are attached to this product.
2. Install the power supply unit(s) into the system
housing.
3. Attach dc power cord(s) to the product.
• Ensure correct polarity of -48 V dc connections:
RTN is + and -48 V dc is -. Earth ground should be
connected very well.
4. Connect dc power cord(s) to subject power source
(s).
5. Turn ON all the power source(s).
Attention:
• Read "Installation guidelines" on page 83 to ensure that you work safely.
• Prevent exposure to static electricity, which might lead to system halt and loss of data, by keeping static-
sensitive components in their static-protective packages until installation, and handling these devices with
an electrostatic-discharge wrist strap or other grounding system.
A video for this task is available at:
• YouTube:
https://www.youtube.com/playlist?list=PLYV5R7hVcs-Cmxb8e4L4PvMQ7J5PxvuOK
• Youku:
https://list.youku.com/albumlist/show/id_59643656
Procedure
To Disconnect:
1. Disconnect or turn off the subject dc power source(s)
(at the breaker panel) before removing the power
supply unit(s).
2. Remove the subject dc cord(s) and make sure the
wire terminal of power cord(s) is insulated.
3. Unplug the subject power supply unit(s) from the
system housing.
.
Chapter 4 Hardware replacement procedures
133