To Connect: To Disconnect:
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).
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.
S035 
CAUTION: 
Never remove the cover on a power supply or any part that has this 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.
Attention: Go over 
“Installation Guidelines” on page 137 to ensure that you work safely.
CAUTION: 
•  240 V dc input (input range: 180-300 V dc) is supported in Chinese Mainland ONLY. 
•  Power supply with 240 V dc input cannot support hot-plugging power cord function. Before 
removing the power supply with dc input, please turn off server or disconnect dc power sources at 
the breaker panel or by turning off the power source. Then, remove the power cord.
Procedure
Step 1.  Make preparations for this task. 
a.  If CMA has been installed, do the following: 
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ThinkSystem SR860 V2 Maintenance Manual