The following illustration shows the LEDs of the power supply. 
Figure 2. LEDs of power supply
LED Description
1  Power input LED •  Green: The power supply is connected to the ac power source.
•  Off: The power supply is disconnected from the ac power source or a power problem 
occurs.
2  Power output LED •  Green: The server is on and the power supply is working normally.
•  Blinking green: The power supply is in the zero-output mode (standby). When the 
server power load is low, one of the installed power supplies enters the standby state 
while the other one delivers the entire load. When the power load increases, the 
standby power supply will switch to the active state to provide sufficient power to the 
server.
To disable the zero-output mode, start the Setup utility, go to System Settings ➙ 
Power ➙ Zero Output, and select Disable. If you disable the zero-output mode, both 
power supplies will be in the active state.
•  Off: The server is turned off, or the power supply is not working properly. If the server is 
turned on but the power output LED is off, replace the power supply.
3  Power supply error LED •  Yellow: The power supply has failed. To resolve the issue, replace the power supply.
•  Off: The power supply is working normally.
Hot-swap power supply replacement
Use this information to remove and install a hot-swap power supply.
Remove a hot-swap power supply
Use this information to remove a hot-swap power supply.
“Read the  
installation Guidelines” in 
Chapter 3 of ThinkSystem 
SR650/SR630/SR550 
Maintenance Manual.
“ATTENTION:  
Static Sensitive Device  
Ground package before opening” 
on Chapter 3 of ThinkSystem 
SR650/SR630/SR550 
Maintenance Manual.
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