Dell EMC PowerEdge R740 Installation And Service Manual page 19

Figure 11. AC PSU status indicator
1 AC PSU status indicator/handle
Table 12. AC PSU status indicator codes
Power indicator codes
Green
Blinking amber
Not illuminated
Blinking green
Blinking green and turns off When hot-plugging a PSU, the PSU handle blinks green five times at a rate of 4 Hz and turns off. This
Condition
A valid power source is connected to the PSU and the PSU is operational.
Indicates a problem with the PSU.
Power is not connected to the PSU.
When the firmware of the PSU is being updated, the PSU handle blinks green.
CAUTION: Do not disconnect the power cord or unplug the PSU when updating firmware. If
firmware update is interrupted, the PSUs do not function.
indicates a PSU mismatch with respect to efficiency, feature set, health status, or supported voltage.
CAUTION: If two PSUs are installed, both the PSUs must have the same type of label; for
example, Extended Power Performance (EPP) label. Mixing PSUs from previous generations of
PowerEdge servers is not supported, even if the PSUs have the same power rating. This results
in a PSU mismatch condition or failure to turn the system on.
CAUTION: When correcting a PSU mismatch, replace only the PSU with the blinking indicator.
Swapping the PSU to make a matched pair can result in an error condition and unexpected
system shutdown. To change from a high output configuration to a low output configuration or
vice versa, you must turn off the system.
CAUTION: AC PSUs support both 240 V and 120 V input voltages with the exception of Titanium
PSUs, which support only 240 V. When two identical PSUs receive different input voltages, they
can output different wattages, and trigger a mismatch.
CAUTION: If two PSUs are used, they must be of the same type and have the same maximum
output power.
CAUTION: Combining AC and DC PSUs is not supported and triggers a mismatch.
PowerEdge R740 system overview 19