Show Power Consumption of X450-G2

[javfe]

Why does the show power detail query show power in watts in just one of the power supplies?

Slot-1 PowerSupply 1 information:
State : Powered On
PartInfo : Internal PSU-1
Revision : 11
Input : 225.00 V AC
Output 1 : 55.05 V, 0.00 A (12V/715W Max)
Airflow Direction : Front to Back

Slot-1 PowerSupply 2 information:
State : Powered On
PartInfo : Internal PSU-2
Revision : 11
Input : 225.00 V AC
Output 1 : 55.12 V, 0.73 A (12V/715W Max)
Power Usage : 52.94 W
Airflow Direction : Front to Back

Slot-1 PowerSupply 3 information:
State : Empty

Slot-1 PowerSupply 4 information:
State : Empty

Slot-2 PowerSupply 1 information:
State : Powered On
PartInfo : Internal PSU-1
Revision : 11
Input : 225.75 V AC
Output 1 : 55.05 V, 0.00 A (12V/715W Max)
Airflow Direction : Front to Back

Slot-2 PowerSupply 2 information:
State : Powered On
PartInfo : Internal PSU-2
Revision : 11
Input : 225.50 V AC
Output 1 : 55.12 V, 0.73 A (12V/715W Max)
Power Usage : 52.94 W
Airflow Direction : Front to Back

Slot-2 PowerSupply 3 information:
State : Empty

Slot-2 PowerSupply 4 information:
State : Empty

Slot-3 PowerSupply 1 information:
State : Powered On
PartInfo : Internal PSU-1
Revision : 11
Input : 225.50 V AC
Output 1 : 55.05 V, 1.19 A (12V/715W Max)
Power Usage : 86.19 W
Airflow Direction : Front to Back

Slot-3 PowerSupply 2 information:
State : Powered On
PartInfo : Internal PSU-2
Revision : 11
Input : 225.75 V AC
Output 1 : 54.98 V, 0.00 A (12V/715W Max)
Airflow Direction : Front to Back

Slot-3 PowerSupply 3 information:
State : Empty

Slot-3 PowerSupply 4 information:
State : Empty

[FredrikB]

I have the same, and can't seem to find a switch with dual PSU and higher than 70 W power usage

PowerSupply 1 information:
State : Powered On
PartInfo : Internal PSU-1 1529A-45760 800592-00-07
Revision : 07
Input : 229.25 V AC
Output 1 : 52.99 V, 0.00 A (12V/715W Max)
Airflow Direction : Front to Back

PowerSupply 2 information:
State : Powered On
PartInfo : Internal PSU-2 1529A-45755 800592-00-07
Revision : 07
Input : 230.00 V AC
Output 1 : 54.91 V, 0.98 A (12V/715W Max)
Power Usage : 70.80 W
Airflow Direction : Front to Back

System Power Usage : 70.80 W

Some systems use one PSU at a time and only if that one fails the other one kicks in. That can be devious if one side is UPS powered and the other one not. You hook up lots of systems on the UPS but only a few actually draws power from those PSUs. Then when the incoming power fails, the UPS is overloaded.

Looking at the numbers above, it seems the PSU with the higher voltage is drawing all the current, which makes sense. Only when the voltage drops in the PSU providing power current is drawn from the other PSU. If they are coupled together internally via simple protection diodes, this would be the expected result.

B.t.w., really odd that the Max says: (12V/715W Max). 12V??? It's not a 12 V PSU...

[Fredrik_Jansson]

Hi,

I came across this post since we observed the same behavior in one of our PoE switches with two 1100W PSUs.

The "Power Usage" output is sometimes missing in one of the PSUs. It vary which one though. Sometimes for PSU1 and sometimes for PSU2.

As I understand it the two PSUs should load balance? But is there a minimal threshold when that starts?

[FredrikB-NN2]

Sorry, no, I don't know how they are used. It seems only one is in actual use and I guess it depends on whichever was powered on first, or of the load is shifted to the lowest numbered PSU that is operational. Perhaps a higher power draw will "activate" both even if it is below max for one PSU. As these are current switches, TAC could problably elaborate on it if you create a case.

[javfe]

Hi @Ronald Dvorak, thanks for you answer. How much power does the PS1 have to consume for the PS2 to come into operation?