SG 300-10 PP not powering PoE as expected

[soupensu]

We have a brand new SG300-10PP

We have a total of 8 PoE devices that need to connect to the SG300-10pp

Each devices consumes ~ 6-7 watts/each

We connected 7 devices and the PoE works and devices work fine

We then connected the #8 device, but it will not power up over PoE ( note all ethernet cables are less than 50 feet and are good)

Tests:

1. If we disconnect any of the other devices #1-7, then the #8 devices starts to get power and operate.

So it appears that there is a power budget issue. However , the SG300 web console indicates we are well below the maximimum allowed of 62W

It indicates that we have 20 watts available.

Any ideas?

[devils_advocate]

Yeah I have seen this issue before.

It was bizzare as the switch claimed we were below the PoE limit but simply refused to power them all, unless we unplugged one.

Ended up having to put in the -MPP switch in which had more power.

Personally it made me distrust the GUI in term of how much power was actually being drawn, although the CLI said the same to be fair.

We didn't have Smartnet on them at the time and was on a limited timetable for the install so ended up banging in the MPP and it works fines.