Can a WS-24-400B power 18 WS-Minis with 18 UniFi APs?

[TheHox]

Doing wired/wireless project in an MDU.

Looking to put a WS-24-400B in the IT closet, a WS-MINI in each apartment to supply 4 wired ethernet jacks and power 1 UniFi wireless AP in each unit. 18 total units.
yay or nay?

[sirhc]

The WS-24-400B has (2) 48VH Ports (port 1 and Port 2)

So yes a WS-24-400B could power up to (2) WS-6-MINI using Port 1 or Port 2

A WS-24-400A has (4) 48VH ports (ports 1-4)

[TheHox]

Hmm No easy way to power 18 WS-MINIs?

[lligetfa]

The MINI needs 48VH to power it to the max PoE budget and there are only so many 48VH ports as Chris mentioned. While the PoE budget on each MINI is likely low enough to get by with powering them with the other 2 pair ports, you run the risk of someone exceeding the limit on 2 pair.

The ER-X has 24V passthrough that could power any of the 24V UAPs. The remaining 3 ports don't have PoE capability so there is little chance that the PoE budget could be exceeded.

[TheHox]

I wish that would work, I really need 6 ports.

We have 4 bedrooms that all need wired access.
1 Ethernet for the uplink
1 Ethernet port for the wifi AP
The Mini would work perfectly, would be great to power it via ethernet as well, but we could power it via AC power locally using the barrel connector I suppose.

[sirhc]

You can power a WS-6-MINI with a standard 48V .75A port if you do not use more than .75A total power draw on each mini including the the MINI.

So assume the MINI needs 4 watts for itself and say 10 watts for 1 POE device so less than 15 watts then you're fine

So you could use a WS-24-400A and power (18) WS-6-MINI if you are only going to power 1 POE device from each MINI.

You can not use a WS-24-400B as the WS-24-400B only has 48V as a POE option on ports 1-12

The WS-24-400A can power 48V on all 24 ports just ports 5-24 can only do 48V .75A

But now let's assume you power (18) WS-6-MINI and each mini is powering (1) POE device using 15 watts total including core consumption.

So let's assume 48V 15 watts consumption on 18 ports which is 15 watts x 18 ports = 270 watts and assume the switch is using up to 30 watts itself for the core and fans so you're below the MAX power of its 400 watt power supply.

[lligetfa]

If the tenant doesn't have access to turn on PoE, then there is little risk of exceeding PoE budget and so 2 pair power would be fine.

If the tenant wants to hot up additional ports, force them to use their own brick.

[TheHox]

This is college apartments (high end). The internet is included and will be managed by us, they are to not touch anything. Not saying that some kid wont ever start poking around, but that is the plan.

That should work then.

[sirhc]

Well so long as they can not log into the WS-6-MINI and turn on more POE then you should be fine.

[TheHox]

I actually have a bunch of other non PoE items to connect (security, DVR, jacks in the lounge) so I may get 2 of those WS-24-400A and load balance the PoEs on the two.