Using a POE Switch like an injector?

Fatpizza · 5 Jun 2019 at 02:28

My internet is currently provided by wireless point to point with a small dish installed on my roof, which is powered by a POE injector and the data cable runs straight to the WAN port on my Asus router.
I'm planning on buying a switch(one that supports 10GBe for my NAS, 5GB for my PC etc.), and I thought that I may as well get a POE switch to negate the need for a separate injector.
However after thinking about it for a minute I'm actually a little unsure of how of how I'd use the switch to power the dish whilst also passing the data through to the WAN port on my router.

The setup I'm thinking of, is configuring a VLAN on the switch containing 2 ports, one going to the dish and another going to the WAN port on the router. If I setup both as access ports will that just pass through traffic, having the switch effectively act as a POE injector? Or will this setup not work?

Avalon · 5 Jun 2019 at 03:21

Given the average cost/port on a 10Gb switch, are you sure you even want to think about this? You’ll effectively waste two ports just to save using one PoE injector.

Fatpizza · 5 Jun 2019 at 03:28

Avalon said:
Given the average cost/port on a 10Gb switch, are you sure you even want to think about this? You’ll effectively waste two ports just to save using one PoE injector.

I'm going to buy a switch either way, I understand the cost compared to functionality etc. The only question is whether I spend a little bit more on a POE variant of the switch to clean things up a little.
Either way, I'd like to know if this setup would work? Even just to satisfy my own curiosity.

skyripper · 5 Jun 2019 at 08:24

You'd be connecting a 10GBe port to the dish, you'd need to connect the WAN port also to a 10GBe port. You then need to VLAN those two ports to separate them from your actual LAN.
So thats 2 ports gone already. How much is a POE injector?

Fatpizza · 5 Jun 2019 at 08:44

skyripper said:
You'd be connecting a 10GBe port to the dish, you'd need to connect the WAN port also to a 10GBe port. You then need to VLAN those two ports to separate them from your actual LAN.
So thats 2 ports gone already. How much is a POE injector?

My Internet is "only" ~160Mbps so I'll just be using the standard 1Gb ports for that. The 10Gb port will be going to my NAS (in which I've installed a 10Gb PCIE card), whilst my PC has a 5Gb port coming off the motherboard.
Either way this is irrelevant, I just want to know if my suggestion will work?

skyripper · 5 Jun 2019 at 08:48

If your router, dish will support a VLAN, and your switch is VLAN capable, don't see why not.

Fatpizza · 5 Jun 2019 at 09:12

skyripper said:
If your router, dish will support a VLAN, and your switch is VLAN capable, don't see why not.

Thanks.

bledd · 5 Jun 2019 at 09:19

You need to make sure it's the same type of PoE.

You get 24v and 48v (and others).

What brand is your WiFi dish?

The injector brick that you have should say what voltage etc.

Fatpizza · 5 Jun 2019 at 10:05

bledd said:
You need to make sure it's the same type of PoE.

You get 24v and 48v (and others).

What brand is your WiFi dish?

The injector brick that you have should say what voltage etc.

The injector they supplied with the dish is a 24V 12W adapter.

MassiveJim · 5 Jun 2019 at 10:19

do you have anything else that is POE ?
I would have to have at least 3 POE devices personally before I considered a switch worthwhile

bremen1874 · 5 Jun 2019 at 10:38

Fatpizza said:
The injector they supplied with the dish is a 24V 12W adapter.

That’s not going to work with a standard PoE switch unless the dish itself is more flexible about its power.

bledd · 5 Jun 2019 at 12:36

Fatpizza said:
The injector they supplied with the dish is a 24V 12W adapter.[/QUOT

A standard Poe switch will be 48v only. So it will either fry your dish or just not work. (Usually a device will auto sense that it's too much voltage and not run any to the device, but you can't be sure unless you know what the define is)

What brand is it? If it's a ubiquiti injector then you may have options, personally I'd leave in the supplied injector.