How do you use PoE? Do you need a splitter, an injector, or both? How does it all work?
Let’s dive in! PoE is one of those things most of us never have to deal with and can seem like a mystery. It’s not. It’s super simple, let me show you how it works.
First, P-O-E stands for Power Over Ethernet. It’s a way to combine BOTH the power AND the Ethernet connection into one cable. You’re literally running power over an ethernet cable.
When deciding to use PoE, check to see if your hotspot supports it natively like the Nebra Outdoor (Option 1, below) or doesn’t (Option 2.)
Here’s a handy Hotspot Connection table to figure out what you have.
Note on the Syncrobits that they have “Passive PoE”, which is non-standard. Make sure you get the right type of Injector for them. Ok, on to the diagram.
Ok, but what do injectors or splitters actually look like? We’ll start with an Injector:
See how the power cord comes in on the right side, and then there are 2 ports on the left?
One of those ports, “Data In”, is for the ethernet cord that comes FROM your router. That brings the data INTO the injector.
The other port, labeled “Power & Data Out”, is what you’ll use to take both power and data OUT, going up to 300′ over an ethernet cable to your hotspot.
What about the Splitter? What do those look like, and when would you need one?
First, look up your hotspot specs. SOME hotspots (the outdoor Nebra, for example) support PoE natively; they don’t need a Splitter on the far end.
However, if your hotspot has a port for a power plug (USB-C, barrel plug, etc) AND an Ethernet port you can use a PoE Splitter. Those look like this:
That blue cable coming in from the bottom represents the long cable run from the Injector to wherever your hotspot is. The Splitter than splits out the Power and the Ethernet, and you connect both to your hotspot.
The one tricky thing is being careful to not “double power” your hotspot. Don’t run PoE AND a power cable to the hotspot. It sounds silly, I know, but I’ve heard stories about the “people who think more is better”, so I figured I’d warn ya.
If you’d like to support the blog, pick up your PoE Injectors & Splitters via these links:
- PoE Injector 802.3af, auto detects power (NOT passive)
- Passive PoE injector (only for a few Hotspots, check your specs)
- PoE splitter option 1 (a box with a DC power port, you’ll need to buy an additional cable)
- PoE splitter option 2 (includes cable for a specific power port, like USB-C or micro USB
If you learn best by watching something, here’s a video. Yeah, the cables are a little messy in the vid. If that part of it confuses you, well shit, you’re probably having trouble tying your shoes and should stay away from putting up badass hotspot placements.
That’s PoE explained. Get after it!
Wait, you want to see what it looks like in an actual enclosure, with a hotspot, and all fancy? Here ya go:
~Nik @ GK
Thanks Nik. I use these injector/splitters on my Bobcats, they work perfectly and a little less bulky: https://www.amazon.ae/gp/product/B08P8Z5PDQ/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
A few more benefits for users to think about when using PoE:
a. by removing power adapters from your outdoor case you’re also reducing the heat a little.
b. by having easier access to the power source (lets say at ground level or at least indoors), it’s much easier to power cycle the unit.
Why my ethernet port from my spectrum wifi router is not going when connected to poe injector (basically all cables are connected correctly). Thank you for the answer.
Hmm, I’m not sure mug. Sorry!
Brilliant write-up. Much appreciated. This makes for a clean and tiddy install. I will pay it forward. Cheers.
Hell yeah, love hearing that. Rock on Cap!
For the Outdoor Nebra – does it matter if the injector you buy is 100mbps or 1000?
Probably not; data rate on the hotspots rarely exceed 300 kpbs.
Since I have a Syncrobit I need to make sure I buy a passive injector? Example: TP-Link PoE Injector | PoE Adapter 24V DC Passive PoE
Thanks!
Hi Darren, Syncrobit says “Support for Passive PoE” on their spec sheet. I’d double check with them just to be sure.
My POE splitter is very hot. I bought a DSLRKIT Active PoE Splitter 48V to 5V 5.2V 2.4A USB TYPE A Female 802.3af for tablets and just used a short USB A Male to USB C cable to go into the Sensecap M1.
Does bobcat run on 802.3at or 802.3af? Does it matter? Don’t want to fry my rig.
Good question Andrew, I’d check with Bobcat to make sure. They don’t say anything about it on their spec sheet.
Thanks for the great post. I have a setup where its much easier to get my Ethernet cable from the bobcat to a wifi extender rather than the router. Do you know of any issues using this setup. Thus far, I haven’t been able to get it online even after trying a port forward.
I’ve heard of other people having the same issues with WiFi extenders. Always best to go straight from the router into your Hotspot via ethernet, even when it’s a lot harder to do. 🙂
Bobcat operates on 2.4Ghz Wi-Fi (802.11.b/g/n)
Source: Joe P#0175 (discord channel)
Joe Petrungaro 7/27/2021
Thanks a lot for your posts Nik \(^_^)/
Instead of a POE Injector splitter can I use a POE switch. I have a POE Switch powering other devices.
Hi Amos, sure, the PoE switch should be able to replace the injector. You’ll still need a splitter on the Hotspot side if it’s not PoE capable.
Hey KING, I was doing an upgrade to my RAK and installed a POE splitter to tidy up a hotspot and now my miner says its RELAYING, didn’t before installing the POE splitter. Any thoughts or give it some time?
Shouldn’t be the splitter that’s the issue. Go through Jason’s relay flow over here, that should get you sorted.