WEBVTT 00:00:00.000 --> 00:00:05.000 Hate, tangled messes of cables? Sick of always having to stay close to an outlet? 00:00:05.000 --> 00:00:10.200 Well, there's actually a way to power certain devices without having an outlet anywhere nearby. 00:00:10.200 --> 00:00:15.500 And I'm not talking about a battery. I'm talking about power over Ethernet, or PoE, 00:00:15.500 --> 00:00:19.320 not to be confused with the Raven guy. The basic idea is simple. 00:00:19.320 --> 00:00:22.600 A single Ethernet cord carries both power and data, 00:00:22.600 --> 00:00:26.600 allowing you to say, never more to a separate power cable. 00:00:27.440 --> 00:00:33.480 How's it going, PoE? Oh, PoE? Ah, and you don't even need any special Ethernet cable. 00:00:33.480 --> 00:00:36.720 Most of us use CAT 5E or CAT 6 these days for internet, 00:00:36.720 --> 00:00:42.360 and either one of these will work just fine. But unfortunately, you can't just connect any two gadgets 00:00:42.360 --> 00:00:47.320 with an Ethernet port and expect power delivery. The client device and the router or switch 00:00:47.320 --> 00:00:50.480 you're connecting it to both have to support PoE. 00:00:50.480 --> 00:00:55.640 The good news here, though, is that PoE switches typically don't cost that much more than regular ones. 00:00:55.680 --> 00:00:59.120 But what kinds of things really benefit from having PoE to begin with? 00:00:59.120 --> 00:01:03.560 One big one is wireless access points. You can often get better Wi-Fi performance 00:01:03.560 --> 00:01:08.000 by using a standalone access point, instead of the one built into your off-the-shelf router, 00:01:08.000 --> 00:01:11.480 and many of these access points support power over Ethernet. 00:01:11.480 --> 00:01:15.480 This can be useful at home, but it's especially common in larger commercial 00:01:15.480 --> 00:01:20.440 or high-density environments that need multiple access points across far-flung distances 00:01:20.440 --> 00:01:24.440 where it would be impractical to run both Ethernet and power cables. 00:01:24.440 --> 00:01:29.000 There are also PoE clocks available in both analog and digital. 00:01:29.000 --> 00:01:34.160 A single Ethernet cable both provides power and connects the clock to an internet time server 00:01:34.160 --> 00:01:37.800 so you'll never have to worry about setting the clock or changing the battery. 00:01:37.800 --> 00:01:42.860 And yet more applications include VoIP, where one Ethernet cable going to your desk phone 00:01:42.860 --> 00:01:48.680 gives you voice capabilities and power. Intercoms, smart door locks, and surveillance cameras 00:01:48.680 --> 00:01:53.040 can all also use PoE. Basically anything that needs a constant data connection 00:01:53.040 --> 00:01:56.080 but doesn't have massive power requirements can benefit. 00:01:56.080 --> 00:02:01.260 So you can send data and power on the same cable because the Ethernet protocol moves data 00:02:01.260 --> 00:02:04.640 using something called differential signaling. 00:02:06.000 --> 00:02:09.540 Basically two signals are sent that have the same voltage, 00:02:09.540 --> 00:02:14.600 but one is positive and one is negative. The orientation of the positive and negative signals 00:02:14.600 --> 00:02:20.120 determine if the bit is a one or a zero. Power over Ethernet just applies a larger voltage 00:02:20.120 --> 00:02:24.160 to the wiring inside the Ethernet cable. It doesn't affect the positive negative difference 00:02:24.160 --> 00:02:27.240 of each bit, so data transmission is unimpeded. 00:02:27.240 --> 00:02:31.200 But speaking of larger voltages, just how much power can PoE deliver? 00:02:31.200 --> 00:02:34.960 Well, there are actually a few different versions of the standard that deliver different wattages, 00:02:34.960 --> 00:02:39.400 which we've summarized here on this chart. Those higher wattage versions are useful 00:02:39.400 --> 00:02:44.200 for devices like high powered wireless access points or rotating cameras that need the extra wattage 00:02:44.200 --> 00:02:47.360 to turn a motor. So yeah, all this sounds pretty cool, 00:02:47.360 --> 00:02:53.520 but before you rush out to buy a bunch of PoE enabled stuff like their Pokemon cards, keep this caveat in mind. 00:02:53.520 --> 00:02:56.840 Many PoE devices don't even have a regular power port 00:02:56.840 --> 00:03:02.700 and so can only be powered via PoE. And if you don't have a switch or router with a PoE port, 00:03:02.700 --> 00:03:06.400 you'll need to pick up something called a PoE injector. 00:03:06.400 --> 00:03:09.640 And don't worry, this isn't some kind of weird cyber syringe. 00:03:09.640 --> 00:03:12.800 Rather, it's a little wall wart that plugs into a standard outlet, 00:03:12.800 --> 00:03:16.840 but also features a pair of Ethernet ports. One connects to the client and the other 00:03:16.840 --> 00:03:20.560 to your router or switch. Just make sure the standard supported by the injector 00:03:20.560 --> 00:03:25.320 is at least the same as what your client device needs to ensure it gets adequate power. 00:03:25.320 --> 00:03:28.640 You can even combine an injector with a PoE splitter 00:03:28.640 --> 00:03:31.840 and power a non-PoE client as well. 00:03:31.840 --> 00:03:36.920 Also remember that PoE has a maximum range of 100 meters without a repeater. 00:03:36.920 --> 00:03:40.320 And while that's a fairly long way, you can eat through that fast 00:03:40.320 --> 00:03:46.000 if your cable run has lots of twists and turns. Speaking of twists, that's the end of this episode. 00:03:46.000 --> 00:03:49.520 Ha, I bet you didn't see that coming. Guys, thanks for watching the video. 00:03:49.520 --> 00:03:52.840 Like it if you liked it, dislike it if you disliked it. Check out our other videos. 00:03:52.840 --> 00:03:57.020 Comment below with video suggestions and don't forget to subscribe to TechWiki 00:03:57.020 --> 00:04:00.020 and follow TechWiki. We're making these actually all the time. 00:04:00.020 --> 00:04:06.860 This wasn't the only one we ever made. There's so many other ones and they're coming more.