Starlink on Pure DC Power
Welcome to this next edition of Off Grid CTO featuring my projects and experiences working as the Chief Technology Officer of ModelOp, a great software company designing enterprise management of AI and traditional models. It’s been a little whiles, and I will be posting more soon. This edition actually comes to you from in flight on an airplane headed to a customer visit, so things are changing for sure!
In this episode I will be exploring how I have adapted a Starlink terminal to work on DC power, without their provided router, and without cutting up the expensive and hard to get cable they provide you.
I am providing this blog not as instructions, but just to let you know what I did. This could cause your Starlink to blow up, malfunction, and probably void your warranty, so please proceed at your own risk. If you are not good at wiring things and creating connections for ethernet and power, this is probably not the project for you. Again, I suggest you don’t do this…
The ethernet adapter with the connector cut off showing the two sets of wires inside. You want to use the thicker wires, as the thin ones go to the ethernet port on the adapter.
The Ethernet Adapter
I finally after waiting for over a year with a deposit down, received my Starlink unit. I am temporarily back in my Utah home taking care of spring chores, but will be bringing the Starlink up to my off grid cabin this coming weekend and giving it a real trial in the remote mountains. The issue is, when you get this ‘gen 2’ unit, it requires a giant and ugly router to both power the unit and provide wifi connections.
This router is not very capable and has very limited configurability and is not up to my requirements for running a network. Further, it requires 110v connection. This does not fit into my DC first power in my cabin, as every conversion causes a loss. So I was determined to convert to running this unit without AC power. I’ve read several people who have cut the cable and put ethernet on the end of it to allow for this, but the cable is proprietary, hard to come by, and quite expensive. They sell an ethernet adapter that hangs off of their router to allow to ‘bypass’ it, but you still have the AC connection. This was not going to work for me, plus space in my cabin is at a premium.
So I got all the equipment, including the ethernet adapter, and hitched it all up for a try out and sure enough it worked, but was quite large and clunky with all of this stuff required… Then it hit me. The ethernet adapter itself provided me with both ends of that proprietary connection, and was less than half of what a cable costs…. So I decided to open it up and see if I could get the connectors out.
What I discovered when looking at the circuit is it is actually a pass through of the Starlink connection, plus a second set of skinny wires that export an ethernet connection from the router out to the ethernet port. So what I had in my hands was a cheaper way to cut the cord and create the required connections without changing the expensive cable, and make it so I could have a plug in way of creating a DC connection and remove the router entirely.
Cross the cables
So starlink actually utilizes standard ethernet connections and 48v POE, at about 100w maximum. But for some reason, they decided to swap the wires and not utilize a standard wiring scheme. So in order to utilize a standard POE injector, you must swap the blue and green pairs temporarily to get the power on them, then swap them back to get the data going into the right place. this is the reason for having to wire your own connectors. The diagram to the right explains this, which I borrowed from a previous reddit post on the process.
So what I did was to do the first of these swaps right on the Starlink ethernet adapter. I simply cut the proprietary connector off, then crimped on an ethernet connection following the ‘b’ standard but swapping the wires as described. I now had a nice plug from the female side of the Starlink dish, which allows me to use the existing long cable to plug in, and a male side ethernet plug that can go into the POE injector and receive power from a DC power supply. I was now half way there!
I also purchased the recommended POE injector listed on the right. It puts power on all 4 pairs which is crucial to making this work. One that only charges the normal pairs is not going to necessarily work, so this one seemed to fit the bill and was readily available. I also added a standard 200w 12v->48v DC buck converter. There are tons of these out there available, and almost any of them will fit the bill. It has to be at least 100w though so if the heater on the Starlink kicks on, it will not overload it. This connects easily to the POE injector and will supply the power for the Starlink dish.
The swapped wired ready to crimp onto the connector. Notice the swap of the pairs. This is very important!
I then built a short cable that performs the exact same swap on the male end, and a standard 586B connection on the female end.
A Short Patch Cable
Then I needed a short cable that goes from the POE injector to the PC or Router that we will directly connect to the Starlink dish. This I made as male to female cable that swaps the same pairs on the male end to basically put the data back onto the correct lines for a normal connection. This is vital to making it all work.
By doing a simple cable like this it allows me to connect any standard patch cable to this, and be served up a single IP address by the dish itself, without involving their router at all.
Check and Double Check
After you have it all wired up, I would personally suggest checking, double checking, and then not actually going through with this modification. I am sure this voids your warranty, and you can certainly utilize the included router and cables with an inverter to power your dishy, but for me I just couldn’t let it sit that way and want the highest efficiency both space and power wise. So for me I was OK with the risk. Proceed at your own caution.
Make sure the pairs show swapped as shown on the tester
Connected all together…. Ethernet adpater from Starlink goes to the POE side of the injector, patch cable goes to the data side, and to PC or router from there.
Connecting All of the Pieces
So once you have all of these pieces built, then the connection is pretty straight forward. Simple plug the Starlink ethernet adapter you modified into the POE injector. Then plug your patch cable into the other side of the POE injector (non POE side), and then use a normal ethernet patch cable to go either to a PC or router. Then plug dishy into the ethernet adapter. Finally plug your buck converter into a DC power supply. You are now going to have to wait for a few. It takes dishy a bit to come all the way up to respond. So don’t panic, but be aware of a few things.
First, if you are plugging dishy into a router, you are going to need to make a static route to 192.168.100.1 for your wan port. There is a landing page there that gives you access to all of the standard web interface stuff to interact with dishy. That will also allow the ios or android app to work as well.
That said, I suggest you first test with a direct connection to a PC, and in that case you don’t need to do a thing. You will have that route already defined.
Well with great nervousness about blowing up my new dishy, I went ahead and applied power. I had this directly connected to my pc, and sure enough I saw an ethernet link and traffic. Clearly, this was going to work.
After a bit of time, I was issued an IP address, and going to 192.168.100.1 lead to the dishy page. This clearly works. There is no router involved here, and is a direct connection.
I wanted to set this up before I went remote again, so I am roaming, but even then I am seeing just fine speeds. So success and am looking forward to installing this at the off grid cabin this Friday!
Success! Online and with roaming great speeds!
And the Results are In!
And so as you can see I sit around 19W to 48W of power usage of direct DC. Typically, it sits around 35W of usage it seems. In the long run it will be interesting to see what it takes for power over time, but for right now it is in line with what Viasat utilizes.
So now I am ready to go with a pure DC powered Starlink unit and am excited to see the difference it makes at my cabin. Unlimited data and reduced latency is going to be a game changer. The next blog will be on the other half of the config to make it work on my network, and the results I actually see.
So join me next time to see what Starlink really means to an off grid CTO!