Starlink Mini installation, cracking the 12 Vdc barrier . . . or not!

Snackchaser · Sunday at 04:30 AM

After lugging around my old heavy Gen-1 Starlink for a few years, I was thrilled to get the new Starlink Mini. It’s small and light, and the router is built into the dishy. It speed tested at 202 Mbps, a very respectable speed, although not as fast as the Gen-3 which typically runs over 300 Mbps. The Mini comes with a 50’ x ~1/8” diameter power cord that has 5.5 mm barrel connectors on each end. It also comes with a 120 volt AC wall transformer that puts out 30 volts dc (vdc.) The Mini is rated to run on 12 to 48 volts vdc, and 25 to 40 watts. It peaks at 60 watts with snow melt on.

The 12 Vdc rating is an attractive feature, particularly for Boondockers who don’t have inverters. However, when I first hooked it up to the Oliver’s 12 Vdc battery… it would’t work?? After some investigation, it turns out that it’s not so simple and I’ll try to explain why:

Given that the AC transformer puts out 30 volts, and the power is about 40 watts, then it would be drawing 1.3 amps per Ohms law (40w/30v = 1.3 amps.) With the same calculation at 12 volts, the amperage increases to 3.3 amps. The resistance of the long thin power cord can’t handle this higher amperage and the resulting voltage drop puts it below the minimum 12 volts operating range. In fact, I did some bench testing and found it would only work at voltages over 18 volts.

There are solutions to this issue including cutting the cable shorter, using a larger gauge cable, or increasing the voltage. Without a better option, I chose to increase the voltage. I looked at cheapie power converters that would probably work, but I wanted something more robust and higher quality. I found a Victron Orion TR 12/24-5, isolated, DC to DC Converter, and it was perfect for the job. It has a 12 Vdc (+/-) input and an adjustable output of 20 to 30 Vdc at 5 amps. Standby power is under 80 mA, and it has remote on/off switching capability. It comes factory set at 24 Vdc, but I adjusted it to 30 Vdc output with the potentiometer on the front.

To connect the Mini to the trailer’s 12 Vdc power system, I installed a 5.5 mm female panel mount socket into the Satellite TV inlet. I removed the Coax connector and the 5.5 mm socket and nut fits perfectly in it’s place. Oliver conveniently labeled it “Satellite.” If you need the satellite TV, then install a third “Furrion” inlet as I did for my old starlink RJ45 connector. I mounted the Victron under the rear seat on the street side. The socket wiring was sheathed and routed along the ceiling of the outside storage garage. There are a number of options to pick-up 12 volts in that area, I took power off one of the circuit breakers. I ran the negative wire to the ground bus under the rear dinette seat.

The Mini comes with both a snap-in kick-stand and a 2” pole mount, and they’re both necessary for optimum RV use. I prefer having it on a pole, but we often have to move the dishy away from the trailer for a clear sky view. That’s why it’s a bad idea to shorten the cord. It also has an RJ45 port that I suppose is for hardwiring without WIFI, but I probably won’t ever use that feature. I built-up some PVC fittings on my 10’ Electrical Metallic Tubing (EMT) mast to fit the Mini’s pole adapter. (See the post for Tacky Starlink Dishy Mast). A little sanding was involved, and the starlink mount uses a thumb screw to hold it in place.

It’s better to turn the Victron off when not in use, so I recommend using the remote switching feature with a switch installed in an easily accessible location. I’m too forgetful to switch the Victron off every time, so I came up with a way to turn it on & off when the Mini’s power cord is plugged in & out. Read on if your interested in that part of the installation:

The “three pin” 5.5 mm female socket sold by Amazon has a built-in switch that’s designed for appliances that use either batteries or a 120v transformer supply. When the transformer is plugged in, the pin-3 switch opens to disconnect the batteries. This is opposite of what’s needed for the Victron remote switch, but it can be used to trigger a digital relay and it’s actually easier than it sounds.

Amazon carries fun little programable 5 &10 amp timer/relays for under $20. I already had the 10 amp version in the Oliver for a hot water recirculation pump timer, and it works great! The 5 amp is adequate for this application, and you will also need the $20 dollar re-usable Bluetooth programer. They use 50 μA of idle current, which is nothing, and they can be programed for delay-on, delay-off, flashers, dimmers, duck decoys, and more. But for our application, we’re just interested in the trigger functions, specifically the “ground-open” trigger.

Before installation, the relay has to be programed from a smart phone or computer. It’ links by WiFi to flash the program into the relays memory. Use wire nuts to connect the timer and programer together, and power them from a USB port. Follow the well written and simple programing instructions using the settings shown in the screenshot below.

The relay requires a timing function, so I arbitrarily used function #12, which is “delay-on.” I set it randomly to 1.5 seconds. The trigger is programed to use the “Trig Blue” set at #5, which corresponds to the blue wire used as a “grounded trigger.” The green wire trigger is disabled. My wiring sketch shows that the timer is powered with 12 volts from the Victron’s positive and negative inputs. The relay’s yellow output wire feeds the positive side of the Victron’s remote switch (the negative side is not connected). The Victron’s output feeds the 5.5 mm power socket, and the blue trigger wire goes to the 5.5mm socket’s pin-3. Use a continuity tester to identify pin-3, it’s normally shorted to the negative lead of the socket and it “opens” when the male connecter is plugged in. The socket barrel is negative, or ground, and the center pin is positive 12 vdc.

There is one other step to make this work. This Victron model is “Isolated,” meaning that the input and output “negative” terminals are isolated from each other. It needs to be “non-isolated” because the timer is grounded to the Victron input, and the socket is grounded to the output, and the trigger needs continuity between the two. So remove the jumper wire that comes on the Victron’s remote switch, and use it to jump across the two negative terminals. Victron support confirmed that shorting the grounds is not a problem, it just un-isolates it.

This works satisfyingly well! I checked out the power draw with the solar turned off, and while streaming a video. It was 2 amps, 27 watts (after subtracting the parasite load). That’s a huge improvement over my previous Starlink, and I don’t have to worry about running the inverter and draining down the batteries anymore.

I hope someone finds this useful

Cheers! Geoff