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jordanbigel · 22-01-2023, 20:26

A few months ago I installed a starlink dish (standard dish, RV plan) and I mounted it with a rail mount adapter, but I wanted to be able to remove the dish and stow it below in rough seas, and I wanted to be able to completely remove and stow the cable with it, so I installed a RJ45 through-deck fitting made by Amphenol (RJF-544) which they claim is rated to IP67 (for reference, that means "Temporary immersion in water").

Data sheet:
https://www.digikey.com/htmldatashee...544-series.pdf

Mouser:
https://www.mouser.com/new/amphenol/...et-connectors/

I never considered that I might have to stow it below in the rain, and it rained several times in the last few months, at least one of them a fairly serious downpour, and never any ill effects, even got a great signal in heavy rain for days.

But last week in California was an epic multi-day rain event which appears to have set many records and the fitting leaked and shorted out burning the connector in the fitting itself, and the end of the cable plugged into the fitting (from the Dish), and it fried the POE injector also. (one pair of the RJ-45 is carrying Dish power of appx. 50w at 48vdc.)

Currently I live aboard at a marina temporarily (getting ready to go cruising gain full time in a few months) but I was not aboard during this multi-day cataclysm - I had left my boat at the marina and flew to visit family in another state and I left the system powered on specifically so that I could monitor the batteries remotely (using Victron CerboGX/VRM).

When I returned home I found that the connector had gotten wet and caused the damage described above. I re-crimped the connector on the end of the cable from the dish, and I replaced the through-deck fitting (with the same one for now), and the POE injector, and luckily everything works again -- the dish itself was not harmed.

Now, my plan has always been to remove and stow the dish when at sea if the weather is getting rough, that was the whole point of the through-deck RJ45 fitting. And I know it rained a lot, but if this thing was supposed to be good to IP-67 so I expected it would not leak in this scenario, or basically any scenario where fresh water is falling from the sky.

If I had been here I doubt I would have shut off the power and this still would have happened. So now I have learned, maybe there is no solution except just replace it with the same one and be conservative about when it's time to shut it down and bring it inside when it rains hard (there is a Cap which fits over the fitting when not in use, I supposed that might leak also, but if the power is off, no harm I guess, except it will rust out shortly).

I would really like to find better fitting that is more reliable - and the only thing better than IP-67 is IP-68 (able to withstand continuous immersion in water) but I can't seem to find anything suitable so far.

I'm wondering if someone else has solved this problem already or knows of a fitting which would be better than this one.

Thanks in advance!

HeywoodJ · 22-01-2023, 22:16

The industrial standard for this is to replace the RJ45 with an M12 Ethernet connector. Lots of options for cable and bulkhead fittings. Many M12 are only four-wire because that’s all Ethernet needs, but 8-pin M12 are available for POE applications. They also provide the benefit of much better pin contact for better power transfer.

jordanbigel · 23-01-2023, 07:15

Quote:

Originally Posted by HeywoodJ

The industrial standard for this is to replace the RJ45 with an M12 Ethernet connector. Lots of options for cable and bulkhead fittings. Many M12 are only four-wire because that’s all Ethernet needs, but 8-pin M12 are available for POE applications. They also provide the benefit of much better pin contact for better power transfer.

Interesting, thanks. I've never heard of M12 Ethernet before. I just did some quick reading on it and so far I can see it will take a fair bit of research before I can go in that direction. I was not able to find any appropriate through-deck fitting in a casual google search, they look well suited to mounting on a control panel for a piece of large equipment. I need something which can either handle a "panel" that is 1.5" thick (the fiberglass deck) or, like the Amphenol, screws in from the outside with a flange. Most "panel" fittings have a max thickness of about 1/2" - 3/4" (my boat's decks are thicker than many GRP boats).

Also, the POE specs from one manufacturer I read said it was rated for max 2a@30v (60w) - the Starlink can draw up to 120w or 2.5a@48v, and I am not sure if that is okay, but it is possible that is just the rating for the one connector I read about from one manufacturer because the other thing I read is that there exists no standard for Ethernet using M8/M12 connectors, which doesn't mean it won't work for me, just that there are more question marks to deal with.

Frankly, any 8pin waterproof fitting system would work as long as there exists a field-connectable end which I can crimp/screw on to a Cat5 cable, since I control both ends of the connection, I guess they could be any connector type.

I will continue to research these types of connectors - the key is finding a suitable through-deck fitting.

**Jammer** · 23-01-2023, 07:56

Jordan,

The Amp connector and all the weatherproof RJ45s I've seen is only IP67 while connected. The other thing you have to watch is that the cable diameter must match the connector specification.

The 120w POE devices use more than one pair for power so the current per conductor is less than 2.5 amps. I've worked with higher power POE connections with weatherproof connectors in the lab and have not had problems with the connectors from the current carried. The main thing to watch with higher power PoE is that for longer cable runs you have to use somewhat heavier gauge Cat 5/Cat 6 cable to get the full rated wattage.

**Jammer** · 23-01-2023, 08:01

Quote:

Originally Posted by jordanbigel

Interesting, thanks. I've never heard of M12 Ethernet before. I just did some quick reading on it and so far I can see it will take a fair bit of research before I can go in that direction. I was not able to find any appropriate through-deck fitting in a casual google search, they look well suited to mounting on a control panel for a piece of large equipment. I need something which can either handle a "panel" that is 1.5" thick (the fiberglass deck) or, like the Amphenol, screws in from the outside with a flange. Most "panel" fittings have a max thickness of about 1/2" - 3/4" (my boat's decks are thicker than many GRP boats).

You will have to drill an oversize hole and use a thinner mounting plate of G10 or something.

Quote:

Frankly, any 8pin waterproof fitting system would work as long as there exists a field-connectable end which I can crimp/screw on to a Cat5 cable, since I control both ends of the connection, I guess they could be any connector type.

I will continue to research these types of connectors - the key is finding a suitable through-deck fitting.

That isn't true because Ethernet, especially at higher speeds (100Mpbs/1G/2.5G/10G), depends on the crosstalk and capacitance being controlled within a fairly narrow range.

Look at the X coded M12 connectors. They're one of the few that's compliant. There's a field-attachable version that doesn't require special tools that would work for you. I can't remember who makes it. Digikey probably has it.

We also had very good results with the Harting push-pull RJ45 connectors, outdoors, which are less expensive than M12, at least in quantity. We installed thousands. I don't think they're as good as the M12 but we could never sell M12 connectors to ISPs because they were unfamiliar. The Harting push-pull looks like an RJ45, crimps like an RJ-45, and is sort of compatible with them (you have to use a screwdriver to reach the locking tab to disconnect a non-push-pull connector).

There are waterproof caps available for M12. With push-pull there's just a dust cover, if I recall correctly.

**Jammer** · 23-01-2023, 08:10

Here's a field wireable M12 X coded. It's not the one we used, but it's similar.

https://www.automationdirect.com/adc...-17341-0000000

hjohnson · 23-01-2023, 08:40

Quote:

Originally Posted by HeywoodJ

The industrial standard for this is to replace the RJ45 with an M12 Ethernet connector. Lots of options for cable and bulkhead fittings. Many M12 are only four-wire because that’s all Ethernet needs, but 8-pin M12 are available for POE applications. They also provide the benefit of much better pin contact for better power transfer.

Just FYI… 4 wires is all that’s needed for 100mbps (two pair). If you’re running 1Gbps, which is what StarLink does, you need all four pair regardless as to whether PoE is present or not.

ChristianV · 23-01-2023, 14:42

Quote:

Originally Posted by hjohnson

Just FYI… 4 wires is all that’s needed for 100mbps (two pair). If you’re running 1Gbps, which is what StarLink does, you need all four pair regardless as to whether PoE is present or not.

Interesting! Never notice this.

BugzyCan · 23-01-2023, 16:26

Why not just build a little hat to fit over and keep the water out. Should be simple enough to keep rain off it. Condensation is a separate issue, and that is where you run into problems, especially with salt air. Maybe switch to one set of these? https://www.svb24.com/en/raymarine-r...er-pilots.html

If you get the part number from Bulgin and google search it, you can save a lot of money. https://www.bulgin.com/us/products/r...onnectors.html

jordanbigel · 23-01-2023, 17:43

Quote:

Originally Posted by Jammer

Jordan,

The Amp connector and all the weatherproof RJ45s I've seen is only IP67 while connected. The other thing you have to watch is that the cable diameter must match the connector specification.

The 120w POE devices use more than one pair for power so the current per conductor is less than 2.5 amps. I've worked with higher power POE connections with weatherproof connectors in the lab and have not had problems with the connectors from the current carried. The main thing to watch with higher power PoE is that for longer cable runs you have to use somewhat heavier gauge Cat 5/Cat 6 cable to get the full rated wattage.

Thanks for all the feedback. Luckily my cable runs are very short.

jordanbigel · 23-01-2023, 17:45

Quote:

Originally Posted by BugzyCan

Why not just build a little hat to fit over and keep the water out. Should be simple enough to keep rain off it. Condensation is a separate issue, and that is where you run into problems, especially with salt air. Maybe switch to one set of these? https://www.svb24.com/en/raymarine-r...er-pilots.html

If you get the part number from Bulgin and google search it, you can save a lot of money. https://www.bulgin.com/us/products/r...onnectors.html

That's what the Admiral suggested, a little hat...

WRT the raymarine fitting, its only 6 pins, RJ45 is 8, but I like the idea, if its good enough for an autopilot...

Thanks for the links.

wholybee · 23-01-2023, 18:29

Nuetrik has a line of IP67 RJ45 connectors that have covers for when disconnected. That is what I will be using when I permanently wire my Starlink. I've not used M12, but it looks like a quality option.

shimari · 02-02-2023, 19:32

Here's a discussion on Reddit on waterproof RJ45 connections

https://www.reddit.com/r/Starlink/co...ption_for_ipxx

I'm looking to do something similar this month or next.