12V Ethernet Switch reccs?

Currently have a 5v Ethernet switch, would love to get a 12v one so we can eliminate the need for a VRM, any recommendations? Would love something that has POE

We bought a few of these Brainboxes SW-005 industrial switches. They are only 10/100, but that is plenty for most anything you would need for FRC. They have screw terminals for the power instead of a fragile barrel connector. They are not PoE, but you wouldn’t be able to use standard 48V PoE on the robot anyway. The 12V or 18V passive PoE that the Limelight or radio uses is not really a standard PoE format that you would find on a generic switch.

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This will be the first year for us adding the limelight into our mix and I’m concerned about not having the extra ethernet port for tethered operation at the events. Ideally, we would just add a switch like you guys are doing. How are you powering the switch (and limelight) in your setup?

I would assume that the limelight gets its own breaker slot on the pdp, but do you plug the switch directly into the pdp as well or do you run it off the vrm?

That will depend on the voltage tolerance of the switch. Likely, you’ll want to run it off the VRM since most consumer switches are designed for a constant clean power supply.

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The switch I posted can accept 5-30V, so it just goes into a PDP/PDH slot like the Limelight.

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You don’t need a switch to have USB tethering at events:

We also use the Brainboxes switch and it works great for us!

You plug one of these into the PDP and then your 5v gear into it.

https://www.amazon.com/DZS-Elec-Adjustable-Automatic-Regulated/dp/B07BPY315D/ref=sr_1_43?keywords=buck%2Bboost%2Bconverter&qid=1643987809&sr=8-43&th=1

Please review R203 and be aware that 12 volts on the robot does vary during your match.

I am not sure what R203 is in play here. If we use one of these that provides a stable 5v from a range of 14v to 11v?

I was thinking would “i. circuitry used to create voltages in excess of 24 Volts” come into play on your choice of device?

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i guess its how pedantic you want to get about the word “used”. This will be used to make 5v.

I believe the intent rule is to prevent dangerous voltages being used. Sort of silly how the rule is though, since active POE is 48v but so low a current that its not harmful.

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Or just use a VRM?

for a switch… maybe but if you want to power a pi4 or a jetson nano there isnt enough amps

I believe as long as you show it is making <24v in the configuration you have it on the robot it’s is acceptable.

Also you could make use of the standard CTRE VRM to get your 5v as well right? With ports of other devices if needed.

Maybe stick with a regular buck converter. Just had better luck with these providing a stable output.

It’s strange, but I think it’s within the rules to power the Pi from a cots usb-c battery pack as long as you use cots cables.

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Our team is also going to use these (Brainboxes SW-005) this year. Our mentor attached one to our summer/fall swerve project and I just had the team buy two more.

Thanks for all the input in this thread. I’m likely going to pick one of these switches up as well. I read through the manual a bit more and understand how custom circuits are listed and see that we can chain multiple items onto a pdp breaker as long as it’s only a single wire going to the pdp, so I’ll probably plan to get some type of breakout so I can plug our sensors into the same breaker.

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In past years we powered a 12V netgear 5 port switch from the VRM. However the only netgear 5 port switches I can find online now are all 5V. You could power those from the VRM as well. If you are going without a VRM, as our team is this year (thank you REV!) you can use something like this voltage regulator https://www.amazon.com/dp/B07ZQB6S3L (@signalfade posted a similar product link) You’ll have to cut off the usb adapter and replace it with the appropriate barrel connector. This is the route we’re going this year.

We’ll probably use Brainboxes for next year. Didn’t know about those!

I don’t suppose anyone here with one of these at their shops could let me know what the bolt pattern/spacing is for one of the Brainboxes SW-005? The datasheet shows the holes being 30mm apart vertically, but not what hole size is used or what the horizontal spacing is. Was hoping to have the mounting holes pre-laid out in CAD and cut with everything else while out at our sponsors shop. Not the end of the world if we need to drill ourselves though.