For you all that have the S12 and use RJ45 modules.. do they get like EXTREMELY hot? Like my 4x modules are reading 185F to 189F which seems even outside of what I would expect them to run temp wise. They are all together in a bunch and I’ll say if I disconnect 1 of the 4 the average temp drops to around 175F so seems I might need to spread them out a bit. Just wondering what you all are seeing?
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I have a couple in mine (mostly DACs otherwise) and they run around 150-160F. I’m not sure if it’s documented, but I do recall it being recommended to use modules that are rated for 2W or less to keep temps down when filling up the switch. I know those modules are generally a bit pricier though.
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RJ45 modules use a lot of power relative to DACs and fiber modules, and some a good deal more than others. They’re expected to run much hotter. I’d double check their data sheets to see their max temperatures, but that’s probably OK. I would space them out like you mentioned to help that a bit.
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Can I ask.. how do you know exactly how much power they consume. I say this because I see alta pulls volts/amps like below but honestly that is very little power draw so I’m unsure how people measure this? I assume the datasheets(that most chinese vendors do not provided lol) or perhaps some sort of device that measures it between the two?
Yeah, I’ve usually seen it listed on a datasheet or wherever the module was purchased from. For instance, these are the modules I’m using Amazon.com: ipolex SFP+ to RJ45 10Gb Module, Support 1G/2.5G/5G/10GBase-T RJ45 SFP+ Module, Compatible for Cisco SFP-10G-T, Ubiquiti UACC-CM-RJ45-MG, Mikrotik, Netgear, TP-Link, D-Link and More, up to 30 Meters : Electronics
They state <2.5W in the description there. The nicer, more expensive ones might state 1.8W max or 1.5W max, like these:
Cisco SFP-10G-T-100 Compatible 10GBASE-T SFP+ Copper 100m RJ-45 Transceiver Module (LOS) - FS.com
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Mine are advertised as less than 2.5w but honestly guess you never really know unless it’s from a known vendor that can be trusted.
Bunk values from DDM (where we read that info) on cheap modules is pretty common. There’s absolutely no way that’s drawing 6 mA and generating that kind of heat, that’s impossible. But that’s the only source of module power consumption, so I don’t think it’s viable to determine how much it’s truly using. Maybe if you put the entire switch on a kill-a-watt or similar meter, let it boot and stabilize power consumption, then plug in the modules one by one and see the usage change. Not perfect, but might be the closest you’ll get when the module doesn’t have accurate reporting.
They apparently claim it has a marvell aqr113c. So guess it’s an aquinta type. Guess I’m going to separate them for now and maybe stick optical sfp between them later as it seems they drop a lot in temp if just one is off so being away from each other will probably mitigate it for now. Guess hope lower power options become cheaper over time.
Also guess I could try what you are saying as well since I have a kilowatt
For anyone reading this thread.. I’ve been researching a lot more. The ones I have are running “Marvell AQR113c” and while they aren’t the hottest(amazingly) they do run very hot apparently. The chip itself is good for 110+C but I question if they will actually last and apparently they can thermal throttle. I am still going to run them separate for a bit but if I ever need to populate the switch more that won’t do.
Amazon.com ← my research shows these will run much cooler. You apparently need to get the 100 meter versions to get the better chipset but some have said the 80 meter actually does have the better chipset as well. The seller does not appear to publish the chipset though. Just stating the “latest marvel” chipset which isn’t helpful to be honest but whatever. They supposedly have Broadcom BCM84891L chipsets in them which is the newest gen for low power. They are about $20 more though then I paid for mine as I paid $25 an SFP for what mine are. I’m debating on buying one to just try it out. They are 1.45W→1.6W depending on distance apparently.
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So bought one of those modules.. It is sitting around 126-127F 52± a few after the decimal. I have two optical SFPs as well one which is the SFP back to the route 10 and one that is handling all my AP traffic. The AP one goes around 115F(46C) and the one back to the router is around 127F as well.
The RJ45 SFP’s that I had previously when stacked together would up to 190F(88C). So far when they are by themselves they are around 152F (67Cish). The optical SFP are occupying ports 11/12 but the RJ’s are seperate at Port 1 and Port 8. I think I’m going to send the other RJ45 ones I bought back(one already is having dropping issues anyways) and then buy 1 more of these cooler ones.
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