Hi guys,

I've hAP ac router. Tried to install several SFP-modules in it. Everything is OK except the SFP modules temperature. All of them are extremely HOT after 30 secs of work.
Is this normal behaviour of router or smth is going wrong?

BR, Dmitry

My experience with SFP and SFP+ modules (different vendors) in non-Mikrotik equipment is that some SFP types run hot and some run cool. In very same router/switch so most likely "SFP environment temperature" (read: SFP cage in router) is almost the same for all SFP modules ... routers are well ventilated so I don't believe that adjacent SFP cage temperatures would be almost 20° apart from each other. Yes, I've seen 20° difference in temperatur of adjacent SFPs in same router.

On a datacenter environment (fixed ambient temperature at 21°C) my Mikrotik S+85DLC03D SFP+ modules run at ~40°C.
The router health monitor shows a temperature of ~36°C.

On an outdoor installation with an OPTIC-SFP-5324S-20-SC SFP module during winter (outside temperature between 0-15°C) it runs at ~43°C.
During summer (20-40°C) it runs at >60°C. (very rough numbers from memory)

So it depends on the module and on the environment it's being used. But in general my experience is that SFP modules get hot.
As long as the temperature is within the specs, it should be ok (of course, the cooler the better).
The OPTIC module I mentioned has been working in that environment for over 5 years without a hitch.

All of them are extremely HOT after 30 secs of work.

Out of curiosity: how does "extremely HOT" translate into degrees Celsius?

extremely hot means about 65-70 C. I can hold it with my fingers less than a one second after pulling it out of Mikrotik.
But the same module in the other non-mikrotik HW works with temp about ~25C

Hi Chaos,

I want to talk to you about ccr cpu load. Please let me contact with you asap.

My HAP AC is in my non-heated garage, it’s 5C outside and the SFP is running at 43C.

My rb3011 is in my basement which is 20C and it’s SFP is running at 31C.

Identical SFP modules

Yes, the HAP AC does something that makes the SFP run hotter. Does it matter? Not in my experience even using cheap FIberstore brand SFP modules. I’ve had mine running for at least 18 months in the garage and it the temps in the garage vary from -21C to 45C.

I own 2 S+RJ10 spf+ modules and CSS326 switch, these spf+ modules are extremely hot. I have to open the css326 case, put a fan directly besides these modules, and install small heat sinkers.

Working temperature of SFP module:
Commercial optical transceiver: 0~70℃
Industrial optical transceiver: -40~85℃
If it works in between the range, that's normal.

Yep, have the same issue.

Seems to be about 70 C. Methodology to measure was quite simple. I used less reflective than SFP module cases screwdriver bit and put it on three SFP+ modules. And when it got hot (in a few minutes), measured temperature with laser thermometer. This methodology is not ideal and real temperature could be even higher.

Here is my workaround solution. Temperature now managed around 50C degrees.

Here is my workaround solution. Temperature now managed around 50C degrees.

Great Idea, gotta URL for those sinks?

Here is the temps for S+RJ10 in CRS210 and CRS328. Does not get that hot in CRS328. Also not too hot in CRS210 if no connection.

Sure, got it on Amazon, here is the link:

https://www.amazon.com/gp/product/B077V ... UTF8&psc=1

What kind of FLIR did you use?

Hey! My SFPONU module from Mirkotik is also super hot when plugged into hAP ac. Not sure if that's a problem or not. Doesn't matter if the cable is connected, it heats up immediately after installation and doesn't cool down. Don't have any suitable thermometer, but subjectively it's > 60 C since I can't hold my hand on it for more than few seconds.

We have the same issue with mikortik SFPONU plugged in to hex poe (RB960PGS) we are around 80° celsius

We have the same issue with mikortik SFPONU plugged in to hex poe (RB960PGS) we are around 80° celsius

Wow. Well I guess it's the same here, really hot!
Do you consider this normal? For how long have you been using the SFPONU in this condition? Were you given any support for the case from Mikrotik or your reseller?

Since yesterday I have hooked up the new RB750iGS the ISP by fiber and so I have installed a SFP module. The temperature readout was 51 degrees Celsius and not extreme hot but hot and summer coming I was thinking of a way to reduce it. On the front there is not much room to attach a heatsink and for that I have look inside.

Then I thought what if I could clamp it on....so I search for a old hair holder and bent the legs to make a good contact and put it on the SFP. It looks nut much but I get a temperature readout of 47 degrees and so having a temperature reduction of 4 degrees.
....removed...
I can surely optimize the contact area and I have thermal glue and I looking now, how I can use the metal section next to the fiber connector to cool even more.

Update:

There is an other reduction in temperature by 3 degrees Celsius. I removed the hair clamp and put two flat heat sinks at the bottom and top. I applied some TIM (thermal paste) on the bottom one and will glue that one to a RJ45 so it will sit snug.

The top heath sink is pushed between the power connector and that one really sits snug at the SFP and needs also some TIM.

I have eventually switched provider to one who uses point to point FTTH and installed a different SFP module into my hAP ac.
Currently the temperature is 59 at the module and 53 system. The unit is standing inside a plastic enclosure so that could reduce by a number of degrees if I put is into a ventilated env.

I made pictures of the new temporary setup with real heat sinks. The top one is pushed between the powerplug and the SFP and the lower one rests on a dummy RF45 and to press the heat sink up there is a washer between them. Because there is not a perfect fit for the lower one I have applied some thermal-paste. In the final version I will glue the heat sinks to the SFP.
The measurements of the heat-sinks are 2,5cmx2,5cm and the thickness is 5mm. To give the power plug more room you can file in the middle some material away.

Update: I have installed a small 5cm fan to blow over the top heat sink and the top of the hEX S and the temp of the SFP is now stable at 39 degrees and that is also the temp from the hEX S and which is 3 degrees lower than before. The moving air is also drawing warm air through the top holes of the hEX S
Update 2: the fan is so efficient that the temperature of the FSP is below the temperature in the box .

Well done, is a good tip to prevent overheating.

Thank you for sharing this
Can I use these images on my website please?

Greatings

You may use the pictures. Don't forget to tell that not to much tension is put on the RJ45 and the power connector. To reduce the tension on the power connector you should use a round file create a space in the ribs of the heatsink. Glueing is also possible but I first want to order also a 10km version that my be a bit cooler than this 20km version.

I have also a small fan blowing over the RB7606iGS which helps also.

I have that VDSL2 SFP that I bought to experiment (not currently in use, waiting for support by MikroTik) and it also runs extremely hot in an RB2011
I guess SFP in equipment that is not fan-cooled and not in a datacenter environment was not really envisioned.
When I later will use the VDSL2 SFP I'll probably add some cooling too.

I have Mikrotik in the utility close to the outside wall so it gets warm and toasty especially these sunny days. The heat generated the optical devices seems more moderate than purely electrical SFP modules. And those sqaure copper heatsinks looks to me to be very efficient but I don't enough extruding SFP to use them.

There are also cages that have heatsinks and that would be inside the router. There are even peltier type of coolers.

When I turn up the fan the external heatsinks will also draw heat from PCB inside. As soon as it is a bit cooler I go to passive cooling only.

I still want to get some spare to experiment with but a spare for an optical is not a bad idea and they cost less than 10 euros a piece. I read that even in cooled surrounding the lifetime can be even less than three years.

I got me a second RB760iGS and modified it differently. I made a heath conducting bridge between the SFP cage and the metal surrounding the network ports.
This was not enough and I put again the heathsink between the power connector and the SFP module.

The temperature stays below 50 degrees Celsius without any fan cooling. This is also archived because the ambient temperature is lower on the moment.

Wow! I was just about to ask the same thing!

I just got my brand new hAP ac & GPON SFP (genuine MikroTik one).

In a room where ambient temp. is 18C my Tik is showing 50C(!!!) internal temp. Router's CPU is idling, there is no traffic or load whatsover. My Tik is now smelling bad, like a burnt electronics.

I can't touch the SFP with a bare hand. It's extremely hot to the touch.

What happens after I configure my Tik and load gets high (I'm planning a CPU-heavy IPsec tunneling)? Is it safe to leave this unattended? Can we please get an official MT statement here?

I have eventually switched provider and have a different fiber technology.
Installed a different module However it's still heating up. My hAP ac is standing inside a wall box with limited air flow.

The system board temperature is *53* degrees, and the module temperature is *59* degrees.
I should also note that I'm residing in Israel with average ambient temperature around *26* degrees.

This setup is running flawlessly for several months now (the hottest time here), current uptime *95d 07:29:46*

The commercial temperature range of sfp modules is between 0 to 70°C. So if the working temperature of your sfp is lower than 70°C, you don't need to worry about it too much.

Hi, i have a problem with Mikrotik S+RJ10. It is working normal for a few hours after that no traffic on between the switches. I use 2 CSS326-24G-2S+ and 2 S+RJ10 cooper sfp modules to bridge the switches. What i saw is that the temperature of the sfp module is > 90 degrees Celsius.

You will have to install a fan!
The product description of the S+RJ10 was changed:
"Any MikroTik device with active cooling that has SFP+ ports can now be used ..."
So, only when the product has a fan. I think the CSS326-24G-2S+ has the fan only as an option, isn't it?

yes, no fans installed. thank you for your sugestion

I also noticed this behavior when mixing certian vendors. Why is that?

Does it feed with to high voltage/current or drive the transciever to fast?

CRS106-1C-5S in an apartment "wiring closet" with slight ventilation, two SFPs. Both report 56 degrees C.

That's not much headroom considering during summertime it can get some 10 degrees warmer.

I wonder would SFPs run colder with individual, unmanaged media converters. I use CRS for switching only and my edge router has free ports so media converters could be used.

CRS106-1C-5S in an apartment "wiring closet" with slight ventilation, two SFPs. Both report 56 degrees C.

That's not much headroom considering during summertime it can get some 10 degrees warmer.

http://www.crunchytricks.com/2017/03/m4 ... rters.html

I wonder would SFPs run colder with individual, unmanaged media converters. I use CRS for switching only and my edge router has free ports so media converters could be used.

Are you still in the same situation.

I wonder would SFPs run colder with individual, unmanaged media converters. I use CRS for switching only and my edge router has free ports so media converters could be used.

Media converter (TP-Link MC220L) I have used for testing has no factory radiators installed. With inserted SFP, it quickly got hot, temperatures around 65°C without any traffic. Additionally, converter introduced couple ms of delay. My experience was not positive.

I've have took apart couple of SFP from different vendors. Simple ones have one small IC and no cooling at all. Others might have some tape transferring heat to the enclosure.
More expansive ones like GPON SFP might contain more components like RAM, GPON chipset and flash. This requires better design.
For example FGS202 used in France for Livebox4 have cooling for laser module and GPON chipset. Notice thick ~3mm metal radiator under white tape.

Just want to share my chassis mod to keep my CRS317 cool and quiet with just a 140mm Noctua fan:
I CNC milled a replacement cover out from a solid plastic block. In room temperature of 30 degree C, the temperatures of 2x S+RJ10 modules (installed side by side) are kept at 75-78 degree C.

Kewl, literally, so the fan sucks air from inside the unit to the outside?
How do you power the fan?

It's strange that some SFP's get extremly hot when plugged in to some host devices. Higher voltage? Clock-frequency? Power-saving incompability?

Some SFP just get very warm, especially GPON, long-reach SM and 10GBase-T transcievers generate a lot of heat by themself regardless of host device.

Kewl, literally, so the fan sucks air from inside the unit to the outside?
How do you power the fan?

There are two fan connectors. I assume the two little fans als suck the air out of the router but a higher sound level.

I ordered some heat sinks (rasperry pi size) that should work on my sfp cages, the kit also comes with flat copper plates (small size).

I dont dare open up the CCR1009 for fear of breaking warranty much less cut out a section of the lid to attach a fan to suck out the heat LOL.
But I do wonder if it has a power supply connector waiting for a fan.
Where does one find the inside schematic or picture of ones MT unit??

Pictures you can find all over the internet.

duck.com or yandex.com and press on the word/button "images" and before you search on the exact product name of you 1009 like: CCR1009-7G-1C-1S+PC

The SFP cages have holes in the top that let hot air out and you should not cover all with heatsinks. Also a heatsink need that the SFP is in contact with the cage. There is a little air-gap between the SFP module and the cage so that is not as effective. You are then only cooling the cage. The cage is heated by the heat radiating from the module and heat transferred back through the PCB.

The best cooling is moving cool air over the components getting hot. If you have a fan-less one then you could think of attaching a fan to the outside drawing air out through the air vents. Example see my active cooling the huge passive plate covering the RB4011 and the link is in my signature.

It is not clear to me how you attached the fan to the RB4011, what size fan it is, or how you are powering it.
Gather it sucks away hot air from the RB?
All to say not sure if its an applicable remedy for the CCR1009 7 series.
The CCR1009 has a huge heat sink in the back so perhaps I should blow air over that?

This seems to be it.............. I gather the heat is coming from the center TILE CPU block and is dissipated through the heat sink via the copper tubing.
It seems like a fan bolted to the top of the unit with some air gap sucking air away from the block through the top of the router would be a good retrofit idea?
Would mean removing the lid, cutting a round hole through and attaching the fan to the lid or on top of that metal block.

Only problem is that as noted before, I doubt there is a fan supply socket on the board??
https://yandex.com/images/search?text=c ... rpt=simage

That one is totally passive cooled. You see even a sticker on top of the SFP cage that may block one of the venting holes. I used a small 12V fan that is powered by byte tapping in on the 12V poser supply for my 4011...he is on diet you see.
I use plugs for putting screws into a wall and this one are small ones and the ends are just pushed into the slots of housing. The fan is very small and very light (20 gramm) so those two plugs pushed in hold it easily.

I have this one and there are different sizes: https://www.blacknoise.com/site/en/prod ... hp?lang=EN

A very small one and also thin and handles 24V: https://www.blacknoise.com/site/en/prod ... 0x10mm.php

Stick on the left side to the front and suck air out or in and you will extra cool the cage of SFP a few centimeters inside. You can also put an extra fan(s) on top of the heatsink at back if that is really getting hot. I think that is not a problem and it a BIG heatsink.

Those copper pipes you see are heat pipes and they are very efficient in transporting heat from one place to an other. So bolting a extra fan on the top is not the first option to think about.

Video comparing a copper rod and a heat pipe and a heat pipe is just awesome. https://www.youtube.com/watch?v=OR8u__Hcb3k

Just want to share my chassis mod to keep my CRS317 cool and quiet with just a 140mm Noctua fan:

CRS317 140MM Fan mod.JPG

I CNC milled a replacement cover out from a solid plastic block. In room temperature of 30 degree C, the temperatures of 2x S+RJ10 modules (installed side by side) are kept at 75-78 degree C.

Nice idea. That would quiet it down a bit. Did you disconnect the two fans in the back, and use the same fan header?

I'm not having any high heat issues with mine, but those two fans at the back are constantly running at ~4,300rpm which is louder than I would like. (my rack is the next room over from my office)

I might wind up trying this.

Have look at these: https://www.blacknoise.com/site/en/prod ... m.php#tab1

The 317 hasfour leads and that is to regulate the rotating speed. The I linked to has only three leads.