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?
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.
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
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.
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.
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.
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 .