CRS310-8G+2S+IN batches are broken

Hardware MikroTik hardware general
1

DISCLAIMER: I could have been VERY unlucky, and/or overzealous about checking my hardware on arrival, so please read this with the disclaimer that I only have had less than 15 of these in my hands. But to my defense, I see others with my problem.

Now, I love Mikrotik switches, and I have never had any issues other than 1 failing out of hundreds, but the CRS310-8G+2S+IN model probably need a recall.
There are two main cooling blocks glued to two chips, and the left-most block is failing (labelled “U1”), it simply falls off and sticks to whatever it lands on. Normally you won’t notice this if the block doesn’t short anything out or the unit gets too hut, which is what alerted me to this issue. The most common scenario, is that it sticks to the chassis.

I had an order of 10 where one suddenly overheated, and I took it apart, it was pretty obvious why it overheated. So I RMA’ed the ones that had the issue and it took months for Mikrotik to acknowledge the fault. I then got another shipment with the exact same issue on 50% of them.
The supplier couldn’t promise me that they wouldn’t send from the same batch and they wouldn’t check them before shipment, so we gave up on them and ordered from another supplier in another country (DE → DK) to hopefully not run into the same batch.
And now the exact same thing happened again, 50% of the order was broken (I only dared order 2, so 1 was broken).
I suspect this could have happened by the units have been exposed to extreme heat while sitting upright i a storage somewhere, and due to heat pattern, one got so hot that the glue gave out, and it fell to the left (I always see them on the left side if they are sticking to something).

So riddle me this, if I need 20 of those switches, how many times will I have to order and RMA the units before I end up with 20 good ones? It’s an interesting math problem that fits well in a public school test

Please Mikrotik, we need you to look into this.

To everyone else, if you are afraid you have this issue, remove the 3 screws from the casing and check if the cooling blocks are in place, I’ll bet you that in 50% of the cases they are rattling around in there, or are stuck to the chassis.

Regards
/Allan

2

If you’re tackling the issue with “order X, check them and RMA Y … and loop until all are fine” approach, then you’ll never end up with all 20 working (as per Achilles paradox).

Another approach would converge much faster: if you determined 50% fail rate, then order 40, keep the 20 good ones and return (for refund) the rest. If actual fail rate is higher (and the initial yield is e.g. 17 good ones), RMA the others … and take those 3 required ones from the next batch (select the good ones obviously) … and return the rest for refund.

The only thing still to do is to find a distributor/reseller who is willing to accept devices and refund you … without too many questions asked. If your distributor is an honest one, then you can even tell them why you’re returning the merchandise (so they won’t re-sell them further if they should actually be RMAd).

3

Coincidentally, recent:
http://forum.mikrotik.com/t/warning-crs310-8g-quality-by-issue-with-heatsink-inside-loose/178531/1

4

I was actually alluding to Achilles Paradox - and you nailed it :slight_smile: I’m impressed.
Regarding your reseller comment, you really hit where it hurts, my normal reseller just went with sending it to Mikrotik and put me in hold.
That didn’t pan out well, and after 2 months of harsh negotiations, Mikrotik yielded and refunded. But who wants to go through that again on a known faulty product. So we tried shopping around, and no one cared or bothered to take this seriously, they just followed protocol.
So what I actually had to do was order 20 and expect half to be broken, and end up with 10. But hey, this isn’t a crappy TP-Link or Inteno router from my local electronic outlet, so I really expected more.
But if you can point me in a direction of a reliable reseller, I’m all ears!

5

I will just update this thread with the fact that it happened again, and we have given up completely on the switch.
We simply can’t get the suppliers to check them first, and we waste weeks sending unit back and forth, it’s a complete circus show.
If anyone knows a supplier (anywhere in the world, I’m that desperate), that will check before shipment, please drop me a name.

6

You are thinking that there can still exist somewhere any professional actually behaving professionally?
It is possible, but it is highly improbable.
Professionalism died circa 2000, maybe a little earlier.

But, to be fair, the circus is actually one of the few cases where members are actually very professional, maybe because in most the things they do they risk their own lives.

Parachuting comes to mind as another of such fields, Maxim Eleven :wink: :

( those that are still with us are pretty much professional)

But distributing routers and switches? :unamused:

7

New CRS310-8G+2S+IN ordered a few days ago, still with the issue (heatsink from the two chips was on one of the Ethernet transformers).
I’ve just opened the case and fixed it myself, should be fine as long as only used in horizontal position and not in a harsh environment.
Temperatures look normal, fan running at low speed (except briefly high speed on power up).
BTW, I see some unused holes on the PCB that could be used to hold a much larger heatsink covering all chips (instead of the two separate small ones), that could probably remove need for the fan.

8

i asked LinITX (UK MikroTik distributor) about this, and they are willing to check stock before sending it if you ask.

(i have no affiliation with LinITX other than buying most of my MikroTik gear from there.)