MikroTik

One of my RB450 went down yesterday evening because of two on-board capacitors which exploded (6.3V 660 uF) - hope that I was able to read values correctly, their cases ware to damaged. It look like a very cheep bad quality parts. I thing that RBs deserve more reliable parts. Luckily I have soldering station by the hand and two Caps (6.3V 1000uF), so I was able to replace them and RB works fine again. Otherwise network down time could be much more longer, because there was no spare router.

This was already explained in the past, that there was a small number of defective capacitors in RB450, we quickly changed the supplier and there are no more problems in new products. If you have one of the defective models, please return the device to RMA or replace the caps if that is easier for you.

Oh, such a quick response. Good to know. But now I have two brand new RB450 on my desk. I have bought them this morning, hour ago. I it seems that vendor of caps is also Su'scon, same as in the broken caps case.

This was already explained in the past, that there was a small number of defective capacitors in RB450, we quickly changed the supplier and there are no more problems in new products. If you have one of the defective models, please return the device to RMA or replace the caps if that is easier for you.

Sir, I beg to differ. Last week one of mine RB750Gs went down with a bad case of leaked capacitor . I would gladly pay one or two euros more for high quality caps rather than suffer unpleasant downtime and pissed-off customers.

the manufacturer is the same, but the supplier is different. the problematic caps had fake caps mixed in with the authentic ones. new shipments are all good ones.

This was already explained in the past, that there was a small number of defective capacitors in RB450, we quickly changed the supplier and there are no more problems in new products. If you have one of the defective models, please return the device to RMA or replace the caps if that is easier for you.

Sir, I beg to differ. Last week one of mine RB750Gs went down with a bad case of leaked capacitor . I would gladly pay one or two euros more for high quality caps rather than suffer unpleasant downtime and pissed-off customers.

this could happen also because of other reasons. send the RB750G to RMA. also, RB750G is already discontinued, ie. it's an old product. Maybe it was made during the same time as the original posters RB450

My RB450G was bought in 05.2009. RMA Guarantee has passed, luckily replacing of caps fix it

Oh, such a quick response. Good to know. But now I have two brand new RB450 on my desk. I have bought them this morning, hour ago. I it seems that vendor of caps is also Su'scon, same as in the broken caps case.

also the Suscon model should be different, is the lettering not different on the old and new ones?

My broken caps ware green. I'll try to read lettering in the evening. Hope it is still readable.

So far, in the past 2 months, I've had a dozen 450gs, 3 433ahs, and 2 411ars die by this.

I could care less about the 5 minutes of soldering or the 60 cents for replacement caps, it's the drive time and customer dissatisfaction.

Solid routers. As long as the caps hold out. Would be at less than 1% failure rate over 2 years. But I'm over 5% at this point.

Go figure. Almost every one of them went out 2-3 months out of warranty.

I had a different thread going about my dozen or more 411ah's that have failed. They all have the green capacitors that now have the tops swollen. (6.3V 660 uF. I noticed the new boards have black capacitors that are 680uf, and have one less. (the one on the side opposite the pair)

Can someone give me a suitable part number so I can get some and replace. I haven't located the exact ones and I'm not sure which numbers are critical, i.e. 6.3v, etc.

Thanks

I just had 2 complete lockups on my RB750G. Maybe the same issue. I'll likely see it soon.

I have 5 RB 411AH routerboards all died within a few weeks of each other. Same deal swollen caps. All five boards were purchased a liitle over a year ago and put into service at the same time. Now I have to pay a tower climber to replace boards that should not be failing. Also I thought the cap problem in the 450 was some time ago, seems like if these are just now failing after being produced 1 year ago that who knows what boards can be trusted and which ones cannot. Will I have the same problem with the new boards I purchased last week to replace them a year from now???

Hate to have to post here, but the cap issue is far greater then they are letting on..
On my desk, I have over 20 411's 2 411ah's, and my techs have at least another 4-5 each
in their trucks..

This is costing me a fortune in board swaps, and truck rolls..
And I know we have already thrown away a bunch of them.. Now we are having to
spend $$ to get the caps replaced, and cross our fingers they run after that.

R

A little more clarification. The old device batches had Suscon SJ series capacitors, the new ones have Suscon MG capacitors, with more guaranteed lifetime and higher quality as well. If you will replace them, use the MG series.

Us too are having more problems with capacitors. First, we had problems only with RB450/G series, and now we have problems with 411, 433, 750/G etc etc...
We also have noticed we have more and more malfunctional routerboards.
It is not a problem replacing a bad capacitor, but the problem is the downtime for our clients.

We are also having problems with 411 boards. 4 failed in the last 2 weeks. 3 bulging Suscon SJ Capacitors on the board when it happens. Green in color with Gold markings. Arrgh, I just installed 45 of these boards... all require bucket truck rolls.

I've been replacing the caps during spare time in evenings. some of the boards had been in use for a long time. Can't help but to believe that it is temp related, as we've had a month of 100+ degree days, which we didn't have last summer.

Hi,

We seem to be also having problems with RB750 units that seem to have ceramic type capacitors.
Can these also be the problem with routers locking up - the symptoms are identical to the RB750 with the Suscon SJ parts? If so, can these be replaced as to RMA these is not worth it for us and does not give a good impression to our end users, especially since we still have the backup/restore issue to new hardware.

Rgds,
Mark.

I have not seen this issues on any of our 750g/l and 450g. Is there a guide on how to replace them somewhere ? Could be useful in the future.

I have several RB411 with green/tan that are puffed up. But they read 560 uf 6.3 volt they also say SJ on them.
What size should I replace them with?
All these boards are just over the 1 yr warranty.

Hi,

You can replace the faulty ones with ones of the same specification. The important bit is '560 uf, 6.3 volts'

We had to replace quite a few (RB750 and RB450) and never had a problem finding the parts. Any decent electronics shop should have them. If not, you could try the RS catalogue online at http://www.rs-components.com/index.html

Rgds,
Mark.

all I can find locally is 680 uf at 10 or 25 volts. will that work?

I have the new 6.3 volt 560 uf caps but I am having a hard time getting the old caps out. I use to do board level repair and never had this problem. I guess since I have not done this in a fer years the technique is forgotten.

It takes a lot of heat to remove them as the ground plane is heavy for these caps.

A trick that I use is to clip the leads short, then heat and remove the cap legs one at a time.
Use the cap body as a lever and rock it.

Then I use a tiny twist drill in a pin vise to remove the solder from the holes.
The drill bit is smaller than the holes so it doesn't damage the hole plating.

Tom

use desolder wick to suck off all the solder then you can just remove the part and have clean holes to put the new one in.

Thanks for help. I have tried with a solder station and wick and a solder sucker (spring loaded vaccum pump)
Even though I have the heat set to full I can't seam to get it hot enough. I did not wan to try a gun because I thought the heat would be too hot and the tips are so big. The tips on the solder station are a point like a pencil not a biger wedge.

I have the can off but still have some of the legs in the hole. Since the board is bad anyway I guess I can try a gun and if I burn the board I have not lost anything. I am starting on the Rb411 since they are $45 boards and not more expensive boards like the 433

Hi,

For some fine work we use a Weller WESD51D (rather pricey) - link - http://www.cooperhandtools.com/brands/C ... 7103191922

But for replacing the caps on the RB750/RB450 units, this unit serves us pretty well (good value Euro 22) - Antex XS25 - link - http://antex.co.uk/product.asp?strParen ... 0&P_ID=823

The real trick is to wait for the tip to get really hot and get a LITTLE bit of solder on it. Also, as Tom (Roc-Noc) said above, clipping the extra bit at the end helps as you can get the hot soldering tip closer to the actual soldering and wait for it to really melt to the inside, then pull gently on the capacitor from the other side of the board. A must is making sure that the board is held in a solid manner vertically to a bench so you can manouver with both hands.

Rgds,
Mark.

680 uF is a special order and takes weeks to get. I have found some suscon 820 uF 6.3V that fit (8x12 mm). Does anyone know if the increased capacitance value will be a problem If the value is larger but the package size is the same.

No problem with 1000uF here. See my very first post.

if you get Suscon, get MG or HG series. Those are better.

if you get Suscon, get MG or HG series. Those are better.

where to buy MG or HG SusCon series in Europe?

680 uF is a special order and takes weeks to get. I have found some suscon 820 uF 6.3V that fit (8x12 mm). Does anyone know if the increased capacitance value will be a problem If the value is larger but the package size is the same.

560, 680 are not very common, you can use 470uF 10 or 16v

Today one of my RB411 died. Three capacitors 560uF/6.3V leaked...
It is somewhat three years old, runing indoors using original Mikrotik power supply over PoE.

I also had a problem with a cap on my RB750G after about 2 years of constant running + it was behind UPS, so I had to change the cap. We had a lot of 450 and 750 boards with same problem. I hope no one would have such troubles anymore.

I just went through our orders for capacitors and have found out, that we have changed almost 300 pcs of them. They were all kinds of 411s, 750, 450, you name it. We've also got some of the older 600 routers; all of them were puffed up.

I think it's a real pity that Mikrotik behaves so unresponsively. They should have let us know about the problem and help us out. Instead they have denied everything even when we alerted them and asked them to help us. They should have identified shipments with the problem and at least send the capacitors and instructions. Fair deal in my opinion would be a 50€ credit for each and every crippled shipped unit. This is how serious companies like Aruba Networks or Ruckus would take care for those who actually makes their money at the frontiers with the end users.

We’ve lost more money on the repairs, replacements and travel costs than we have earned from the sales in two years, just because of these stupid capacitors.
As you can see, good Panasonic capacitor costs 0,113€ if you buy 1000+ http://si.farnell.com/jsp/search/produc ... ku=9691847 . I do not know the Mikrotik supply chain logic, but it must be a pretty cool one.

For soldering, we are using weller 80W station, I think we go with 440°C. It works quite well after you change 50 or so capacitors…

Happy soldering,
Nejc

Well that sucks. I had an 433 that i got rid of cuz it wouldn't power up.. Never checked the caps to see if they were good or not. Damn it!

-mike

If I buy a new rb750 today, will this problem be fixed? Just to know how many that I have to replace before it breaks down.

If I buy a new rb750 today, will this problem be fixed? Just to know how many that I have to replace before it breaks down.

please see the second post in this topic. The problem has long been solved!