Hi,
Recently I have had 2 x Rb411AH’s fail during heavy weather, both failed in the same way the NIC failed and no connectivity. While the NIC was not working the WLAN continued to function along with the routerOS but no matter what we tried we could not get the LAN ports working again.
I cannot see any damage on the boards themself can you recommend anything to get them going again?
Cheers
Cameron
You need to think about proper grounding for them in the future.
Reset the configuration, upgrade MikroTik RouterOS to 4.5 and RouterBOARD firmware by /system routerboard upgrade and /system reboot.
If it does not help, return boards to your supplier.
Hi,
I have tried everything you have mentioned, I have just purchased two new units to replace them. I did have them grounded but could you provide a good example?
Cheers
Cameron
Grounding is an art that can be learned with experience. Just keep in mind that you want static electricity to discharge through the tower / ground rod / ground wire, instead of the electronics inside your equipment. So always make your grounding effort more inviting to electricity than the equipment’s own ground (through its circuits).
For example a well grounded tower will have at least several ground rods into the earth. Even better would be a ring of ground rods around it and all bonded together. Guy wires also need to be grounded and bonded together.
A poorly grounded tower will just have its base buried in concrete with no ground rods. Sometimes it is difficult to tell without losing some equipment first.
Good grounding practices on a tower include bonding your equipment to the tower at both the top and the bottom and every 50 feet to the cable shield.
Now you can see why the tower needs a really good ground or else your equipment will take over the grounding for the tower.
Also make sure that your source of electricity is properly grounded and ideally it should share the same ground as the tower so there is not a difference between the two.
I lost about 10 APs on a single tower within 45 days two summer’s ago. I had been on that tower for 7 years already with no previous problems. After the second storm took out 5 radios, I thoroughly investigated my grounds and found the electrical power main had lost its single point ground through corrosion. I was reading about 1 Kohm between the ground rod and the power ground.
We buried three ground rods from the power area to the tower and bonded all together with #2 copper wire and then weatherproofed it all. No problems since.
Good luck,
Tom
So are you saying that Mikrotik will replace lightning damaged RouterBoards under warranty? I thought that the warranty only covered manufacturing defects?
Tom
Tom,
Issue is the units that have died have been on the roof’s of the clients and the Unit that died this week I was standing next to it during the storm and the closest strike was 5 km away during the entire event.
I will try gound the units a little better and maybe run a second gound to the ground.
Cheers
Cameron
No, Tom is correct, Mikrotik will not replace lightning damaged devices for free.
I’ve seen a couple of NIC failures like this at moutaintop sites. Even with grounding, you can get charges that will build up during storms and take out the NIC ports. We solved this by adding cat5 lightning/surge protectors that protect the data lines as well. They are widely available from various Mikrotik distributors.
can u tell how to repair those devices 411 AH.,433 AH &7 11 , im have lot of boards damaged due to lightning..
hello sir, i want ground my roof top tower, i want to know the if my lighting arrestor touches the tower will cause damage to my tower equipments during lignthing…?
may i ground the router board and minipci card earthing using same copper cable…?
so, is it is possible to replace or repair the devices at some with you
I skimmed the thread; so this might have been mentioned. Always use STP ethernet cable. Otherwise you will blow ethernets with lightning strikes from 4-5 miles away. We are in Oklahoma (US), which is the 2nd largest lightning state behind Florida. When I started our WISP, we used just used UTP cable on customer CPE installs and found that we were losing ethernets on a very frequent basis during storm season. We started using STP and a decent POE injector that has an electric ground; such as Ubiquti’s POE-15/24. Our CPE lightning repairs dropped by a factor of 10.
Now on tower, we usually go more extreme. ROC-NOC was right on. On our water tower installs, we use a copper bus bar up at top of tower. All antennas, coax, and lightning arrestors are bonded to the bar. We run stranded #2 copper (not very cheap stuff; about $3/foot) down to the base and drop 3-4 8ft ground rods and bond them together. Also bond with the water tank. Then we take some #4 or #6 ground and run it from rods to enclosure/building. We add a good quality ethernet surge protector; such as the ones from L-com. These are then bonded with the ground wire along with any metal enclosures, etc. If done right, you can take almost a direct hit. Now there is more of a science to grounding; and the cell phone companies actually go much further in their grounding. So I know there is much more you can do. I find just doing this limited grounding adds an extra $300-$600 to the cost of a site installation. It is not uncommon for a cell phone company to spend 4-10k on grounding.
Damaged chips are MICREL KSZ8041NL on older boards and Atheros AR8012 on newer boards. They are relatively cheap to replace.