We have recently purchased a batch of 6 routerboard 493ah and 433ah. After we deployed several of these we found that whenever their was a power flicker the boards would hang rather than reboot. They require that you kill the power for 30 to 60 seconds before they will reboot. Upon further investigation we learned that this problem is aknowleged by Mikrotik and is a problem with the capacitor on all of the 400 series Routerboards. Is this a known issue with these boards? Is there a quick fix?
This must be old stock as this was fixed a long time ago! If it is indeed the same capacitor problem, MT will replace these under warranty.
Is there a way to determine manufacture date based on the serial number?
You can send the serial number to MT to confirm is from the known batch, but ultimately it is the reseller you bought them from that should be providing you with replacements under their warranty agreement with you. They in turn will get new ones from MT.
Ron
The quick fix is to replace a capacitor. The problem is that it is very small, requires special tools, and a bit of skill.
This is a well known problem that was addressed and fixed last year.
In the RB433/AH you must change capacitor C828 to: ceramic capacitor, type 0805, 1uF
See this thread: http://forum.routerboard.com/viewtopic.php?f=3&t=3868
We have been testing samples of our new RB4xx inventory as it comes in and Mikrotik has not sent us any boards with the old cap values since last December.
And we never received RB493AH boards with the bad capacitor so I am surprised to hear that you received some. I thought that they were all sent out with the correction.
Tom