Connect with us

Lots of devices won't turn on now after power outtage.

Discussion in 'Troubleshooting and Repair' started by shelzmike, Jul 5, 2012.

Scroll to continue with content
  1. shelzmike


    Jul 5, 2012
    I am the IT Specialists for the company I work for. Over this past weekend, we had crazy storms that knocked power out for days to us. All of my networking equipment is powered through either a high end APC UPS, or a smaller APC UPS Surge protector, and then finally a couple are powered through a panamax surge protector. Now, I realize that I can get these devices replaced from from APC and Panamax; however, I am curious if there is anything that I can do to get these back online while I am waiting.

    I have 5 devices, which all happen to be my smallest networking devices, which will no longer turn back on. Two of them are the exact same device but were housed in two different locations on two completely different circuits in two separate office buildings. They are this device: TrendNet TPE-S44 Power over Ethernet Switch. Additionally, I have two Engenius Wireless Bridges that I have never had problems with until now, and a little Cisco wired router.

    I took the board out of the Cisco router and tested the capacitors and out of the 3, 2 have something like 2 ohms and the other is infinite. The one closest to the battery is the one that is infinite, does that indeed mean it is "fried"?

    I know enough about electronic components to be dangerous, but nothing that would allow me to diagnose any further. Does anyone have any advice for me at all? Thanks!

  2. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    If you have done a comparative analysis of several devices, then (within certain bounds) any differences are pointers to problems.

    Capacitors have a resistance that goes up and up and up the longer you measure them. A steady (especially low) reading indicates they're shorted or (more likely) there is something else in the circuit that has a low resistance. Te capacitor reading a high resistance *may* be fried, but it may also be something else in the circuit.

    Posting photos of the areas concerned would be helpful.

    Also look for burn marks, components that seem to have changed colour or white residue on larger components. Sometimes you can spot components that have literally exploded or fractured.
  3. shelzmike


    Jul 5, 2012
    Thanks for the reply so quickly. I suppose comparative analysis makes sense - the device in question actually is not one of the ones I have multiple of, so I will have to dig into those. I will try to find time to take some pictures since they will help. I am still playing catchup from everything that has happened over the past week with the storms and whatnot. I did want to mention that on this device that I do not see any obvious burns, bulged components or anything like that - looks perfectly clean actually, but looks can be deceiving. I will post back shortly. Thanks!

  4. JonathanAnon


    Mar 22, 2012
    Wow that sounds like some storm..

    - For the UPS and Surge protection, could you not just leave these out and plug the devices (presumably servers?) straight in to the mains... And then reintroduce the UPS and surge protection when you get them fixed..
    - You could replace the power over Ethernet by running a long long power extender cable ??
    - Could you recreate the wireless bridged temporarily with a long Ethernet cable, or maybe (if you had broadband on both sides) you could create a temporary VPN over the Internet. ? What services does the now (presumably) isolated side of the network need access to?

    Have you checked all the fuses in all the devices? Without physically see the locations of the devices, and distances between them, it's hard to suggest what might work..
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day