6 ms·

> We are investigating whether fitting Uninterruptable Power Supplies to each signalling location would have prevented this failure, although it is also possibl

> We are investigating whether fitting Uninterruptable Power Supplies to each signalling location would have prevented this failure, although it is also possible they would have had to shut down to protect themselves too, as happened at another location during the same event. This specific remark sounds rather amateurish. This is part of the reason UPSes were invented. A Double Conversion Online UPS would have been able to handle this situation just fine.

wilhil 7y ago
I worked for an ISP that was deploying switches nationwide... We got a lot of space in BT Telephone Exchanges and thought nothing more of it. I have never seen such dirty and bad power! Literally once a week we had to go to exchanges to reset fuses that had tripped. We then started deploying (rather entry level) UPS to all locations and the problem just disappeared completely... we then invested in more high end UPS systems, but, yeah - dirty power is a big problem and UPS help.
- Aloha 7y ago
  I'm surprised CO gear was not running on -48v rather than AC power
  - viraptor 7y ago
    Is DC actually common these days? I haven't been to a physical datacenter in a decade or do, but I remember almost everything running on AC.
    - wilhil 7y ago
      I'm an IT and networking guy... This is one thing that got on my nerves completely - most equipment comes as AC or DC, and I'm never sure what to order, so, I usually go for the AC one as it's the safe choice
    - Aloha 7y ago
      It is in Telecom Applications.
isodude 7y ago
Or by development under time, like Forsmark in Sweden where an adapted UPS surge protection almost caused a meltdown. When a surge happened 12 security systems was disabled. From what I heard the diesel didn't because it was searching for incoming voltage it could adapt to. > De flesta av felen berodde på att det batterisäkrade nätet hade överspänningsskydd, som skyddade komponenten i stället för funktionen. [0] Also mentioned in english [1] [0] https://www.nyteknik.se/energi/hardsmaltan-var-nara-2006-6422678 https://www.nyteknik.se/energi/hardsmaltan-var-nara-2006-642... [1]: http://www.castor.de/english/2006/0820.html http://www.castor.de/english/2006/0820.html

wilhil 7y ago

I worked for an ISP that was deploying switches nationwide... We got a lot of space in BT Telephone Exchanges and thought nothing more of it. I have never seen such dirty and bad power! Literally once a week we had to go to exchanges to reset fuses that had tripped. We then started deploying (rather entry level) UPS to all locations and the problem just disappeared completely... we then invested in more high end UPS systems, but, yeah - dirty power is a big problem and UPS help.

Aloha 7y ago
I'm surprised CO gear was not running on -48v rather than AC power
- viraptor 7y ago
  Is DC actually common these days? I haven't been to a physical datacenter in a decade or do, but I remember almost everything running on AC.
  - wilhil 7y ago
    I'm an IT and networking guy... This is one thing that got on my nerves completely - most equipment comes as AC or DC, and I'm never sure what to order, so, I usually go for the AC one as it's the safe choice
  - Aloha 7y ago
    It is in Telecom Applications.

isodude 7y ago

Or by development under time, like Forsmark in Sweden where an adapted UPS surge protection almost caused a meltdown. When a surge happened 12 security systems was disabled. From what I heard the diesel didn't because it was searching for incoming voltage it could adapt to. > De flesta av felen berodde på att det batterisäkrade nätet hade överspänningsskydd, som skyddade komponenten i stället för funktionen. [0] Also mentioned in english [1] [0] https://www.nyteknik.se/energi/hardsmaltan-var-nara-2006-6422678 https://www.nyteknik.se/energi/hardsmaltan-var-nara-2006-642... [1]: http://www.castor.de/english/2006/0820.html http://www.castor.de/english/2006/0820.html