nanog mailing list archives

Re: Comcast outages continue even in areas with PG&E power restored


From: Jeff Shultz <jeffshultz () sctcweb com>
Date: Wed, 16 Oct 2019 13:37:43 -0700

We use 12 and 48 port VDSLAM's similar to that at some of our remote
locations, and we do generally line power those.

But before those came on the market we were putting out remote
cabinets that could support up to 144 subscribers fed off the same
sort of cards you would find in the CO.

I don't know our power budget per customer, but it's not unusual to
have 20 or more amps of capacity (probably overkill, likely because
that was the size available) at 48V in a cabinet. Because the CO cards
aren't hardened, the cabinet must be - and have some HVAC type
capabilities as well - at least fans.

We're now feeding line power out to some of the 12 and 48 port devices
like you linked to from some of those remote cabinets.

It's all about shrinking loop lengths until we can get both the time
and funds to put fiber in the ground everywhere.

On Wed, Oct 16, 2019 at 1:06 PM Michael Thomas <mike () mtcc com> wrote:

After some poking around, I found this gizmo. It says that it can use
between 1-8 pairs to power it from the co. If there was already a home
run to the co (which is almost certainly true in my case), it seems like
that would be a cheaper option? Then you just have one diesel generator
at the co that charges the batteries.


https://portal.adtran.com/pub/Library/Data_Sheets/International_/I61179918F1-8_1148VXP.pdf

Mike

On 10/16/19 12:09 PM, Jeff Shultz wrote:
On Mon, Oct 14, 2019 at 4:26 PM Michael Thomas <mike () mtcc com> wrote:

On 10/14/19 4:16 PM, Sean Donelan wrote:
On Mon, 14 Oct 2019, Michael Thomas wrote:
Of course this is a lot of conjecture on my part... be glad to be
clued in by folks in know.
An old news story, but telco's usually have backup batteries in their
outside plant, cell towers, etc.  During power outages, they shuttle
small generators between outside cabinets to re-charge the batteries.
Remote Terminal Units (RTUs) use local power, i.e. look for the
utility meter nearby.  There is often a generator plug and battery
cabinet next to the RTU. They aren't powered from the central office.
Interesting! And so primitive! So they go to all of the expense of
laying fiber, but not power too?
Note: small local telco experience speaking below:

Telco's tend to have experience with fiber, but probably not the
construction and transmission of the sort of power plant that would be
required to keep a bunch of  48V cabinets up and running reliably. We
certainly don't. Besides, an advantage of fiber is that hopefully the
copper thieves won't bother it.

  By definition a remote terminal/cabinet is going to be... remote. Far
more simple to install commercial power, and then haul out a generator
if the battery string in the cabinet appears to be in danger of
dropping below about 46v.

We do run some 360v DC at micro-amp levels out to equipment like ONT's
and remote 12 and 48 port remote VDSLAM's. But that's over existing
24-26 ga. plant. Frequently using multiple pairs to avoid excessive
voltage drop over distances.

Primitive is tested and works.




-- 
Jeff Shultz
Central Office Technician

-- 
Like us on Social Media for News, Promotions, and other information!!

   
<https://www.facebook.com/SCTCWEB/>      
<https://www.instagram.com/sctc_503/>      
<https://www.yelp.com/biz/sctc-stayton-3>      
<https://www.youtube.com/c/sctcvideos>













_**** This message 
contains confidential information and is intended only for the individual 
named. If you are not the named addressee you should not disseminate, 
distribute or copy this e-mail. Please notify the sender immediately by 
e-mail if you have received this e-mail by mistake and delete this e-mail 
from your system. E-mail transmission cannot be guaranteed to be secure or 
error-free as information could be intercepted, corrupted, lost, destroyed, 
arrive late or incomplete, or contain viruses. The sender therefore does 
not accept liability for any errors or omissions in the contents of this 
message, which arise as a result of e-mail transmission. ****_


Current thread: