On Thursday, November 9, 2017 at 7:21:23 AM UTC-5, Jim Wilkins wrote:
Yes, it does sometimes raise suspicions. I know what I know about the phone
system and its backup power because I spent two years contracting for AT&T
in about 30 local offices in the NY metro area. Part of my job was verifyi
ng power budgets and delivery to AT&T's colocation cages. The stuff they ha
ve in those places is impressive, and it works.
My knowledge the cable company power situation is empirically gained. Five
hours (give or take a very little) after the power fails, the cable (and da
More interesting (and I have to get some better contacts to find out more)
is the electrical utility. During a major outage, I had a talk with a super
visor. I was wondering why it seemed so damned hard to find the busted wire
or blown fuse. You know where the lights are on, you know where the lights
are out. Look at a friggin map and fix it. "Not so easy" he said. The noti
on that there's any sort of "grid" in the local system is just a fantasy. A
real diagram would be more like a picture of a bowl of spaghetti. I know,
for instance that there are loops and parallels and distributed transformer
But still, it seems to me that there could be (at the cost of a few bucks e
ach) a transponder in, say, each transformer that would let them know it's
got power. Much easier than driving around with a flashlight to look at the
poles & wires.
But still, it seems to me that there could be (at the cost of a few
bucks each) a transponder in, say, each transformer that would let
them know it's got power. Much easier than driving around with a
flashlight to look at the poles & wires.
The easiest and cheapest solution is to see who calls to complain.
On Friday, November 10, 2017 at 8:29:08 AM UTC-5, Larry Jaques wrote:
Cheapest, but hardly efficient. Again, transponders would be cheap and coul
d provide otherwise useful telemetry (voltage, load, etc). Our local utilit
y (PSE&G) has installed 200W solar panels on many poles. Lots of poles - 40
MW total. Some of these units have antennas on them. I don't know whether t
hey are in constant communication to a central computer, but if they are, t
hey could provide some useful information about outages. But I don't think
they use that information. They just wait for enough people to call and the
n send out a car.
Utility installed "smart meters" here several years ago. They use one
of the cell networks (my understanding) to report meter readings and
such several times a day. When power goes out they are suppose to be
able to still send out a death gasp.
I gave up calling in outages when they said I would be charged for the
service call if they deem it isn't there fault...
Cheapest, but hardly efficient. Again, transponders would be cheap and
could provide otherwise useful telemetry (voltage, load, etc). Our
local utility (PSE&G) has installed 200W solar panels on many poles.
Lots of poles - 40MW total. Some of these units have antennas on them.
I don't know whether they are in constant communication to a central
computer, but if they are, they could provide some useful information
about outages. But I don't think they use that information. They just
wait for enough people to call and then send out a car.
We haven't seen a quick, easy solution because the issue is very
"Deployment of BPL has illustrated a number of fundamental challenges,
the primary one being that power lines are inherently a very noisy
This is a somewhat similar system in which independent nodes
intercommunicate over a single radio frequency using a collision
detection and avoidance protocol similar to Ethernet's.
On Friday, November 10, 2017 at 1:05:06 PM UTC-5, Jim Wilkins wrote:
Oh, fer crissake, they're just not trying very hard. Our water company rece
ntly did a third upgrade of our meter sender. The first could be read by a
car driving by. The next could be read by helicopter, and the current on co
mmunicates directly with a satellite, so they tell me.
Power monitors wouldn't have to transmit a whole lot of data to say "I am a
Oh, fer crissake, they're just not trying very hard. Our water company
recently did a third upgrade of our meter sender. The first could be
read by a car driving by. The next could be read by helicopter, and
the current on communicates directly with a satellite, so they tell
Power monitors wouldn't have to transmit a whole lot of data to say "I
They aren't going to waste money on an incomplete temporary solution.
Water meters don't need to track and report phasing and overloads in
real time or command load shedding.
On Friday, November 10, 2017 at 1:36:05 PM UTC-5, Jim Wilkins wrote:
As if sending managers out in cars in a storm isn't expensive or half-assed
As I said, the solar panels they have already installed appear to have some
sort of telemetry capability (I assume based on the fact that there are an
tennas attached). I can imagine that being useful to locating faults. Or no
Meanwhile, in the past few years, my electric service has been much improve
d, since they did some pretty big infrastructure upgrades. They raised the
HV on our poles from 8KV to 13KV (half the I^^2R loss). In doing that, they
replaced every transformer, several poles and the substation transformers.
Where my line voltage often dipped as low as 104 volts on a regular basis,
it is now rock solid 117V. Even when it rains and the wind blows.
When they replaced the transformers, each had a 8/13KV switch, set to 8KV.
After everything was in place, they brought in more trucks than I knew they
had, so that there was at least one bucket truck for every two transformer
s. They shut off the power for less than ten minutes to switch every one of
them. Pretty impressive.
Probably the same reason that telephone central offices run on 48V DC, nominal, to stay within the "Less than 50V" section of the electrical codes. (Actual voltage is somewhat above that except when actually running on battery power.)
On Friday, November 10, 2017 at 7:20:31 PM UTC-5, Robert Nichols wrote:
minal, to stay within the "Less than 50V" section of the electrical codes.
(Actual voltage is somewhat above that except when actually running on batt
I haven't done ony research on the (not THAT interesting)., but I bet that
the 48V "battery" - actually -48V - predates any "Less than 50V" in the cod
e. I spent a couple of weeks verifying test procedures at Bell Labs, where
they have samples of EVERY device ever approved for connection to the PSTN.
They go all the way back to stuff from the 19th century. All of them run o
n the same -48V system.
I have to say (probably have said it here before) that it's remarkable that
you can take one of these ancient phones and plug it into a modern phone s
ystem and it still works. The same system can provide multi-megabit data se
rvice over the same wires. The Bellcore standards are pretty rigid, but all
ow for future improvements without obsoleting existing equipment.
Back when I was working there (started in No. 5 Crossbar, 40+ years ago) I was told that's the reason it's called "-48V" rather than "-50V" even though the actual voltage is more like -52V or -53V. I just accepted that.
In that "stuff from the 19th century", the central office didn't supply power to the subscriber phones. You had your own dry cell batteries to power the carbon microphone, so whatever voltage ran the CO switchboard was irrelevant.
That was an example, similar to what Batteries Plus recently quoted to
So far the TV stations and the landline and cellular services have
stayed up on their batteries and generators. The Northeast has to
prepare for both tropical hurricanes (TS Sandy) in summer and arctic
ice storms in winter. I have both 3G and 4G wireless internet.
Week-long storm outages tend to occur in relatively narrow strips,
like between all snow and all rain, or wind and flood damage near the
coast. They aren't regional like power generation blackouts which we
haven't suffered yet, though our safety margin is shrinking due to
political opposition to coal, nuclear, pipelines and Canadian hydro.
Food-heating. I didn't write 'cooking' because it doesn't get hot
enough to fry.
Aren't Leftists wonderful? No to this, no to that, no to the other,
then SAVE ME from everything--after they've hosed any systems which
Maybe we need two governments. One large one to serve just the
Leftists covered by massive taxes paid only by them, then a small one
to serve the actual Americans, with few taxes paid only by us.
Evidently not. <sigh> But if you wanted to camp out in your living
America rose from abnormal origina. The nation didn't grow organ-
ically or gradually from indigenous tribes--like, say, the French
_Forbes_ says that Maine's power problem is the grid, not generation:
[Nov. 5, 2017]
"Nearly half of the people living in Maine spent a significant part of
last week in the dark after a storm caused widespread power outages.
"Central Maine Power, a subsidiary of the Spanish utility holding
"...Solar companies did not cause the prolonged power outage in Maine.
Neither did deregulation. CMP did. Yes, the same utility company with
the slogan "Flip a switch and we're there."
incompetence and lack of planning turned what should have been a short
power outage into a prolonged and painful experience. The mega-scale
administration would not have made an iota of difference.
"The CMP Maine Power Reliability Program (MPRP) certainly did not keep
What do you think? Are they right?
Not enough information to tell.
However, I read the Forbes article to imply that there had been decades of
deferred maintenance on Maine?s power distribution system, and MPRP was the
funding vehicle chosen to make the down payment of bringing the distribition
system up to snuff.
In Puerto Rico, they had the same problem, but no MPRP equivalent, and the
hurricanes blew the existing ramshackle system into the sea. Total
replacement is underway. Probably take a year.
Fortunate for Maine that they are too far North for real hurricanes.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.