Date: Tue, 3 Aug 2010 03:13:38 +0200
From: "DF3KV" <df3kv@t-online.de>
Subject: Re: [TowerTalk] Fwd: shack wiring
To: <towertalk@contesting.com>
Message-ID: <1Og64a-0yAPTc0@fwd06.t-online.de>
Content-Type: text/plain; charset="us-ascii"
What happens to the other 8 homes mains voltage if you fire up that YU148?
73
Peter
## ha ha. I had the power co guy's out here a few months back..and asked them
the same thing. Their answer was... "go ahead and burn it right off the pole" .
Here in NA, we are being sold a bill of goods. Everyone has '200 A'
service...
but the drop wire into each home is just 1-0 stranded AL.... which then gets
spliced into 3-000 stranded CU. .. then into the meter base [which is the most
mickey mouse, piss poor design you ever saw, regardless of who makes em] ..
then into main 200A panel.. which imo, they all use undersize buss bars.
## they put a clamp on ammeter on the pole..and it was sucking 112 A at 5
pm.
50 kva / 240 V = 208 A [ in reality, the xfmr V would drop down]. 208A /
9 x homes
= 23 A each. Yet, we are all getting..'200A service' . An electric
stove..with all 4 x top
burner's on full bore + oven is close to 10 kw. A clothes dryer sucks another
5 kw. Hot water
tank is another 3/4.5 kw.
Toss in any electric heat, neighborhood grow-ops, welding eq, etc... and you
wonder
why more don't burn up. Most folks here have converted to natural gas for
heating,
and hot water. I find it amusing that folks who 'want to go green'.. and 'save
the
environment' all just figured out that if they used a clothes line.. they
wouldn't be
sucking 5 kw with a clothes dryer. Yet city hall in a town north of me, has
banned
back yard clothes lines ! Some woman is taking em to supreme court.
## power co guys tell me they over fuse these pole pigs by a whole bunch.
Even though the
xfmr's are all marked 14.4 kv... in fact they are 12.5 kv. A 4 A fuse in the
hv primary would suffice...
but they use 6-9 A slo blow types. IF they were fused correctly, the hv
fuse would blow open 1st..
and no xfmr fires would ever happen. A yr ago, one xfmr did explode, oil on
fire.. and somebody happened
to get it on camera..good pix... with solid yellow flames from xfmr..right down
to the sidewalk, burnt
a parked car to a crisp too. The pwr eng at work told me at one of our
telco's in Vancouver, they
burnt all 3 x xfmrs right off the pole ! They were all 1600 lbs..EACH. Xfmr's
all came crashing down to the
sidewalk..along with the pole.
## In answer to ur question.. they said they have bigger xfmr's like 75 kva-
100 kva and 125 kva.
Plan B was to install 2 x xfmr's on one pole... and split the 9 x homes between
em. I suggested
1 xfmr for myself... and the 2nd xfmr for the other 8 x folks. SSB is never
an issue, lights don't blink.
But they do on CW... or during pulse tuning. A big C filter cap.. like
100-400 uf really helps a lot..with
dynamic B+ regulation. Biggest problem is the long AL drop line..and V drop
from it.
## a fellow at work has a lot of 3 phase power tools, 7.5 hp air compressor,
9 hp planer, etc..for his
wood working side line business. When he originally built his home... the
power co installed
a 10 kva xfmr. [ he's in the country, and one xfmr just for himself]. He
blew it up, and they replaced with a
25 kva unit. The same fellow at work used an electronic
single phase.. to 3 phase converter... which still works VERY well to this day.
That's a good fix for the
fellow on here who runs a machine shop in queens NY. You get all the
advantages of 3 phase power for
motors, etc.. without the hassle of bringing 3 phase power.... which isn't
gonna happen anyway.
You have to be living on a main road, etc, to get 3 phase power around here.
All condo's and apartment
buildings all have 208/120 3 phase. .. and all are on main roads... or side
streets,, where condo's and apts
line both sides of the street.
## My bro in law has 3 phase power for his art studio he rents. He pays
through the nose.. just to have it.
Basic monthly charge is huge... and that's on top of the usage fee. [KWH x
XXX]. IE: even if you shut off main
breaker for a month, you still get a bill for having it.
Later... Jim VE7RF
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Thomson
##### Here, we have 9 x homes hanging off one 50 kva xfmr. This part of
town
is all on poles. My drop wire is a mid span drop...between 2 x poles.
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