[TowerTalk] Fwd: shack wiring

Jim Thomson jim.thom at telus.net
Tue Aug 3 23:25:14 PDT 2010


Date: Tue, 3 Aug 2010 03:13:38 +0200
From: "DF3KV" <df3kv at t-online.de>
Subject: Re: [TowerTalk] Fwd:  shack wiring
To: <towertalk at contesting.com>
Message-ID: <1Og64a-0yAPTc0 at 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 at contesting.com
[mailto:towertalk-bounces at 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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