On Thu, 4 Jan 2018 22:18:24 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 5:46 PM, wrote:
On Thu, 4 Jan 2018 15:23:28 -0500, "Mr. Luddite"
wrote:


I definitely agree that not everyone should do this. The best way is to
have an automatic transfer box installed to code by a licensed electrician.

That said, I've done this several times, including the house we had in
Florida after Wilma. I have sufficient knowledge of what I am doing but
even so, I stop, check and re-check before firing up the generator and
throwing the breaker that it backfeeds through.

It's illegal, but safe if you pay attention and know something about
house wiring.

Here's a little test that I've even tried on licensed electricians to
see how knowledgeable they a

Your house service is usually 240vac, split phase. Split phase means
two "hot" leads, a neutral (used with both hot legs) and a ground (which
really is tied to the neutral leg. Across the two "hot" leads you have
240 volts which is used for stoves, large AC units, etc. Between either
hot lead and neutral you have 120 volts which is used for your outlets,
lighting, refrig and small appliances. Your panel box is supposed to be
wired to balance the loads as best as possible. So, here's the
question. Let's say:

Leg "A" of the 120 volt supply is drawing 40 amps.
Leg "B" of the 120 volt supply is drawing 30 amps.

How much current is flowing through the common neutral leg that is used
for both legs?

The answer is 10 amps.

Many people assume it is the sum of both current draws or 70 amps in
this example and it's amazing how many "electricians" don't know that.
They don't realize that the two "hot" legs are 180 degrees out of phase,
so the current in the neutral adds algebraically.

That's why the neutral feed from the street to your power panel is the
same size wire as the two hot leads. It will never carry more than what
one hot leg is rated to draw.

I can't imagine any real electrician does not know that.
In fact with the right engineering, the neutral really only needs to
be sized to the maximum unbalanced load.
For example
You are allowed to use 70% for ranges and dryers in dwelling calcs.
OTOH on 3 phase, you may end up actually using a neutral of close to
200% of the ungrounded conductor load because of triplin harmonics.
This became an issue with electronic ballasts and switcher power
supplies.


Only on three phase Wye. 3 phase Delta you don't have to worry about the
neutral.

I've never seen 3 phase service to a residential dwelling. Not saying
it doesn't exist, I just have never seen or even heard of it. Both of
the facilities I had for my company were 3 phase though, one 208v Wye,
the other 480v Delta.

I agree the harmonic problem is just on wye but that is the most
common configuration, 208 or 480.
I think the problem first showed up on 480/277 wye systems where they
had a building full of 277v electronic ballasts.
Then it started showing up in those 208 systems that were feeding 120v
lines in cubicles through the internal wiring with a 5 wire feeder as
PCs started replacing terminals with ferro power supplies and space
heaters.

Delta is always funny stuff, depending on where or even if you land
the ground. Corner grounded is probably the easiest to confuse the
novice. It will look just like single phase until you get your meter
out. (2 pole breakers, white wires etc)

On Thu, 4 Jan 2018 22:27:41 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 6:01 PM, wrote:
On Thu, 4 Jan 2018 13:01:34 -0800 (PST), Its Me
wrote:


That's because electricians are schooled on the mechanics of wiring, but not theory. If a device's tag says it draws 30 amps, they know what size and type wire for the run to it (or where to look in the NEC book to find it), breaker size and type, conduit or not, etc. I'd bet close to half don't understand that the two legs are actually 180 degrees out of phase. Their exposure to theory is very brief, then it moves on to mechanics. Nothing wrong with that. The book tells them what size neutral, too.

That was true in places where training is left to the unions but
places that get actual continuing education for the new guys (and the
old guys) will be exposed to a lot more theory.
Union training is basically the old guys dribbling out what they know
to the new guys over 4 years. Very little new ever penetrates that
cycle.
I remember trying to explain triplin harmonics to a bunch of union GSA
electricians and having them tell me how long they had been wiring and
how I was just a snot nosed kid who didn't know ****.
A week later when their neutrals were burning up, the manager told
them they needed to listen to me.
Nobody had ever seen electronic ballasts and switching power supplies
before the 70s and 80s but they learned.



I am sure some electricians do learn theory however I agree with Its Me.
When new stuff comes along the code is just rewritten in terms of how to
wire for the new stuff. The code tells them when arc suppressors are
necessary, for example, but the electrician doesn't necessarily know why.

I have a fairly solid understanding of electrical wiring and power
distribution. However, I am totally ignorant of what current building
codes are. I wouldn't even consider doing a new residential service or
even a major renovation of an existing service myself. I'd hire a
licensed electrician.

I can't speak for the mobbed up union states but I changed from the
inspector trade association (IAEI) to the contractor group (ECF) many
years ago and I talk to those guys a lot. (they are more fun) They get
a lot of basic theory in their CEUs these days and I have never met
one of them who was confused by neutral loads. It is dealt with
extensively in NEC articles 215 and 220. These are generally the
license holders but we also see a lot of journeymen.

On Thu, 4 Jan 2018 22:45:25 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 7:43 PM, Alex wrote:
Mr. Luddite wrote:
On 1/4/2018 1:07 PM, John H wrote:
On Thu, 4 Jan 2018 12:42:29 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 12:20 PM, wrote:
On Thu, 04 Jan 2018 08:54:03 -0500, John H
wrote:

On Wed, 3 Jan 2018 17:19:35 -0500, "Mr. Luddite"
wrote:

On 1/3/2018 2:28 PM, Its Me wrote:
Light flurries now, the predictions range from a dusting to 1-2
inches.Â* Worse the closer to the coast you get.Â* My BIL at James
Island (Charleston) sent a picture earlier of maybe 1/4 inch and
still falling.Â* Very unusual for them.

It's out of here in a few hours and headed up the coast.Â* Good
luck!



Damn.Â* I was hoping it would dump a foot in Mt. Pleasant, just to
shut
my son up.

Last I heard it is supposed to "explode" as it comes up the coast,
becoming essentially a winter hurricane.

"Bombogenesis" is the technical term, and the popular "bomb
cyclone" is a shortened version of it,
according to our weather folks.

They do seem to just make up names for things these days. I think the
classic was "Super Storm Sandy" to talk about something that was not
even a hurricane, it was just "super" for people who were not used to
tropical weather.
It is far from unprecedented tho. There was a real Cat 3 there in the
30s.
I have certainly seen that weather pattern in DC tho and this is not
even the worst case. The snow would actually be more of a problem if
the "eye" of that low was farther west so your wind was drawing wet
gulf stream air up into the cold front north of you. That is what
gives DC over a foot of snow a day and if it stalls, you
"Knickerbocker" snow.


Up here a Cat 1 hurricane in the summer might be preferable over
what is
going on right now. When you look at this storm on radar it is
developing a very defined rotation as it is winding up and getting
bigger.Â* Snowfall rate here is 2-3 inches/hr and the temp is dropping
like a rock since this morning.Â* Pretty much a white-out out there.

Major flooding in Justin's former town with 4 disabled cars with people
trapped inside, one a woman with 2 kids.Â* Water is over the wheel
wells.
Â* Fire and National Guard are responding.

My old stomping grounds in Scituate is really getting clobbered ...
worst in over 30 years despite improvements in sea walls, etc.Â* A TV
reporter nut was standing on the porch of a house about 30 feet from
the
seawall and he was getting soaked with spray, along with dodging sea
ice
that is being thrown up onto the roofs of houses.

So far we haven't had any power glitches here but I fully expect we'll
lose it in the next hour or so. Wind where I am is gusting 55-60 mph.

Best of luck in all that. I think I'd be getting out the extension
cords and prioritizing my
electricity requirements!


Did that yesterday ... that's why I was firing up the Honda to test.

I have a new plan.Â* If power goes out I am going to shut off the main
breaker and then backfeed the generator output through a 15 amp outlet
that's in the shed.Â* It's on the same branch of the split 240v house
supply as the furnace and a couple of rooms.Â* All my lighting is LED,
so that's a tiny load.Â* The generator will run those plus the furnace
system with no problem and I don't need to have extension cords
running anywhere.



Only problem with that is it's hard to tell when the power is back on.


Turn off the breaker that feeds the shed, turn the main back on and see
if your lights work. If so, shut off and unplug the generator then turn
the breaker that feeds the shed back on.

When Wilma hit in Florida I had a much bigger contractor's generator
that had a 240 volt split phase output. I wired it into the power panel
(illegally) on the load side of the main breaker and just made damn sure
I didn't forget and turn the main back on. It worked fine except it
burned so much gas I would have run out of my supply in a matter of a
couple of days. Only used it for about an hour or less a day to run the
well pump and the water heater so I could take showers. Other than
that, I used the little Honda for the refrig, couple of lights, the TV
and Direct TV receiver.

My 5.5 KW burned about 0.5-0.6 GPH gasoline and more like 8 on propane
running pretty much 24 hours a day at close to full load. Once I
started running propane, it never turned off. I did trip the breaker
now and then when the loads ganged up on me. ;-)

On Thu, 4 Jan 2018 22:48:47 -0500, "Mr. Luddite"
wrote:

I didn't know it was illegal - at least not here.Â* If you are
effectively, and correctly, taking yourself "off the grid" you should be
able to do whatever you want.


It's illegal everywhere I know of ... meaning "not to code". As someone
mentioned there's a risk to line workers who are restoring power if you
stupidly leave the main on while using your generator. I suspect they
are careful to check for "hot" lines that are supposed to be dead though.


Since the codes are usually adopted as law, that makes it illegal.
I agree the power crews should be using safety procedures that prevent
them from getting killed but people screw up. You are more likely to
get your neighbor who is screwing around trying to get his gen set
going with a suicide cord or worse. I was amazed at the things people
were doing around here. One guy was so far out of whack, I told him to
stop trying to feed his panel and just use cords. He is a
fireman/paramedic who should know better too.
In retrospect I think he had a generator that did not have the neutral
bonded, using an existing cable that assumed they were (only
connecting to the generator ground). His neutral to the panel was
floating. He had already blown some stuff up by the time I got there.

On Thu, 4 Jan 2018 22:50:19 -0500, "Mr. Luddite"
wrote:



Harry's playing outside, four wheeling in his driveway in 4 inches of snow.


Ny niece posted a picture on Facebook of a measured 6" a few miles
south of Harry. He may have more than 4" of snow.

On Thu, 4 Jan 2018 22:52:39 -0500, "Mr. Luddite"
wrote:

Don't know if it's still so but I remember in the old days you could
remove the battery from a car once it was running and it continued to
run just fine.

They always warned you not to but I did it on my 69 Corvette and
nothing bad happened. (dead battery, no cables and a borrowed battery
to get it going)
OTOH a new outboard (Yamaha or Mercury) will stop right away if you
disconnect or even have an open cell in a battery. (over voltage)
BTDT ... twice.

On 1/4/2018 11:54 PM, wrote:
On Thu, 4 Jan 2018 22:45:25 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 7:43 PM, Alex wrote:
Mr. Luddite wrote:
On 1/4/2018 1:07 PM, John H wrote:
On Thu, 4 Jan 2018 12:42:29 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 12:20 PM, wrote:
On Thu, 04 Jan 2018 08:54:03 -0500, John H
wrote:

On Wed, 3 Jan 2018 17:19:35 -0500, "Mr. Luddite"
wrote:

On 1/3/2018 2:28 PM, Its Me wrote:
Light flurries now, the predictions range from a dusting to 1-2
inches.Â* Worse the closer to the coast you get.Â* My BIL at James
Island (Charleston) sent a picture earlier of maybe 1/4 inch and
still falling.Â* Very unusual for them.

It's out of here in a few hours and headed up the coast.Â* Good
luck!



Damn.Â* I was hoping it would dump a foot in Mt. Pleasant, just to
shut
my son up.

Last I heard it is supposed to "explode" as it comes up the coast,
becoming essentially a winter hurricane.

"Bombogenesis" is the technical term, and the popular "bomb
cyclone" is a shortened version of it,
according to our weather folks.

They do seem to just make up names for things these days. I think the
classic was "Super Storm Sandy" to talk about something that was not
even a hurricane, it was just "super" for people who were not used to
tropical weather.
It is far from unprecedented tho. There was a real Cat 3 there in the
30s.
I have certainly seen that weather pattern in DC tho and this is not
even the worst case. The snow would actually be more of a problem if
the "eye" of that low was farther west so your wind was drawing wet
gulf stream air up into the cold front north of you. That is what
gives DC over a foot of snow a day and if it stalls, you
"Knickerbocker" snow.


Up here a Cat 1 hurricane in the summer might be preferable over
what is
going on right now. When you look at this storm on radar it is
developing a very defined rotation as it is winding up and getting
bigger.Â* Snowfall rate here is 2-3 inches/hr and the temp is dropping
like a rock since this morning.Â* Pretty much a white-out out there.

Major flooding in Justin's former town with 4 disabled cars with people
trapped inside, one a woman with 2 kids.Â* Water is over the wheel
wells.
Â* Fire and National Guard are responding.

My old stomping grounds in Scituate is really getting clobbered ...
worst in over 30 years despite improvements in sea walls, etc.Â* A TV
reporter nut was standing on the porch of a house about 30 feet from
the
seawall and he was getting soaked with spray, along with dodging sea
ice
that is being thrown up onto the roofs of houses.

So far we haven't had any power glitches here but I fully expect we'll
lose it in the next hour or so. Wind where I am is gusting 55-60 mph.

Best of luck in all that. I think I'd be getting out the extension
cords and prioritizing my
electricity requirements!


Did that yesterday ... that's why I was firing up the Honda to test.

I have a new plan.Â* If power goes out I am going to shut off the main
breaker and then backfeed the generator output through a 15 amp outlet
that's in the shed.Â* It's on the same branch of the split 240v house
supply as the furnace and a couple of rooms.Â* All my lighting is LED,
so that's a tiny load.Â* The generator will run those plus the furnace
system with no problem and I don't need to have extension cords
running anywhere.



Only problem with that is it's hard to tell when the power is back on.


Turn off the breaker that feeds the shed, turn the main back on and see
if your lights work. If so, shut off and unplug the generator then turn
the breaker that feeds the shed back on.

When Wilma hit in Florida I had a much bigger contractor's generator
that had a 240 volt split phase output. I wired it into the power panel
(illegally) on the load side of the main breaker and just made damn sure
I didn't forget and turn the main back on. It worked fine except it
burned so much gas I would have run out of my supply in a matter of a
couple of days. Only used it for about an hour or less a day to run the
well pump and the water heater so I could take showers. Other than
that, I used the little Honda for the refrig, couple of lights, the TV
and Direct TV receiver.

My 5.5 KW burned about 0.5-0.6 GPH gasoline and more like 8 on propane
running pretty much 24 hours a day at close to full load. Once I
started running propane, it never turned off. I did trip the breaker
now and then when the loads ganged up on me. ;-)



The one I had was bigger ... 14 KW, I think.

On 1/5/2018 12:09 AM, wrote:
On Thu, 4 Jan 2018 22:52:39 -0500, "Mr. Luddite"
wrote:

Don't know if it's still so but I remember in the old days you could
remove the battery from a car once it was running and it continued to
run just fine.

They always warned you not to but I did it on my 69 Corvette and
nothing bad happened. (dead battery, no cables and a borrowed battery
to get it going)
OTOH a new outboard (Yamaha or Mercury) will stop right away if you
disconnect or even have an open cell in a battery. (over voltage)
BTDT ... twice.



I know that in many cases the battery in a boat acts as the voltage
regulator.

On 1/4/2018 11:42 PM, wrote:
On Thu, 4 Jan 2018 22:18:24 -0500, "Mr. Luddite"
wrote:

On 1/4/2018 5:46 PM, wrote:
On Thu, 4 Jan 2018 15:23:28 -0500, "Mr. Luddite"
wrote:


I definitely agree that not everyone should do this. The best way is to
have an automatic transfer box installed to code by a licensed electrician.

That said, I've done this several times, including the house we had in
Florida after Wilma. I have sufficient knowledge of what I am doing but
even so, I stop, check and re-check before firing up the generator and
throwing the breaker that it backfeeds through.

It's illegal, but safe if you pay attention and know something about
house wiring.

Here's a little test that I've even tried on licensed electricians to
see how knowledgeable they a

Your house service is usually 240vac, split phase. Split phase means
two "hot" leads, a neutral (used with both hot legs) and a ground (which
really is tied to the neutral leg. Across the two "hot" leads you have
240 volts which is used for stoves, large AC units, etc. Between either
hot lead and neutral you have 120 volts which is used for your outlets,
lighting, refrig and small appliances. Your panel box is supposed to be
wired to balance the loads as best as possible. So, here's the
question. Let's say:

Leg "A" of the 120 volt supply is drawing 40 amps.
Leg "B" of the 120 volt supply is drawing 30 amps.

How much current is flowing through the common neutral leg that is used
for both legs?

The answer is 10 amps.

Many people assume it is the sum of both current draws or 70 amps in
this example and it's amazing how many "electricians" don't know that.
They don't realize that the two "hot" legs are 180 degrees out of phase,
so the current in the neutral adds algebraically.

That's why the neutral feed from the street to your power panel is the
same size wire as the two hot leads. It will never carry more than what
one hot leg is rated to draw.

I can't imagine any real electrician does not know that.
In fact with the right engineering, the neutral really only needs to
be sized to the maximum unbalanced load.
For example
You are allowed to use 70% for ranges and dryers in dwelling calcs.
OTOH on 3 phase, you may end up actually using a neutral of close to
200% of the ungrounded conductor load because of triplin harmonics.
This became an issue with electronic ballasts and switcher power
supplies.


Only on three phase Wye. 3 phase Delta you don't have to worry about the
neutral.

I've never seen 3 phase service to a residential dwelling. Not saying
it doesn't exist, I just have never seen or even heard of it. Both of
the facilities I had for my company were 3 phase though, one 208v Wye,
the other 480v Delta.

I agree the harmonic problem is just on wye but that is the most
common configuration, 208 or 480.
I think the problem first showed up on 480/277 wye systems where they
had a building full of 277v electronic ballasts.
Then it started showing up in those 208 systems that were feeding 120v
lines in cubicles through the internal wiring with a 5 wire feeder as
PCs started replacing terminals with ferro power supplies and space
heaters.

Delta is always funny stuff, depending on where or even if you land
the ground. Corner grounded is probably the easiest to confuse the
novice. It will look just like single phase until you get your meter
out. (2 pole breakers, white wires etc)


Not familiar with that. The majority of the systems we built were
designed to run on 480v, 3 phase. All the main breakers, fused
disconnects, motor starters, etc. were three pole. Ground was run
separately. We used a dedicated control transformer in each power
cabinet to generate whatever the low voltage control wiring was ... 120v
in the early days but later 24 volt. IIRC, the control transformer on
the 120v systems was a 480v/240v step down with a center tap, providing
a neutral.

On Friday, January 5, 2018 at 5:25:36 AM UTC-5, Mr. Luddite wrote:
On 1/5/2018 12:09 AM, wrote:
On Thu, 4 Jan 2018 22:52:39 -0500, "Mr. Luddite"
wrote:

Don't know if it's still so but I remember in the old days you could
remove the battery from a car once it was running and it continued to
run just fine.

They always warned you not to but I did it on my 69 Corvette and
nothing bad happened. (dead battery, no cables and a borrowed battery
to get it going)
OTOH a new outboard (Yamaha or Mercury) will stop right away if you
disconnect or even have an open cell in a battery. (over voltage)
BTDT ... twice.



I know that in many cases the battery in a boat acts as the voltage
regulator.

Yes, a large capacitor. It seems that most boat motors have fairly simple charging systems, unlike a car's alternator/voltage regulator. As far as taking the battery out of a running car, I agree that it was possible back in the day, but I sure wouldn't chance it in a modern car. Too many controllers (computers) spread around in today's cars. The battery still smooths out whatever is coming out of the alternator. You could brick your car.