# Generator Hookup

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Teodor Väänänen
Guest

Wed Mar 10, 2010 9:38 pm

pawihte wrote On 2010-03-10 10:04:
Quote:
Jon wrote:
What do I know?

What don't I know. Obviously more than all of you combined.
Is
there an engineer in the house? Then find out where I went
wrong
with this
http://mypeoplepc.com/members/jon8338/math/

I didn't go wrong with any of it. Then what makes any of you
think I

The 240 volts come from two 120 volt signals phase shifted by
half a
period. Am I right? Am I wrong? How many of you know that?
Or are
you just pretenders?

You aren't right, IIRC, electricity to homes in the US is almost always
a balanced feed from a center-tapped secondary of a transformer
(120-0-120, or 240 if you only use the outermost leads), AFAIK 3-phase
is only used in distribution and industry settings.

Quote:
With 3-phase service, by what fraction of a period are each of
the
phases shifted? ANSWER ME. What is the maximum peak-to-peak
voltage?

120 degrees. I live in the EU, so here the voltages are 235V between
phase and neutral, and 400V between two phases. From this we can deduce
that the peak voltage is 332V phase-neutral and 565V phase-phase and
that the peak-to-peak voltage is twice that (664 and 1131 V,
respectively). Yes, I know the voltages are different in the US, but the
ratios should remain the same, i.e. the ratio of the voltage between
phase-neutral vs. phase-phase is in the ballpark of 1.702.
The peak voltage is the rms voltage times sqrt(2), while the
peak-to-peak voltage is the rms voltage times sqrt(.

Jon, have you taken these potential high voltages (i.e. ~3x normal) into
account when choosing the relay you use? If Murphy's law is invoked when
the mains come back on line, you might find yourself in a situation
where your genny is 180 deg off wrt to mains.

Also, have you tested your design for all the faults that might occur?
The likelihood of a fault isn't the issue, but how your design behaves
is. The rule you must follow is that any failure must be a right-side
failure (fail-safe, i.e. fails in a manner which renders the circuit
safe), you may under no circumstances allow a wrong-side (i.e. fails in
a manner which renders the circuit unsafe) failure to occur. Your and
others lives, health and safety depend on it.

Quote:
posting, but I think it's time someone other than those who have
replied told you where you stand. You were given good advice and
vital cautions time and again. But you not only ignored them, but
kept responding with unwarranted belligerence. Your attitude
obviously kept others from following up with more good, patient
guidance.

You may be good at math but you know so little about
electrical/electronics engineering that you don't even know how
little you know. Those challenge questions of yours are so
elementary that I doubt anyone would dignify them with answers.
It's like asking a group of A+ high school students if they know
to spell 'apple'.

So do yourself a favor. Go over this thread and the previous
ones. Check the replies. If you don't understand or don't agree
with some points, ask specific questions in a civil manner and
read the replies with a receptive attitude.

Well, I tried (see above). Personally, I would leave the design of the
circuit to professionals, because even though I'm educated in
electronics and know my way around digital logic and computers, I know
that the design of the circuit is advanced enough, even by my standards,
to warrant a pro having a looksie at it and utter his approval or GTFO...

/Teo.

--
Teodor Väänänen | Don't meddle in the affairs of wizards,
<teostupiditydor_at_algonet.se> | for you are good and crunchy with
http://www.algonet.se/~teodor/ | ketchup.

JosephKK
Guest

Wed Mar 10, 2010 10:51 pm

On Wed, 10 Mar 2010 00:33:53 -0500, "Jon" <jon8338_at_peoplepc.com> wrote:

Quote:
What do I know?

What don't I know. Obviously more than all of you combined. Is there an
engineer in the house? Then find out where I went wrong with this

http://mypeoplepc.com/members/jon8338/math/

I didn't go wrong with any of it. Then what makes any of you think I know

The 240 volts come from two 120 volt signals phase shifted by half a period.
Am I right? Am I wrong? How many of you know that? Or are you just
pretenders?

Single phase 240 V center tap grounded.
Quote:

With 3-phase service, by what fraction of a period are each of the phases
shifted? ANSWER ME. What is the maximum peak-to-peak voltage?

Related by 120 degree differences phase to neutral;, 208 V in standard services.

Snip

And I am even less impressed than Fred Abase. You are outside your range of
competence. I am an electrical engineer, but you don't see me pontificating

I have done construction inspection also, including smallish services like
120/240 V 3-phase 400 A. I have also reviewed designs up to 10 MVA at 12 kV.

Michael A. Terrell
Guest

Thu Mar 11, 2010 7:24 am

Jim Thompson wrote:
Quote:

On Wed, 10 Mar 2010 08:31:57 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon_at_My-Web-Site.com> wrote:

On Wed, 10 Mar 2010 00:10:01 -0500, "Jon" <jon8338_at_peoplepc.com
wrote:

"Glen Walpert" <nospam_at_null.void> wrote in message
news:4b9586a2\$0\$15780\$c3e8da3_at_news.astraweb.com...
[snip]

If I were him I would be prepared to show them the inspection report for
the legal installation when they show up. Probably he needs to hire an
electrician to do that; he obviously has not read the NEC.

What? Have you deviants flipped your lid? Knowledge is free. But just try
to get your hands on telephone electronics. It's proprietary information.
There are no books on it at the library. All they show is how the keypad
makes beeps. The rest is secret. How do you multiplex 4 dedicated lines
through one wire? What's the code? But knowledge is free, and nobody's
going to get electrocuted with phone line voltage. So what's the problem
when I'd like to know the information on connecting a generator?

I shouldn't have listened to you guys and just built my own knife switch for
10 bucks. It's impossible to make before break and would have worked fine.

I have a couple of electrician buddies. One of them would probably do the
work for me, but why? Disconnect the service, saw the cable, stick the
transfer switch in between and it's done. Then I also have a service
disconnect for future wiring problems.

I live in Harrisonburg, Virginia. Look me up on 7th Street and I'll have my
brass knuckles to serve you teeth lunch.

So you know where North Mountain is? And Franklin, WV (where my
hillbilly relatives live)? I'll send them over to Harrisonburg and
have them talk to the building inspector.

You done gone and deprived a village of an idiot :-)

...Jim Thompson

Elaborating... I mentioned "redneck" relatives before. The relatives
in Franklin, WV, _are_ hillbillys who travel regularly to Harrisonburg
to shop... Franklin is just slightly more than a wide spot in the

The redneck relatives (by marriage) are in Richmond, probably 5 times
further away. He is indeed a redneck, has done hard time for various
felonies, including drug possession. He'd be ideal to have a visit
with the Jon "brass knuckles" idiot :-)

Thanks for the approximate address, nice short street, though I
imagine they can find you exactly from your posting IP. Enjoy!

People PC is owned by Earthlink.

--
Greed is the root of all eBay.

Michael A. Terrell
Guest

Thu Mar 11, 2010 7:25 am

Jon wrote:
Quote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

--
Greed is the root of all eBay.

Jim Thompson
Guest

Thu Mar 11, 2010 5:01 pm

On Thu, 11 Mar 2010 01:25:39 -0500, "Michael A. Terrell"

Quote:

Jon wrote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

Let's see how talkative he is by Monday or Tuesday

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

The only thing bipartisan in this country is hypocrisy

Michael A. Terrell
Guest

Thu Mar 11, 2010 5:13 pm

Jim Thompson wrote:
Quote:

On Thu, 11 Mar 2010 01:25:39 -0500, "Michael A. Terrell"

Jon wrote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

Let's see how talkative he is by Monday or Tuesday

Or if he still has electricity and Internet access?

--
Greed is the root of all eBay.

Jim Thompson
Guest

Thu Mar 11, 2010 5:49 pm

On Thu, 11 Mar 2010 11:13:50 -0500, "Michael A. Terrell"

Quote:

Jim Thompson wrote:

On Thu, 11 Mar 2010 01:25:39 -0500, "Michael A. Terrell"

Jon wrote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

Let's see how talkative he is by Monday or Tuesday :-)

Or if he still has electricity and Internet access?

highlighted, and mailed it to the director. Who knows? Virginia
often votes Democrat, so they may just approve his Rube Goldberg
scheme

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

The only thing bipartisan in this country is hypocrisy

Michael A. Terrell
Guest

Thu Mar 11, 2010 6:34 pm

Jim Thompson wrote:
Quote:

On Thu, 11 Mar 2010 11:13:50 -0500, "Michael A. Terrell"

Jim Thompson wrote:

On Thu, 11 Mar 2010 01:25:39 -0500, "Michael A. Terrell"

Jon wrote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

Let's see how talkative he is by Monday or Tuesday :-)

Or if he still has electricity and Internet access?

highlighted, and mailed it to the director. Who knows? Virginia
often votes Democrat, so they may just approve his Rube Goldberg
scheme

Email it to the local fire chief, so they know not to respond when
the shit hits the fan.

--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'

Michael A. Terrell
Guest

Thu Mar 11, 2010 7:35 pm

mpm wrote:
Quote:

On the bright side, when the shit does hit, at least the fan won't be
spinning!

No, but they might get hurt or killed at a neighbor's house when his
'Rube Goldberg' acts up.

--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'

mpm
Guest

Thu Mar 11, 2010 8:33 pm

On Mar 11, 12:34 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:
Quote:
Jim Thompson wrote:

On Thu, 11 Mar 2010 11:13:50 -0500, "Michael A. Terrell"

Jim Thompson wrote:

On Thu, 11 Mar 2010 01:25:39 -0500, "Michael A. Terrell"

Jon wrote:

What do I know?

What don't I know.

You don't know enough to come in out of the rain.

Let's see how talkative he is by Monday or Tuesday :-)

Or if he still has electricity and Internet access?

highlighted, and mailed it to the director.  Who knows?  Virginia
often votes Democrat, so they may just approve his Rube Goldberg
scheme :-(

Email it to the local fire chief, so they know not to respond when
the shit hits the fan.

--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'- Hide quoted text -

- Show quoted text -

On the bright side, when the shit does hit, at least the fan won't be
spinning! :)

-mpm

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