Question on generator hookup to house.

Discussion in 'General Survival and Preparedness' started by Bandit99, Jan 15, 2020.


  1. Bandit99

    Bandit99 Monkey+++ Site Supporter+

    So, I wired up a 240V, 30 amp generator inlet and breaker to my house. Yes, it has two main breakers (one on house and one main feed to property) to ensure no back feed of power onto the utility. I will install a transfer switch this coming Spring.

    I got a 8000 watts Champion generator yesterday plus a cable to go from the inlet to the generator.

    I got reading about how most portable generators have 'Bonded Neutrals' and one should removed it, let it float if you are connecting to a house.

    I asked an old electrician about it and simply said, "Don't worry about it" which of course made me worry. LOL!

    Here is what it says in my manual:
    "The generator system ground connects the frame to the ground terminals on the power panel. The system ground is connected to the AC neutral wire."

    So, this tells me the generator is indeed has a bonded neutral.

    Question: Many of you have generators hooked to your homes and wondering if you had to undo the generator neutral so there wasn't a problem from having two neutral paths or did you simply plug it in not worry about it?
    note: I also read/heard using a bonded neutral generator will cause one's GCFI outlets to trip.
     
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  2. ghrit

    ghrit Bad company Administrator Founding Member

    Mine is a plug in and forget. It's a portable, not permanent installation, which may make a difference. No gfci trips at all, so far.

    The "system" ground on portable machines is to the frame that carries the genset, has nothing to do with the house system.

    Now I'll shut up and let someone that knows something help a bit.
     
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  3. Bandit99

    Bandit99 Monkey+++ Site Supporter+

    That is exactly the type of installation I have. What kind of portable generator do you have? I can look it up and see if it has a bonded neutral. My guess is it does but not all of them do. Please give make and model...
     
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  4. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    The NEC says that you should ONLY have ONE Neutral to Ground Bond in any ONE System.... Likely you should look at the Genset wiring and see if you can find where they did that on the Genset... What I do is replace that link with a Toggle Switch, so I can use the Genset as a Portable and have the Neutral Bond in the Genset, OR open that link for when it is powering the house, as a "Separately derived Source".... It is NOT absolutely necessary to make such a change, as the likelihood of having two links only separated by 10 or 15 Feet of wire will not cause you a Ground Loop Issue, is very small.
     
  5. Cruisin Sloth

    Cruisin Sloth Special & Slow

    If you buy a new stove or dryer in 220 VAC all now have the ground and neutral bonded .
    As the gent said I asked an old electrician about it and simply said, "Don't worry about it"

    What I have done is put a 220VAC NEON bulb in red on the power feed (pull meter to make it dead , that way when the power is back on , you can see the bulb is lit. Always hit main breaker first to OFF , then recheck just before you plug in your dead-man cable link.

    Sloth
     
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  6. Bandit99

    Bandit99 Monkey+++ Site Supporter+

    That is a hell'va idea! I will put that on my 'Do List' for this Spring or, if it ever stops snowing and I get 2 minutes then I will do it now. I will probably just remove the wire for now but first I want to test it and see if indeed will trip the GFCI outlets as I've been asking around and almost no one even thinks to do this and they don't have problems.

    Thanks all!
     
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  7. ghrit

    ghrit Bad company Administrator Founding Member

    Cheap 5KW Craftsman from before Sears went off into the cosmos. The service is strictly backup for short term power outages, it's done well for a 16 hour outage a few years ago. As a full time, off grid machine, it would be NFG.
     
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  8. Cruisin Sloth

    Cruisin Sloth Special & Slow

    I would not fool with the GEN SET bonding , we bond in the Circuit breaker box and in other secondary feed Breaker boxes also (as long as it has it's own grounding outside or internal ground rods )), then as I said above , all newer 2016-18 regs have had internal ground-bonding with all 220Vac units. .
    With gen set off , or dryer / stove unplugged , use an Ohm meter between the Neutral and ground , if it reads OL its not ground-bonded ,if it reads 0.00 then it's ground-bonded. Like my welders , gensets here 3 of them .

    Biggest thing is back feeding to grid or grid coming alive when your genset is on fire and melting. open master breaker first , always
    S
     
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  9. oil pan 4

    oil pan 4 Monkey+++

    You have a neutral to frame bond some where, just have to find it.
    Mine is on a switch.
    On bonds the neutral to ground for stand alone, off breaks it for building tie in use.
     
    Last edited: Jan 16, 2020
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  10. BenP

    BenP Monkey++

    I drive ground rods and ground everything just for good measure; solar panels, generators, antennas, breaker boxes.
     
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  11. john316

    john316 Monkey+++

    stoves.....dryers....as they come in the box.....have the shell,cabinet, bonded to the neutral for a 3 wire hookup.
    if you lose the neutral connection.....then the cabinet becomes "HOT" and can shock you.

    THIS 3 wire system WAS a "TEMPORARY" RULE started in 1941 or 42 to save copper for the war.
    BEFORE this you had 4 wires????
    OVER THE YEARS...what ..how...when to ground...bond....changes EVERY CODE.
    (ground and bond is NOT the same)
    ANYWAY, BACK TO THE TALE.......around 1962,1964. the NEC STARTED 3 wire grounded outlets.....( your plug in 15 and 20 amp 110 volt outlets)
    the neutral and ground were BONDED at the first panel in the house
    AND the neutral was bonded to the panel cabinet AND the metal cold water pipe
    AND along came plastic pipe
    so we started a driven 8 foot ground rod bonded to the neutral( first we used any pipe and it rusted out,
    then we went to galvanized rods, they last a long time BUT they still RUST OUT....THEY are still LEGAL ..
    BUT SOME WANTED BETTER
    SO NOW THE best is a copper plated ground rod
    WE also found that 8 foot rod in dry sand IS USELESS.............
    SO NOW ....the code requires 2 rods over 8 feet apart......................still useless in dry sand, BUT LEGAL.
    (the code DOES HAVE specs on how good a ground must be............BUT, very few people have a tool to check,..
    the tool cost almost $900.00 in 2012 or so when our power company bought one.....

    WHOLE HOUSE surge protectors were just starting up....2004 or so
    2006 or 8 the power company offered a meter with a built in surge protector
    GREAT.................BUT..........A SURGE PROTECTOR..........WILL NOT WORK WITHOUT A VERY GOOD GROUND
    ------WHEN THEY DID NOT WORK....THE smart people got the power company to pay damages......
    SO .........the power company meter shop bought the tool to check the grounds on the house before they would install the meter with the built in surge protector
    MOST EVERY DRIVEN GROUND WAS NO GOOD.........
    A LONG (50-80) feet METAL cold water pipe might pass the test....might not
    NEW HOUSES have had plastic pipe since the 1970's or so....

    SO ...the customer would have to install a good ground rod
    I FOUND A ROD DRIVEN 30 FEET WOULD WORK..............BUT not in every case
    the ground rod had to reach ground water or clay
    after failing a test..........i started driving the rod as far as i could with a hand held impact tool......
    20 to 40 feet..............one job took all 50 feet of rod i had easy but it passed the test

    (when i worked on the computer building on the UF CAMPUS we drove 8 3/4 copper plated rods around the building
    until out truck mounted driver could not move them..........80 to 130 feet....all bonded with 2/0 copper wire to all panels in the building)
    OK...BACK to the stove
    some where around 1980 or so ......20 years after grounding outlets...we decided stoves and dryers should be grounded.................but not for everybody..........just special (dumb) people........people who lived in house trailers,....mobile homes. so mobile homes came with 4 wire outlets for stoves and dryers

    FOR A 4 WIRE , 220 system, you would CUT (remove) the jumper from the neutral to the cabinet(green screw)
    INSTALL a 4 wire cord..connecting the green wire to the green screw on the cabinet.....the white wire to the lug with the stoves (dryer) white wire.......the black and red wires connect to the black and red lugs

    BUT, in the 1980,s and 1990,s.........when you brought you new stove (dryer) home, TO A HOUSE, you would find you had a 3 wire outlet...........you would buy a 3 wire cord.....hook it up and leave the jumper alone .

    SO..........sometime in the late 90,s.....1999 OR SO......we decided..........WTF.............lets drop the TEMPORARY EXCEPTION OF 1942.........and we went back to a 4 wire stove and dryer hookup...........
    SO NOW....JAN 16,2020...........we have millions of houses with 2 wire outlets and 3 wire stoves and dryers outlets.

    SO, TO RECAP, for stoves and dryers, if you have a 3 wire outlet........you use a 3 wire cord and leave the jumper in place.........OR BETTER ....replace the 3 wire circuit with a 4 wire circuit from the panel and use a 4 wire cord as above.
    IF you have a 4 wire outlet.install a 4 wire cord as above

    MANY STOVE AND DRYER DELIVERY PEOPLE INSTALL THE CORDS.
    MANY.............................................................DO NOT KNOW WTF THEY ARE DOING

    BACK TO THE generator..........i would also say "don,t worry about it"..........
    10 feet ..........is "common"............your house ground may not be any good any way.stay out of the rain.water and power is bad.

    BACK TO THE GFI outlet, IT does not know where the system is grounded............does not care.........DOES NOT EVEN NEED A GROUND TO WORK................YOU NEED A GOOD GROUND FOR YOUR PLUG IN SURGE PROTECTOR TO WORK..........and without a good ground it is useless.............
    MOST of the new GOOD ones will tell you if they have a ground.
     
    Last edited: Jan 16, 2020
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  12. john316

    john316 Monkey+++

    Bandit99................did you see the last bit re. generators and GFI,s
     
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  13. oil pan 4

    oil pan 4 Monkey+++

    3 wire worked for 50 years. That's what I use.
    But I do pull 3 insulated conductors with bare ground to the boxes when installing a new outdated 3 prong receptacle.
    Unless I'm using it as a welding circuit.
     
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  14. arleigh

    arleigh Goophy monkey

    The earth is not the same everywhere you go.
    Years ago the phone company was establishing a site and the earth had too much quartz in their area requiring a large vault underground and ground rods driven through like a porcupine to absorb enough ground to work.
    Measuring ground conductivity might be required one area to the next.
    Personally, I do not tie into house wiring I have independent wiring, both grid 110/220 AC and 6/12 VDC and 110/220 6500 watt AC gen. Each have their own ground.
     
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  15. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    "Ground is NOT Ground, the World around" Old saying used by Many Electricians and Radiomen.... Here where I live we are basically sitting on Glacier Till, or Bedrock, one of the two... This equates to sitting on a Piece of Glass, Ground Wise, and RF Ground... We had to build a Uffer-Ground for our 3MW PowerHouse when we in built it....
     
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  16. Bandit99

    Bandit99 Monkey+++ Site Supporter+

    John316, Yep! I will try it without doing any modifications this weekend... Thanks for taking the time to write it up!
     
  17. offgrittyt

    offgrittyt You gonna eat that?

    THE ONLY THING you need to worry about is getting a transfer switch installed. Backfeeding voltage on to the grid is deadly to the utility workers and anyone else downstream from the high voltage you are creating by backfeeding your transformer. It doesn't matter how many manual main disconnects that you have, human error can happen if someone forgets or doesn't know.
    As far as fiddling around with neutral on your generator, don't worry about it, but it's not a bad idea to connect a ground wire to the ground connection point on the genny.
     
  18. mysterymet

    mysterymet Monkey+++

    I have a generac with a transfer switch that comes on automatically when we lose power. Best money I spent when buying my current house.
     
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  19. Cruisin Sloth

    Cruisin Sloth Special & Slow

    Same here Ms Mmet .
    I use it in full mode when Im not around for SO .
    Other than that , I can run full farm on a 3500 w inverter unit. Quite and uses 1/2 gal for 7 /8 hrs as I have measured. My APU is 3600rpm screamer , but SO is at ease with it.
    Sloth
     
    Last edited: Feb 16, 2020
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  20. ghrit

    ghrit Bad company Administrator Founding Member

    My transfer switch is a manually operated interlock.
    One thing that cannot be overemphasized is the need to keep the incoming wires cold while on your gennie. If you have to, pull the meter. The powco won't be happy, but they will come out and restore the seal. Expect a bill for a service call.
     
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