Connecting Neutral & Ground from Generator to Home

[ePowerBank]

Worse than just having 240vac, any 120vac loads will have floating neutral so the 120vac house outlets will have varying voltage depending on how much 120vac loads are on each side of L1, L2 to neutral. Very unsafe and hazardous to 120 vac appliances plugged in. Very bad design! Shows total lack of understanding of U.S. split phase system. So can you believe the cord #2 plugged into one generator L14-30 outlet to house service entry is correct ???

Understood, and a concern I tried to address by installing meters - below from a couple weeks back was at the 2 generator HOT legs entering MAIN. Does this cancel your concern (I HOPE) for varying voltage?

I think part of your comment is at heart of my issue (concern) - "how to apply Neutral in this case". I wonder if it's something similar to installing High Frequency Inverters? How 240v is split when coming into homes from a transformer isn't same, and maybe source of this problem? My mind is parked on idea that AC needs to return or cycle back to source (the generators or home panel?).

YES, the L14-30 at the generator control panel works (how below readout was connected - so maybe I stop there and full-load test (I was successful in partial load testing the micro and HVAC fan).

NO, I wasn't successful testing Cord #1 (NEMA 10-50) and fried 2 power strips.

 

[RCinFLA]

Replace 10-50 with 14-50 socket.

Connect L1, L2, and ground as was with 10-50 socket.

Remove white neutral wire splice and connect them together on neutral of 14-50 socket.

 

[ePowerBank]

Replace 10-50 with 14-50 socket.

Connect L1, L2, and ground as was with 10-50 socket.

Remove white neutral wire splice and connect them together on neutral of 14-50 socket.

I like that - what was suggested a long time ago, but I was too cheap to save the terrible $40 piece junk.

I know that the L14-30 works (in parallel mode), which includes a neutral.
I know the banana lead on generator control panel has continuity to generator neutral.

As you say, it seems I'm just upgrading the cheap (30A) plug for a 50A plug ;--(

Either I'm going to make a new box, or buy another parallel kit, that maybe includes a circuit breaker, or better yet, a breaker ON/OFF switch.
So much for the cheaper solution - you gets what yous pays for.

 

[ePowerBank]

Well if at first you don't succeed, go to DIY Solar Power Forum for input you want to hear, and maybe even input you don't want to hear.

After plenty of research (and input) I came to conclusion the parallel kit sold with my generator was junk with old NEMA 10-50, so I replaced with NEMA 14-50.

Successfully tested my homemade parallel box with the new 14-50 today, ran microwave, sump pump as well as lights etc. Further load tests to follow, i.e. furnace etc.

Don't like the cheap volt / amp meters I went with and wouldn't recommend as the display is hardly visible. I tried putting copper tape on one but still bad.

THANKS ALL FOR YOUR CONTRIBUTIONS !

 

[Tecnodave]

I like your solution, when I first saw that original wiring I stumped as to how that could possibly work, It is way not code to float the neutral, no way could that be legal as to the NEC, It was a compromise to use the non safe 10-50 connector that is used in an R.V.

Stoves and dryers used to be NEMA 10-50 connector and that is OK if all the loads are 240 volt only but most modern stoves and dryers use 120 volts for the controller and most electric stoves have a 120 volt outlet therefore are not 240 volt devices but are 120/240 volt split phase devices so the standard for newer appliances require the use of the NEMA 14-50 connector.

If my R.V. were 120/240 volt I would definutely change the cord and connector to the NEMA 14-50 connector.

In any and all instances the neutral and ground should be bonded at one place and one place only. In the situation of the R.V. connected to shore power that neutral bond belongs in the main power panel but when the R.V. is on its own making its AC power from the inverter or generator on the R.V. Some form of ground bond switching is required here. Most high quality Inverter/chargers meant for this use do indeed have a “ground bond switching relay” My MagnaSine does and the Samlex EVO also uses the ground bond relay so when you connect to shore power (charger mode) the inverter opens the neutral/ground bond locally but when in invert mode the neutral/ground bond is done by the inverter.

One problem poorly diagnosed is the EMI/RFI filter found on all switch mode devices which filter off the EMI/RFI from the hot and neutral conductors and shunt that current back through the ground wire. If there are unequal noise currents on the live wire and the neutral wire this will cause the GFCI to trip as the hot wire and the ground wire must be within 3 ma. of each other. The GFCI devices meter only the live and neutral wires, not the ground wire. So if there are 10 ma. of noise on the hot wire but not on the neutral the GFCI will see this as a ground fault and trip. I have seen freezers on a concrete floor in a garage where they could not be protected by a “personnel” GFCI which trips at 3 ma. The solution is to use an “appliance” GFCI which trips at 30 ma. These are not available as an outlet but are a dead front device (no outlet but input and output wires which are hard wired) which is wired in series with the outlet, It is the same form factor as a normal outlet so an “appliance” GFCI can be mounted in a double box with a NEMA 5-15 or 5-20 outlet to provide that protection. This is commonly done with hydronic zone heating systems to provide GFCI protection on the concrete floor that the furnace is mounted on. This would also be legal on a generator as it is an “appliance”

 

[ePowerBank]

My MagnaSine does and the Samlex EVO also uses the ground bond relay so when you connect to shore power (charger mode) the inverter opens the neutral/ground bond locally but when in invert mode the neutral/ground bond is done by the inverter.

@Tecnodave Thank you for your reply - I'm guessing this is something many of us have in common (no joke lol).

Just curious, what type of application you have the MagnaSine in?

 

[Tecnodave]

I have a small house out of town with very unreliable power company feed in the Santa Cruz mountains. Im totally set up as off grid but i do have a power feed from the power company, its not reliable and is 120 volt only 30 amps. I have two banks of flooded lead acid @426 a.h. each charged by two MidNite Classic 150 charge controllers so even in nasty weather I have enough power from solar alone. Due to government regulations the whole solar array is mounted on non buildings so the building inspector has no say. Im totally code compliant but the main is mounted on a large old motorhome, panels,controllers, the works. I run power to the house via a flexible cable so it’s not hard wired. Its not a building so the building department has no say anyway it is a state registered vehicle so the county has no say....

The whole system is bonded together with only one ground connection at the main panel of the house ground rods at the motorhome location bonded back to main ground rod at power company meter location.

My other is a cabin in Alaska out of town as well, 1,200 watts small inverter...real basic but a luxury in Alaska MidNite charge controllers and Cotek inverter. I do not stay there when the weather gets serious.