185EZ wrote:I wanted a generator so I wouldn't have to run my 7000kw in the rv just to charge the batteries and run a few things.Amazing what you can get for $250 these daysI have a Durastar 4400 generator but the hz would vary too much and it would trip error codes on my Progressive EMS and i couldn't just plug it into the rv since it would give a fault code on my inverter.So I bought a dual fuel Sportsmanhttps://www.amazon.com/Sportsman-GEN4000DF-SS-Sandstorm-4000-Generator/dp/B079RBD936http://www.amazon.com/Sportsman-GEN4000DF-SS-Sandstorm-4000-Generator/dp/B079RBD936Works great on propane and the hz only varies from 61 to 62 hzBut the EMS shows an error code of open ground.I even tried grounding the terminal lug into the ground and nothing changedEverything works fine if I bypass the EMSWhat else can I do to fix the open ground?You need to connect the ground pin to the neutral pin using a bonding plug at the generator or bypass your EMS when on generator power. You can probably bond one of the 20A outlets and it will suffice.

You may need to get an inverter genset that puts out true sine wave output. I cannot run my UPS, printer or several other bits of gear on my Champion 3500/4000 dual fuel non-inverter, but it works fine on my Champion 3500/4000 inverter. I doubt grounding it will correct the wave form. But I'm not an electrician or electrical engineer.

wnjj wrote:185EZ wrote:I wanted a generator so I wouldn't have to run my 7000kw in the rv just to charge the batteries and run a few things.Amazing what you can get for $250 these daysI have a Durastar 4400 generator but the hz would vary too much and it would trip error codes on my Progressive EMS and i couldn't just plug it into the rv since it would give a fault code on my inverter.So I bought a dual fuel Sportsmanhttps://www.amazon.com/Sportsman-GEN4000DF-SS-Sandstorm-4000-Generator/dp/B079RBD936http://www.amazon.com/Sportsman-GEN4000DF-SS-Sandstorm-4000-Generator/dp/B079RBD936Works great on propane and the hz only varies from 61 to 62 hzBut the EMS shows an error code of open ground.I even tried grounding the terminal lug into the ground and nothing changedEverything works fine if I bypass the EMSWhat else can I do to fix the open ground?You need to connect the ground pin to the neutral pin using a bonding plug at the generator or bypass your EMS when on generator power. You can probably bond one of the 20A outlets and it will suffice.I know enough to get by but I have no idea what you just said lolI'm fine knowing the EMS is within range and unplugging it to use the generator.Is the open ground anything to really be worried about?I don't want to be connecting pins and bonding things at this time unless it isn't a big deal.appreciate the help.

Yep, you just need a bonding plug. I made my own ($4) to get rid of the E2 code on the EMS. Here's one already made if you don't want to try it yourself.Bonding plug

The "open ground" diagnosis is not correct. It's the most likely guess by the EMS based on what it can discern from the two hot wires plus the safety ground wire. When you're on shore power the open ground diagnosis has a high probability of being correct. When being powered by an unbonded generator, it's an incorrect diagnosis. Shore power has what's called a "neutral-ground bond", where the neutral conductor and ground conductor are connected upstream of the power output. The majority of portable generators do not have this neutral-ground bond, and the EMS wrongly diagnoses it as an open ground. To make the EMS happy you need to add this neutral-ground bond. Many people think the simplest way is to take a standard plug and wire the neutral (wide blade) and ground pins together, then plug it into the same generator outlet that you plug the RV into. There have been pictures posted, but with the forum requiring pictures to be hosted on an outside web site, all the ones I know about are gone. Take a look here for more info: http://noshockzone.org/generator-ground-neutral-bonding/ . To read more, search for "generator bonding plug" and you'll find lots to read, videos, and even pre-made ones to purchase.

Portable Generator open ground | Good Sam Community

wnjj
Explorer II
Oct 08, 2018
Sounds to me like the neutral on the 20A generator receptacle isn’t the same as the neutral on the 30A. One of them must be hot-neutral swapped. Is there continuity between neutral on the 20A and 30A (generator off)?
185EZ
Explorer
Oct 07, 2018
road-runner wrote:
185EZ wrote:
Sorry, didn't think the 50 amp would make a difference with the generator thing.
only one dogbone 30 amp male to 50 amp female
I have a EMS PT50X
I don't have an EMS, but I think there's a very good possibility the EMS will diagnose the dogbone provided power as defective. Somebody with a 50 amp EMS can say this with more certainty. You said the EMS is happy with house current. Is this from a 240 volt outlet? If so, plug into 120 volt shore power using the dogbone and see what the EMS says.

I have 120v 30 amp service at home and the dogbone works fine with the 50 amp EMS.
I have also plugged into a campground 50 amp and EMS works fine.
I let the generator and EMS do it's thing before I plug it into the rv.
Doesn't really make a difference since the EMS won't let power through at this time whether the cord is plugged in or not.
I think the EMS is doing a great job but maybe too good.
Like going to the doctor.
Hey Doc I feel great
Well our tests prove otherwise.:(

Everything was good until the bonding plug
I'll just deal with no EMS and an open ground. Pretend it never happened, lol.
road-runner
Explorer III
Oct 07, 2018
185EZ wrote:
Sorry, didn't think the 50 amp would make a difference with the generator thing.
only one dogbone 30 amp male to 50 amp female
I have a EMS PT50X
I don't have an EMS, but I think there's a very good possibility the EMS will diagnose the dogbone provided power as defective. Somebody with a 50 amp EMS can say this with more certainty. You said the EMS is happy with house current. Is this from a 240 volt outlet? If so, plug into 120 volt shore power using the dogbone and see what the EMS says.
road-runner
Explorer III
Oct 07, 2018
Being a generator that none of the rest of have likely used, there could be something "different" about it. For example, maybe the outlets are miswired, with hot and neutral swapped between the two duplex receptacles. Another possibility, maybe the generator's waveform is sufficiently flawed to be triggering some error in the EMS. Maybe there's a wiring fault in the RV that's not showing up with shore power or the internal generator. One thing that's different with this generator is that the DC output doesn't have its own winding, but rather uses a tap on the main winding. But overall, I don't see anything in the Gen4000DF wiring diagram that looks like an issue. The wiring diagram is on page 30 of the manual at this link: http://www.buffalotools.com/manuals/gen4000df-ssmanual2017_sf.pdf
185EZ
Explorer
Oct 07, 2018
Sorry, didn't think the 50 amp would make a difference with the generator thing.
only one dogbone 30 amp male to 50 amp female
I have a EMS PT50X
enblethen
Nomad
Oct 07, 2018
Now we have a fifty amp rig. Lots of items that can be effecting readings. 120 volt AC water heater elemnet for one.
What combination of adapters are you using to plug rig into the genset? They are a problem in many cases!
185EZ
Explorer
Oct 07, 2018
quick recap
50 amp cord works fine with EMS and house current
onboard 7000kw genset works fine

1st portable generator would have hz vary ALOT, 58 to 98hz, and EMS wouldn't let power through.
Funny thing is when it did let power through there was no open ground fault.
If plugged into rv without EMS it would give a fault code to charger/inverter but power up other appliances and a/c.

Got a 2nd portable generator. 60 to 61hz.
But showed an open ground and wouldn't let power through
Disconnected EMS and all good with the rv

I think I'll leave EMS out before I screw something up
enblethen
Nomad
Oct 07, 2018
You need to back up a little!
First you may read continuity as some devices in the rig will cause this.
Open the 120 volt power distribution panel. Turn off all circuit breakers. Check between the white(neutral) and the green or bare ground wire. You should have continuity from genset cord body with jumper.
Check between the black and the ground. You should not have continuity.

If you do not have as shown, then unplug the rig's shore power cord. verify the cable to insure it is wired correctly. Has some one replaced the rig's cord body? Check it.
185EZ
Explorer
Oct 07, 2018
EMS removed
RV
Generator not running plugged into rv
Bonding plug in
No continuity between neutral and ground in any receptacle in rv.
Only continuity between neutral and hot

Generator
Bonding plug in
Continuity between ground, neutral and hot
Bonding plug out
continuity only between neutral and hot, same as rv
wnjj
Explorer II
Oct 07, 2018
What Drew said.

To further test, turn the generator OFF but leave the RV and the bonding plug connected. If you then go inside the RV, there should be continuity between the ground and neutral of any receptacle. That is what the EMS is looking for. If, for example, your RV shore power cord has them reversed you’ll instead find that hot and ground are shorted.

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