floating neutral generator.

bevans6 · July 03, 2009, 02:27:41 PM

My previous generator had a bonded neutral, my new Yamaha EF3000ISEB (which works wonderfully, is very quiet and starts the AC effortlessly) has a floating neutral. I wonder if I should bond neutral to ground in it, or if there is some reason why it should stay floating. My test plug inside the coach shows open ground when running off the generator, which does seem odd. Any ideas? The generator is plugged into the coach with a 120 volt RV cord with a twist-lock adaptor. There is connectivity between the grounds all the way through the cord. all I can think of is the little test plug light is showing no connection between neutral and ground, not truly open ground. Of course, all the generator is actually grounded to is the chassis of the bus, which itself isn't grounded to anything.

thanks, Brian

Jerry Liebler · July 03, 2009, 03:29:20 PM

You should bond the neutral to ground inside the generator.
Regards
Jerry 4107 1120

bevans6 · July 04, 2009, 04:22:36 AM

That is my feeling as well, but I am a little shy about voiding the warranty. I'm not sure why they would make it a floating neutral in the first place, there must be a reason why this one is floating vs the previous Yamaha 6600DEX which was bonded. My thinking is that I can very easily bond the neutral inside the twist-lock plug that terminates the feed to the bus at the generator, that is physically and electrically virtually identical to opening up the gennie and bonding on the back side of the twist lock receptacle. That leaves it floating for use when the bus isn't plugged in. Again, not sure why Yamaha wanted it to be floating in the first place.

thanks, Brian

Len Silva · July 04, 2009, 06:47:26 AM

Many reconnectable generators do not have the neutral bonded, leaving it up to the user. There should be information from the manufacturer as to how to proceed. I don't see why bonding at the receptacle would be a problem.

Jerry Liebler · July 04, 2009, 07:12:15 AM

CAUTION!!!
Bonding must be done on the generator side of the plug! Doing otherwise, as Brian seems to suggest, will result in a DOUBLE bond when the coach is plugged into shore power Proper bonding should NOT affect waranty, check your generator's owners manual for instructions on how to implement the CODE REQUIRED bond.
Regards
Jerry 4107 1120

Len Silva · July 04, 2009, 07:57:04 AM

Yes, definitely. The closer to the generator, the better. I should have been more clear, though to me, receptacle is on the generator side and plug is on the coach side.

bevans6 · July 04, 2009, 09:05:40 AM

the plan is to bond neutral inside the twist-lock plug that is directly attached to the generator. The twist-lock is a dedicated pigtail solely for plugging in the bus. I will label it neutral bonded. That neutral will be the only bond in the system. All this only after I talk to the manufacturers tech line, if one exists, and ask if I can open the gennie and bond neutral inside it. Another idea that would work is to make a bonding plug to plug into one of the 15/20 amp outlets. Neutral and ground are not switched by the breaker, so that would work as well, and be obvious and reversible.

No one has come up with a good reason why neutral wasn't bonded in this generator from the factory. I found out my Honda EU2000 is probably the same, and so are a lot of small generators. The only reason I can think of is for when someone uses it to power up a house that has a bonded main panel. But that's by no means the common use for a small generator.

In other news, I successfully realigned the dual opening doors so they meet in the middle, are the same height, meet the seal at the bottom and I only had to use the heat wrench on one of the rod-ends, and I only twisted off one of the 5/16" bolts that hold the bracket to the door. 90% successful in my book, and now I need to find a new seal kit for around the door. I also discovered that I need to replace or rebuild the front door cylinder, it leaks like a sieve when it's pressurized and open. I also made an extension arm from 1" billet aluminium to allow the curb side mirror to peek out around the open door, so that I can see more on the curb side than the front of the windshield surround. The front door half would hit the mirror arm when open, and the mirror couldn't be adjusted out far enough.

Brian