3000W Chinese Gensets Info.

Old & Slow wrote:
Men of great learning,

I think im making progress then, bingo, the fog again. Maybe I can KISS. I look in my house panel box and the white wire is bonded to earth ground. Ok. now folks like MrWiz, who are power generating pros put in protection by adding a third wire. So we can complete a circuit with one hot wire (black)and one, and this is were my brain gets scrambled. I can complete a circuit with one hot wire and mother earth. Earth ALWAYS a faithful servant. Now this unprotected copper wire is also bonded to earth. So it is to catch some stray source of power, leakage, from some unknown location. I think. Ok Now the RV . My genny has a neutral white for the completion of a circuit. Not bonded to mother earth. I think. Where is there a possible problem with a short circuit or leakage in the RV that would make the frame hot? From this, I think, neutral white wire that MRWIZ, I think, is trying to get me to understand, there is nothing neutral about it. I need a long walk on a short bridge. Anyway I fear my RV frame might in some way become HOT. From my genny. End.

O&S

O&S,
The chances of your frame becoming "hot" from your genset is very rare. There is more of a chance that an appliance in your TT would cause the problem. However with the designs of appliances today, It would be a freak of nature that would cause the problem. My coach was built in 1980 when it was required to bond the neutral of the coach to the frame. When I plugged my genset into the coach with its reverse polarity problem, the neutral was the "hot" wire and pushed voltage to the frame via the bonding jumper. The jumper is now removed to isolate the ground from the neutral. Today the panel in your TT is considered a sub-panel and is not bonded. Only main panels are bonded. Therefor the chances of the frame becoming hot is a very rare problem unless you have a major fault with an appliance in the TT. In that case the chances of the breaker tripping and opening the circuit, would be much greater then the frame becoming hot. I would not worry about it.

I don't know why they call a neutral wire a neutral wire. It actually is a common wire between two phases in the middle. On a transformer the common/neutral wire is grounded, stablizing the circuit. Earth being common with all things makes a good grounding means. That's why it is used. That is also why on the Chinese genset you can only get half of the rated amperage out of the 120 volt recepticals. It is a three wire system with two phases of power. Each phase will give you half of the rated current in 120 volt mode. However on the 240 volt receptical you get full power because you are using both phases at the same time. Each phase on a 3000w genset produces onlt 1500 watts or about 12.5 amps. In the circuit the neutral is what is called a "center tap" or the point where the two phases are hooked together. In a transformer you have two coils on the secondary side. Those coils can be series together to create double the voltage and "center tapped to create a neutral or be hooked in paralell to produce the voltage of a single coil with double the current of a single coil. Thus we have the "RV Switch" featured on some gensets. The RV Switch changes the coil configuration from series to paralell. That is why the 240volt receptical on those gensets will not work when in RV mode. The coils are producing 120 volts of the same phase with double the amprage.

When I finally get a good Chinese genset, I will change the configuration of the coils to paralell and replace the 240volt recepticle with a 30 amp RV recepticle. I will only get 120 volts but that is all I will ever need anyway. But I will have double the current available.