why in the world ? would you want a neutral on a 220 circuit / load
it's 220 because it comes from both windings, there is NO neutral in any motor or device using 220vac
the device may be grounded and bonded which would be connected to a neutral on a RESidential power circuit from the power utility but only because the neutral was bonded to ground not because the device needs a neutral wire: BUT NOT on a portable generator
You are 100% right for 220 motors and resistive heating elements. But, some appliances do require both 120 volts and 220 volts and thus the neutral wire must be present. Now, I realize we are not going to be powering the following from a 3,000 watt generator, but a residential dryer is one example. The motor is 120 volts as are the timers. But the heating element is 240. An electric range is another. The clock, lights and sometimes surface burners and timers are 120. Heating elements in the oven are 240.
In the case of my ELM3000, which did not provide a neutral on the 220 outlet (I had to add it), it would NOT have properly powered my residential SEP (Service Entrance Panel) thru my transfer switch and subpanel. Yes, my well pump would have worked, but my 120 outlets would not have worked without the neutral from the generator with straight 220 AC.
The duplex outlets in my kitchen (small appliance branch circuits) are wired in split configuration. The tab between the two sections of the duplex outlet is broken out. These outlets are fed by bridged 220 breakers in my SEP. An open neutral, or nonexistent one in these circuits, would create a very dangers condition for both the appliance and the user. Many kitchens in homes from the 70's and 80's before the NEC required GFCI or shock detectors on SABCs are wired in this manner.
A guy with a RV that has a 50 amp connection would need the neutral if he wanted to feed both legs of his 50 amp cord from each of the coils in the generator (rather than bridging them with a 50/30 amp adapter and feeding 120 only). Without a neutral connection to the generator, either a dangerous or non-working situation - or both - will occur.
The key word is "portable generator". But, I strongly suspect many users will try to set them up so that they can provide power by backfeeding thru something like a dryer outlet to a residetial SEP, a practice I know is all too common in my area (but also potentially dangerous). In these situations, you gotta have a neutral, and the generator frame should be bonded to ground as the neutral is not at ground potential as manufactured.
Note: NEC codes do not legally allow backfeeding a SEP with a portable generator through something like a dryer outlet without a transfer switch. Doing this with the main breaker on will also backfeed power to the utility lines and could seriously hurt or kill folks working on the power lines. Sometimes well intentioned folks who backfeed forget to turn off the main breaker - a transfer switch is a failsafe device to prevent this "forgetfulness".
Professor Randy T. Agee & Nancy Agee. Also Oscar, the totally ruined Dachshund.
2009 Cedar Creek 5th Wheel - 2004 Volvo VNL670 class 8 MotorHome conversion as toter.
Turbocharged, 12L, 465 HP and 1,800 ft. Lbs. of torque.
