Hope someone can answer a basic question for me on the attached wiring diagram from a 5 or 6 y/o Nikota 3500/3000w generator.
The genset runs well, producing 240v at the NEMA L14-30 receptacle and 120v at the duplex receptacle. A 4P2T toggle switch selects the voltage between 240 and 120. The wiring to the L14-30 receptacle seems straight forward, with the brown feed from the first phase (call it Phase 1) providing 120v on one terminal, and the blue wire from the other phase (Phase 2) feeding 120v to the opposite terminal. Since the feeds are 180 degrees out of phase, 240v is the result across those terminals. A few years ago, I added a neutral where there originally was none so I also have 120v from the L14-30 receptacle when needed, but that's the only mod that's been done.
So far so good. What has puzzled me is the way the 120v circuit is wired. As shown on the attached diagram, when the 4P2T is switched to 120v, the brown feed from Phase 1 connects to the hot side of the duplex receptacle, yet the blue feed from Phase 2 connects to the neutral side, on the opposite side of the receptacle. Surprising to me is that the jumper plates are fully intact on both sides of the receptacle. Question: Why doesnt this yield 240v across the terminals of the duplex, just as it does with the L14-30 when the selector switch is set to 240v? And, even more basically, why doesnt a ground fault occur due to the blue feed being connected directly to the neutral side of the duplex receptacle by virtue of the intact jumper plate?
It's been suggested to me that the 4P2T switch may be moving the windings from series for the 240v to parallel for the 120v. Does that sound right? I'm not seeing how that's being accomplished by the switch, nor for that matter, how the windings are in series when in the 240v mode.
The genset runs well, producing 240v at the NEMA L14-30 receptacle and 120v at the duplex receptacle. A 4P2T toggle switch selects the voltage between 240 and 120. The wiring to the L14-30 receptacle seems straight forward, with the brown feed from the first phase (call it Phase 1) providing 120v on one terminal, and the blue wire from the other phase (Phase 2) feeding 120v to the opposite terminal. Since the feeds are 180 degrees out of phase, 240v is the result across those terminals. A few years ago, I added a neutral where there originally was none so I also have 120v from the L14-30 receptacle when needed, but that's the only mod that's been done.
So far so good. What has puzzled me is the way the 120v circuit is wired. As shown on the attached diagram, when the 4P2T is switched to 120v, the brown feed from Phase 1 connects to the hot side of the duplex receptacle, yet the blue feed from Phase 2 connects to the neutral side, on the opposite side of the receptacle. Surprising to me is that the jumper plates are fully intact on both sides of the receptacle. Question: Why doesnt this yield 240v across the terminals of the duplex, just as it does with the L14-30 when the selector switch is set to 240v? And, even more basically, why doesnt a ground fault occur due to the blue feed being connected directly to the neutral side of the duplex receptacle by virtue of the intact jumper plate?
It's been suggested to me that the 4P2T switch may be moving the windings from series for the 240v to parallel for the 120v. Does that sound right? I'm not seeing how that's being accomplished by the switch, nor for that matter, how the windings are in series when in the 240v mode.
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