Can I Plug a 5-15 NEMA Plug Into a 14-30 NEMA Receptacle?

The blades are too far apart for the 15 to fit, besides the whole fire hazard thing. A short could easily deliver 75 amps on that size wire, and that 30 amp breaker by UL specs could deliver that load for a full minute before the breaker would trip. That insulation would be completely melted an the cord would be in full flame mode by then.

Consider this: The unlawful killing of a human being without malice aforethought, either express or implied, where there is no intent to kill would be considered involuntary manslaughter. The accuseds responsibility for causing death by committing what might have been a minor criminal act. For example, a person who runs a red light driving a vehicle and hits someone crossing the street could be found to intend or be reckless. Intentionally rewiring that receptacle to make it function improperly could certainly be considered reckless.

Response: If voltage drop is the problem you can use larger wire, but still use a 15 or 20 amp receptacle, and no more than a 20 amp breaker, a larger breaker won't give you more volts. Voltage drop is caused by resistance of the wire, thicker wire has less resistance.

Nema 5-30

So I get it, you want to adapt a dryer receptacle because something you got is tripping a breaker. You got the electron flow right, but Irv is right, it is dangerous, even if he needs new glasses to read the NEMA eye chart.

Receptacle configuration is designed for protection of wire, a NEMA 5-15 cords and equipment connected to it are intended to be protected by no more than a 20 amp breaker, if a 20 amp breaker is tripping you are overloading it beyond a safe level, something is going to burn.

It would be better to describe your problem, and seek the cause or alternatives.

NO. - And why would you want to do that?

If I understand you you want to reconnect a standard plug in a non-standard wire configuration.

1. That's a hazard, as you expose anybody else who comes along and logically assumes

that 'the receptacle is wired properly to danger.

2. Mechanical - The spacing between those two pins should be different.

3. Electrical - The two pins in question would connect 240V. to a 120V line,

and 30 A.240V. to a supposed 15A. 120 V. device.

That receptacle offers a 3 Ph., 4 wire connection. Plugs are cheap.

If you HAVE TO make such a connection, buy a Nema 14-30 plug and select the pins

you wire to. You also get the proper ground.