I hate to admit it on here, but I have a generator cable like that. Well, not EXACTLY like that, I at least wired mine up to go from my 240V 20Amp generator to a 240V 30Amp dryer jack with #12 wire. Besides, so long as you disconnect the mains first, it's perfectly safe! I mean, I don't exactly have a kirk key on there but it's not like my family or I make a habit of playing with the main breaker. Not that I'd recommend this to a laymen.... And oh man the lady at the checkout at lowes gave me a "I hope you're not planning on doing what I think you are!" when I roll up to the checkout with a generator, a dryer cord, a handy box and 25' of romex. "It's OK, I'm an engineer!"

Re: risk to linemen, I don't think there is much, if any risk at all of someone not closing the main and energizing the lines- a typical 20 or 30amp generator would trip it's own breaker or stall with just the hot water heater or A/C on the homeowner's own panel, forcing them to shut off every breaker in the house (including the main) but the most critical lights & receptacles before bringing the generator online.

At any rate, it's way safer than the double-ended plug I made from an old interior-grade ungrounded extension cord to plug my shed in because I'm too lazy to dig the conduit and finish wiring it up right (ducks). Don't worry about my shed bursting into flames though, alas, the suicide jumper is no more. Damn thing scared the hell outa me anyway, I don't know what I was thinking... See, now I have a NEMA plug wired directly into the panel so I can just plug in my shed to an extension cord like any normal "small" appliance (ducks again). I hope I'm providing a good professional role model for the vocational students browsing this forum!

[This message has been edited by SteveFehr (edited 12-02-2005).]