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Re: logistics of running a "real high power" coil

Original poster: Greg Leyh <lod@xxxxxxxxxxx>

I'm assuming that your friends' farm has standard single-phase service, and no industrial three-phase. First off, you can probably do most of your prototype development off the existing farm power. Existing grid is always a win over local generation, even if it requires some amount of feeder installation.

If you're planning to need >20kVA infrequently [say only 1-2 times a year] then renting a 50-80kVA construction generator is probably the easiest route; construction-grade regulation is more than sufficient for TC work, and runs about $200-300 for a full weekend. A 50kW construction-grade rig can be towed from the rental yard using a light-duty truck, as well.

If you're planning on needing >20kVA more often, say once a month, then the best bet would probably be to scrounge around for a suitable *diesel* generator. Perhaps your friend with the farm needs one as a backup gen for irrigation, lights, etc? Such an item would be a valid business expense for a farm.

Other than that, my favorite development spots would be industrial warehouse parks, which have copious amounts of free space, three-phase, and are largely abandoned on the weekends. The best spot by far I've come across is the abandoned naval shipyard at Hunter's Point, where we developed Electrum. Megawatts of idle 208V/480V three-phase.

Another critical logistic is rigging and handling. Over 20kVA you'll need a forklift to stage components, erect coilforms and unload heavy items from trucks. Work is still possible [although nasty, brutish and slow] without a forklift, by using liftgate trucks, pallet jacks and overhead chain hoists.

Insurance would depend on what your host requires. If I owned a farm and had a few folks whom I knew well over to work on coils occasionally, I wouldn't even bother. However if you start having frequent unknown visitors from the public, you'd have to consider it.


Original poster: "Jim Lux" <jimlux@xxxxxxxxxxxxx>

Just as a gedanken (I'm not likely to actually do anything with this in the
immediate future), what are the logistics of running a >20 kVA coil.
one rent a generator?  (if so, what kind?) What's the implications of
hooking up to the local utility on a temporary basis?

I'm quite familiar with mechanics of hooking up 100 kVA plus loads in a
stage or movie set context, even on location, but what if you're a private
person wanting to experiment, without all the trappings of a production

What sorts of costs (ballpark) are we talking about?
What sort of insurance is going to be required, and by who?

(Aside from the actual physical facility... assume that I've got a place to
experiment, and I just need that 100 kW of juice...)

Here's a scenario to frame the discussion.  You live in a house (or
apartment) where you have room to build things, but neighbors, homeowner's
association, etc., will get a bit "excited" if you try to fire up the coil.
(besides, that 200A service is only 40 odd  kVA).  However, there's a farmer
with many tens of acres a couple miles away who's willing to let you run

I've been thinking in terms of a trailer mounted coil (because you could
store it at an RV storage place, for instance).

Sure, one might think the best scheme is to buy a (surplus) 200 kVA
generator, but that's not cheap either.