Fair enough. Some of my motors are 4 - 5 kW, and those power levels are rather inefficient on single-phase.
Cheers
Standard 240VAC outlets in the US are generally rated for 40 Amps continuous,
BLIMEY!
I wonder what the house wiring (behind the outlet) looks like !@#$%
Australian Standards limit a normal 240 VAC outlet to 10 A, with provision for an enhanced socket rated at 15 A. Beyond that we go to 3-phase for efficiency. I would worry about motor inefficiency at 40 A.
The 40 A business explains a few things, like the rather large 3-phase convertors American people keeping talking about. We could not run those here in Oz.
multiple electron microscopes.
I assume this is humour? I built a scanning electron microscope once, for a thesis, and helped build a 1MeV electron microscope too.
Cheers
Roger (PhD)
welding machine, electric cooking stove etc, I dont think a 240 volt ten amp service would handle that??
240 volt 3 phase in a residential setting just doesnt happen here that I am aware of......
mike sr
You may be misunderstanding me here. What I said was that a standard wall socket, or General Purpose Outlet (GPO) here in Oz, is rated at 10 A max. The feed into the house will of course be at a significantly higher rating. Even so, the wring code assumes that most houses will not be running too many 10 A devices all at once.
So yes, portable welders have to either stay within the 10 A rating or have a special 15 A plug (needing a 15 A socket). Or go 3-phase.
Electric stoves may draw 7 - 10 A per hot plate. They are NOT plugged into a socket: they are hard-wired to the switchboard with their own fuses. Equally, our 4.8 kW (20 A) off-peak water heater (part of a solar panel system) is direct-wired to the off-peak meter on the switchboard. The average homeowner does not get to play with such devices (well, should not).
Very often a residential house in Oz may only get a single phase supply, with the supply authority distributing the houses down a street across all 3 phases for balance. However, we live on a farm and do have 3-phase. OK, the supply authority *****ed at the start when I said I wanted 3-phase at 60 A per phase, but were convinced (or at least stopped *****ing) when I pointed out that we would be running a fair bit of 3-phase machinery. Maybe my anticipated demands were a bit 'generous', but better to have over-capacity than not enough.
Cheers
Roger
standard wall outlets here are 120 volt 15 & 20 amp ratings, 14 & 12 gage copper wiring respectively
electric clothes dryers, electric stoves, air conditioner, larger compressors etc are usually 240 volt single phase and use a 20 or 30 amp rated receptacle
My drops for the machines are 20 amp 250 volt rated
mike sr
Not if you actually looked. We live in the city and the house is surrounded by 100+ foot fir trees which occasionally dropped a branch *through* the roof. I fixed that problem by getting an industrial strength (8X stronger than the standard residential version) standing seam roof installed. No more roof leaks but a solar array would not last even a single year with the bombardment. We don't want to lose the trees either.
#6 gage wiring is common for those currents. These outlets are not everywhere throughout the houses here, mostly things like electric dryers, electric ovens, and in my case a few other uses including a "bedroom" that is actually my metal shop and the lower floor basement.
No, I have an ETEC Autoscan SEM and a Zeiss S9A TEM, along with multiple research optical microscopes. The TEM can resolve individual iron atoms. I don't have a photo of the TEM so I included a photo of something quite similar. These are not all that I have.multiple electron microscopes.
I assume this is humour?
Lab optical microscopes I still have, nothing bigger. I am, after all, retired now!
Out of curiosity, what do you use the SEM and TEM for?
Cheers
Roger
I am also retired, I bought these EM's surplus for fun and my total expenses in both EM's is about $1,600 US. The SEM needs some work though and it's original purchase price was over $125K US; I have the original purchase sheet and all of the history for that particular machine. The Zeiss TEM came from a hospital. The SR71/U2 stereo pair photo examination microscope was purchased surplus new (still in the original box!) at an auction for a ridiculously low price because no one else there knew what the heck it was. The Reichert large research microscope was surplus (the lamp was burned out so the price was low) and I have 5 large Reichert boxes of accessories for it, including dozens of objectives, perhaps a dozen eyepieces. XY stages, a group viewing head. Also full episcopic, diascopic, differential interference contrast, phase contrast, light and dark-field, and polarization capability (including an elaborate Zeiss polarization analyzer with their color chart) in essentially every useful combination. We plan on taking a trip to down under sometime, since we have never been there so please feel free to contact me via private email.
I see.
Doesn't half scream WASTE by hospitals and others, where the staff have no involvement. Sad.
I do have some good microscopes - also left over from a closed Government organisation. They get used occasionaly. What I lack is floor space! It seems to be taken up by machinery ...
Cheers
Roger
I'm afraid that the acquisition of the hospital TEM was *way* more complicated than simply "waste". It was actually owned by one of the physicians working there. The hospital administrator who was retiring soon decided to make a grand exit by a major building remodeling before leaving. As a result the TEM owner was given one week to remove his personal TEM from the premises so that the remodeling could commence. He had no place to store it in the meantime since he lived in an apartment. My cost was peanuts and renting a lift-gate truck.
That is not 'sad', it is utterly pathetic. Ego-driven destruction of assets.
Cheers
Roger