I'd go for the 3phase powerline installed to the building by the power company .
cvanc has to come up with a solution in less than 2 weeks
I believe that when the OP said:
I've got maybe 2 weeks to propose a solution so there's a bit of time to kick this around but not a lot.
OP was trying to say that while he needs to
propose a solution in the next week or two, that does not necessarily mean it can be implemented in that timeframe, though I am sure that it will become a "
sooner, rather than later, please" affair shortly after that.
Since the power company hasn't even responded yet, there is a good chance that it could potentially be many months before that could be installed, if it is even within the budget.
If three phase is already in the building, it will be possible and cost-competitive with other proposed solutions, probably in the range of $5000 to add a minimal 3-phase service.
If 3-phase is
not currently in the building, the price instantly becomes tens of thousands of dollars. If it were in a remote location (unlikely), it could be $100,000. Once you get into multi-tens-of-thousands of dollars, it may be more cost effective to change locations than to bring 3-phase power to that building. Without knowing anything about the building or its location, I cannot speculate further, nor can the OP until better information is received from the client.
Any operation that is running an old telecine machine like this (OP, what is this, a MkIII or something?
) is either doing something very specialized, or more likely trying to save money by using older equipment and that may well make the cost of bringing in 3-phase unattractive. The OP knows more about the overall situation that I do, though.
and i don't think the proper rewiring of the machine for 2 or 1 phase operation can be done in this timeframe due to the complexity of the existing installation inside the machine and the problem of accessing it and moving this really big , heavy and fragile heap around without crashing it .
For single phase, 120 volt operation, absolutely. Not only would that require a complete re-wire of the main power distribution in the machine, it would be an impractical thing to do. Why would you load down one side of your 120-N-120 with a single 60-90 amp load?
For split single phase, 120-N-120 operation, that remains to be seen. While I certainly understand the OP's hesitation about attempting any modifications, and appreciate the fact that this position may well not change, it is still an option, and the main distribution inside the machine does not have to be accessed or touched in any way to achieve.
If we assume that there are 7 power supplies on each of the three incoming phases, the OP would likely only have to be able to access the power input wires to three or four of those supplies that are on any
one of the three phases. New wiring could be brought directly out of the unit and connected externally to whichever phase had the lower loading. Cost? Maybe a couple hundred dollars in supplies, absolute maximum, plus the OP's time to get to those three or four supplies within the unit.
The rotary converter seems to be out of the question because of size / weight and noise issues .
Size, weight and noise are actually relatively minor concerns with this approach. I am more concerned with that kind of unit's ability to provide anywhere close to balanced voltages. Not only do they typically
NOT provide anywhere near a balanced voltage output, the mismatched
and time-variant loading of this unit complicates matters further. It will be virtually impossible to statically balance the capacitor arrangement to have anywhere near proper balanced power. What may work fine for a motor in a machine tool is not necessarily appropriate for a fragile telecine machine that expects clean power.
I also think that harmonic currents are going to be a huge issue with a rotary converter. Clipping of the wave is going to be severe unless the motor is huge and the cost of 25+ HP motors is not insignificant, nevermind the capacitor bank, etc.
A third option is a motor-generator set.
THIS has the potential to work well enough, provided the generator is sized appropriately to handle the horrible power factor without completely losing the tops of the waves.
Far superior from an electrical perspective than the rotary converter but, again, it is going to have to be vastly oversized from the nameplate rating for a resitive load to be able to handle capacitor-input rectifiers clean(ish)ly.
Gluing the 3 phases together to 1 phase is a nice idea
No, actually that is a
terrible idea.
... - i wonder how big the current impulse will be when you turn on 2 dozen big power supplies at the same time . . . 
and i'm not sure this nice setup with the 3 audio power amps will be able to handel the startup current either ( that is where the rotary converter will work pretty good ) 
A rotary converter would just have severe voltage drop for short time while the capacitors were charging. That isn't really a good or bad thing. A motor-genset would have the same issue, but that in and of itself wouldn't cause any problems. There are far bigger problems with a rotary converter.
As for the electronic APS-3720 AC power supply / regenerator doodad shown above, the available output current depends on what the original amplifier capabilities are and how they have been modified. The original specification for the design requirement given to me was for a 3-phase, 400 Hz, 115 volt, 20 ampere supply, later amended to be variable from approx 200-600 Hz for flexibility in testing once I offered them the option of it being variable.
My initial testing was done with a QSC RMX-2450, since I had one on hand anyway, and it worked so well that I have kept using that same circuit in subsequent units, even though I had initially thought it might need to be beefier. The current limiting is adjusted to start to come in at about 25A and short circuit protection trip at a bit over 30A, IIRC. I would have to check my notes. There will be distortion of the sine wave by that point, but it will do it, and there is a distortion indicator on the front panel of each phase's LPA to indicate that condition. I can start my 4 HP air compressor (wired for 120 instead of 240) off one phase. It starts slightly slower than it does on MAINS power (takes a couple cycles to get to speed) just like it does on a generator (even wired for 240), but it works fine.
Even if it
were an issue, this apparatus can easily ramp up the voltage to provide soft-start if required. I don't recall if I ever tried a 2400W+ load that was that "nasty" like a huge rectifier-capacitor battery charger load simulation, perhaps I should characterize that, but all sorts of DC power supplies have been run from the APS-3720.
The one time that there actually was an issue with powering a DC power supply was shortly after delivery of the first unit. It ended up being an interaction between the active power factor correction in the load (the DC power supply) and the feedback loop in the LPA setting up very high frequency oscillations in the LPA output stage and frying resistors in the snubber networks. A design change was made on my end, the units updated and the resistors replaced. There have been no subsequent issues powering any loads. (I tried everything I could think of for load testing, from air compressors to microwave ovens, universal motors like power tools and vacuum cleaners, overloaded it with halogen lights and boiling water in kettles.)
I might just have to set one up for more torture testing, though, now that this thread has piqued my interest.
In any case, even more robust amplifiers can be chosen if necessary. The modular topology of the whole apparatus makes alterations like that possible. The APS-3720 shown above is capable of pulling over 40A from each of the three phases on the AC input. Some of that goes to heat, obviously, but there is a
whole bunch of surge current available to run just about anything I could imagine to throw at it.
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