Do the VYCON units generate any physical heat (I've never known anyone to have one)?
A little bit, not that much.
Do they make much noise in operation (when called upon for duty), as compared to just sitting there? Are there transfer switches involved with the units, or are they constantly on/in-line, like a double-conversion UPS. BTW, are your Eaton UPS' considered double-conversion? Kelly A, I applaud you for so much devotion and attention you pay to (your) maintaining clean and uninterruptible AC. That's like an engineers dream come true.
Think of flywheel UPS's as a motor-generator. Utility power runs an electrical motor, which spins a perfectly balanced flywheel supported by magnetically levitated bearings. Connected to the flywheel is a generator. (technically an alternator) That generator provides 480 3 phase AC power at 60Hz to run the critical gear connected to the UPS. The motor/generator is enclosed in a large vacuum chamber to eliminate atmospheric resistance to the spinning flywheel/levitating bearings or other spinning components. Running in a vacuum also eliminates concerns of humidity, condensation, pollution, or drying-out of components caused by our atmosphere. Heat from the motor and generator are conducted in free space to the vacuum chamber housing, which is shaped like a giant heat sink and carried away from the cabinet via fans. The fans drawing hot air off the vacuum chamber make most of the noise.
Since I was discussing lightning, have any of your units (Eaton UPS', or VYCON's) ever sustained any lightning damage, and is that something you have to consider with these units?
None with the VYCON units. The motor of the motor-generator side connected to the utility power has silicone avalanche diodes to protect damage to the motor(s). It would take quite the surge to harm the motor part. Both the VYCON's and EATON's have logged some pretty wicked surges, but have always shrugged it off.
Is it safe to assume you have separate dedicated AC feeds to your in-house electronics from the VYCON's and the Eaton UPS'? And if that is the case, can one generator then feed both of those routes?
The way it is now, the VYCON's and EATON UPS's have different loads. We're scheduled to replace the EATON's next year, and have talked about tying the two UPS systems together, which in theory would create an additional layer of backup. I've been leaning to not go that route, instead just replacing the EATON UPS's with a newer model. My father used to say:
'If it works, don't fix it'-words ring in my head when we have that discussion. Tying the two systems together add additional complexity.
We have one Caterpillar 2.5MW diesel generator and a Kohler 500kW that backs up the entire building. When the power goes out, the CAT takes the entire building load, including powering all the UPS's. It essentially becomes the utility.
Roughly speaking, how many batteries are incorporated in a 1 MW UPS system?
I believe each of the EATON's have something like 38 batteries?
Are they all hot swappable? Are all batteries replaced at once? Sorry for all of the questions, but it sounds like you have a very unique setup.
When it comes to these big commercial UPS's, battery life and replacement depends on when the batteries were installed and how an individual battery degrades. As a rule, you don't want to get into a position where you have to replace all the batteries at once, because that requires bypassing the UPS entirely. We have a service tech come in two times a year and check the status of the individual batteries and overall condition. If one or more batteries are showing signs of degradation, they get replaced. I can also log into the UI from my desk at any time to see how the batteries are performing, or walk downstairs and look at it on the individual touchscreen, right on the UPS.