Is charge controller available for 120V DC system?

hmm, check with a company called solar converters, they do custom stuff. 

the bigger question is do you have a 120v nominal pv array?

james
altE staff

huh, what are you running, an exeltech?  i know they have inverters that can run at that voltage.  the reason there are not more high voltage battery systems is that the code prevents banks beyond 48v nominal in residential systems.

so if you do have a 120v nominal array, i dont know of any controllers, but solar converters does do customer gear.  the problem as i understand is that the internal components cant handle those voltages, specifically the FETs i think.  you are looking at 2oo volts open circuit before temp derations, so that may mean no go for a controller like that, but i dont know, it is pushing the boundaries of my knowledge.

james
altE staff

A PV array of 40,000 watts at 120 vdc nominal?
Thats still 333.33 amps without the UL/NEC 156%!
If I multiply that by 4 hours of equivalent full rated charge we are looking at 1,333.32 amp hours at 120 vdc nominal!
If I multiply that by a factor of 5 to size a battery bank, thats 6,666.6 amp hours at 120 vdc nominal battery bank!

Industrial motor controls use magnetic starters. For example; a 120 vac single phase, less than 1 amp draw coil, is used to "pull in" a starter that connects a higher voltage and amperage motor circuit like say, 480 vac 3 phase at 100 amps. An automobile starter works on this same principle only they are all they same voltage, just higher cranking amps. Old timey cars and trucks used to have something like the old foot operated headlight high/low switch only the foot operated stater button was normally open and momentary and it connected the full amperage from the battery to the starter when depressed. The key switch simply turned on the ignition. But enough of that.
If one could build a sensor that could read 120vdc nominal battery voltage as compared to 120 vdc nominal PV array voltage and make the high/low setting field selectable and that could "pull in" or "drop out" several contactors of a higher amperage rating in accordance... Your problem would be solved. This would in effect be a simple on/off charge controller technology similar to the Trace C30's. One problem would be that at higher dc amperages, the contacts have a greater tendency to weld together. This might be overcome by reducing the amprage with several sub-arrays and multiple contactors. If one does weld together, enough of the other contactors could open there by reducing the over all charge. As with any system of this nature redundancies and alarms may be necessary. PLC's would be a nice touch. Just an idea.

This is the closest thing I could find to what you are seeking that is, more or less, "off the shelf." It actually does more than what you may need but as James pointed out, a custom piece may have to be built. Good luck!   
http://www.tmiestore.co.in/newpdf/Solar/SolarChargeControllers/MPR9400.pdf

http://www.tmiestore.co.in/solar.htm

Ok, I was a little confused at first by how you were asking about 120 vdc PV charge controllers on something such as the Alt-E Store community forums but I let it go and went with the flow. Now your asking about integrated components for large scale photovoltaic power plants. That along with a "guy" that wants to remain anonymous has got my "spidey senses tingling" if you catch my drift. 
I do not assume to speak for the Alt-E Store but I would like to say, it would seem to me that the Alt-E Store is primarily residential and commercial PV system oriented. More so than utility scale PV power production anyway. Please forgive me Alt-E Store if I have crossed a line here.
There are places that cater to the utility scale PV systems operator. Perhaps you can find what you are seeking at one or more of these sites? Or at least links to other sites.
http://www.solarplaza.com/home/
http://energy.sourceguides.com/index.shtml
http://www.solarelectricpower.org/
http://www.pvworld.com/index.html
http://solarpowerlimited.com/

Personally, I would think that a more efficient way of storing power from a utility scale PV plant for night time use would be hydrogen instead of lead acid batteries.
http://www.satcon.com/

The following news clip is almost a year old but maybe you could find one near you and arrange a tour? http://earth2tech.com/2008/08/27/solar-map-over-30-utility-scale-solar-plants-in-the-us/

I hope that something here helps "Tech Guy."

I found this on another discussion board so...

http://www.fieldlines.com/story/2008/10/1/13567/9879

If its true, you would still need what, about 12 of them?
I tried to download and read the manual myself from Outback but it was corrupted.