Switch between AC (Grid Power) and DC (Solar Panel) when DC voltage reaches 200v

Good Afternoon,
My boss and I have been pondering a problem and we aren't sure what equipment would be needed. We have a submersible pump in a well that can take either AC or DC voltage. Right now there is a manual switch that must be turned each day to take the pump off the Grid and put it on the power output from a set of Solar Panels. We'd like this to be an automated process where a piece of equipment senses when the DC voltage output from the panel reaches 200v and automatically switches off the AC grid power and goes to the DC voltage to run the pump motor. Any help would be appreciated.
Thanks,

I have in mind a relay or a double-relays just as easy way. The first relay for 200 V that enable another one for AC grid.  The problem would be for the first...

HiProbably the simplest solution would be to use a Low Voltage Drop Out Relay.  Depending on your application and chosen relay you may also need it to operate a changeover contactor (big relay).If you do a search on any of the major suppliers sites you should find something. As an example http://www.farnell.com/datasheets/1854396.pdf for a SPDT low/high relay.Please be careful when working with "mains"electricity and if unsure of anything please refer to someone qualified.
Hope this helps.
Regards

Hi,So you need a controller( PLC or embedded board) that will sense the DC power and change the switch AC to DC accordingly.  You can make your own embedded board or you can choose low-cost PLC from the market. I would like to suggest i-trilogy embedded PLC which is low cost and quality is good, I have develope many solar controllers by this PLC and working flawlessly almost 3 years without any issue. To switching AC-DC or DC-AC  you need a changeover relay. In the market, there are many manufacturers but  I like ABB. To drive this changeover relay you need a pilot relay you can choose from OMRON.  Regards,prayuktibid

[User comment deleted]

One problem you will get is that the 200V on the panels will
drop a lot as soon as the pump is connected so any relay may chatter on and
off.

 

Also I find that the open circuit V of panels is high even with
little sun. So you may find that the 200V you think is going adequately power the pump actually
does not once the pump is connected. One way around all this is to use a changeover
relay that adds a high dummy load to the panels when not connected to the pump.
Thus the loaded panel voltage more closely determines if there is enough power
there to feed the pump.