|03-01-14, 08:33 PM||#1|
Join Date: Dec 2012
Location: Cave City Kentucky
Thanked 7 Times in 4 Posts
Using a solar system as a generator (to be code compliant)
I have an Outback GVFX inverter which is a Grid Interactive Unit, It has a bi-directional (AC In circuit), which allows the user to sell PV output to the grid. If the grid goes down it will drop the connection to the grid and begin to power a separate AC out circuit that will power user determined critical loads. I would like this system to be code compliant.
I understand that the GVFX inverter has a built in transfer switch to enable it to switch from it's by-directional (AC in) circuit to (AC out) in the event of a power outage. Rather than use a sub panel for critical 120v loads, I would like to use house's service panel ONLY, for connecting to the inverter's AC hot out circuit.
I plan on using a generator interlock mechanism that is available for the new breaker box I am having installed to replace the existing house box which makes it impossible for the main to remain switched on in order for the house panel to be back fed by the other breaker which is interlocked to the main.
The interlock kit has a 50 amp 240 volt breaker for back-feeding. I would like to substitute a 30 amp 120 volt breaker in it's place, but if need be I also have an Outback PSX 240 auto transformer I could use to bump up the GVFX's output to 240 volts so as not to be guilty of altering the interlock kit's original design, which may cause it not to be code compliant. This would also eliminate the need of keeping all of the 120 volt circuits on one leg of the breaker box seeing that it would power both legs.
Of course I know that I would need to switch off all of the 240 volt breakers before operating the interlock function, and manage my 120 volt loads to stay within the inverter's 30 amp capability.
All of the power equipment is located in a shed and the shed will have it's own 240 volt service from the house breaker box. I understand that if the interlock breakers are operated so that the main is off the inverter will not know when the power comes back on.
This whole set-up basically allows using the batteries and inverter as a generator. From looking at the various interlock kits I don't see why it would not be a legal setup. The only difference from a generator is the GVFX's bi-directional line (AC In) which will lose its connection when the interlock breakers are switched to generator positions.
Anyone versed in Solar grid tied / battery backup systems that can comment?
Last edited by verdigo; 03-01-14 at 09:23 PM..