It's not clear to me what time shift is appropriate. I downloaded NSRDB data and did not select "convert UTC to local time". I then used the .MEF file which was posted by solarguru on 10/17/16 which included a shift of 5 hours. My site is located in UTC-5. I'm getting errors that "GlobHor" data is undefined, and also that my time seems mismatched. Does anyone know what the most appropriate way is to treat NSRDB data, specifically PSM v3?
The result of the time shift is revealed after the conversion has happened. After complete, a box will come up asking for you to inspect the data, click yes, and select "check data quality" tab to see how far off you are, and if adjustment is needed.
If your glob Hor is undefined, it might mean that depending on the variables you imported from NREL, it may not be matching up with the MEF file I provided. You will need to update the MEF to point to the correct columns. When I download PSMv3, I only download the variables I need for PVsyst (GlobHor, DiffHor, Tamb, Wspd) + DNI. When I download a UTC-5 site, and I check "convert to local time" when download NREL PSM, a time shift of 5 hours generally works. If you did not check convert UTC to local time, you may need to do something different. Since I haven't done it with that unchecked, I cant provide any help there.