I have been looking at a lot of wiring diagrams as well as the Classic Install Manual.
I think I just had and Ah Ha moment...
this diagram (for non integrated GFP) shows the ground from the CB as WHITE.
http://www.midnitesolar.com/pdfs/Charge_control_wiringGFP.pdf
Earlier I remember seeing in the Cl Manual that a white PV Neg connected, Fig 12 and 14 here:
http://www.midnitesolar.com/pdfs/classicManual.pdf
at the time I surmised that this was because of the connection to the common AC & DC grounding bus bar but now I am wondering as link 1 shows WHITE from the GFP to the Batt (-) buss...??
And on page 21
If the internal grounding jumper is installed in a Classic, the battery negative and DC source negative must not be connected to the system grounding conductor anywhere in the system
Can someone please explain this use of WHITE wire. thanks
OR is this all mush brain thinking?
Yes the small breaker 0.5 or 1 amp is intended to physically bond DC negative to earth ground. This way if there is a Ground fault of sufficient amperage it trips that breaker and opens the paralleled breaker thus stopping the charging. So by nature one side of the breaker is green wire (Ground) the other is white wire (DC negative)
Ryan
Sorry Ryan, I'm a bit slow getting it, but is this the correct interpretation of link 1, WHEN using the built-in GFP? (Link 1 shows the external 1 amp CB)
Use a white (PV Neg) wire to connect the Classic to the Battery /DC neg buss bar.
And the Neg grounding is done internally to/by the built-in GFP when a fault occurs.
I think I am getting system grounding and Lightning grounding confused, plodding through that scenario:
If an EMP occurs the SPD 300 will divert from PV (+) to ground, hopefully saving the install...
thanks
It truly hasn't sunk in yet but I think it is clearer...
Yes basically what the Classic does is this:
DC negative bus internally ---> 2 pin Jumper ---> 0.5 amp self healing fuse ----> Casting/Earth ground
So as you see there is a 0.5 Amp self healing fuse that (If the jumper is installed) bonds the DC negative bus to the Casting.
The rest of the earth ground system needs to be run as normal.
Ryan