Post by Admin on Sept 24, 2018 13:41:56 GMT
Jun 5, 2018 15:29:57 GMT @jon said:
I have a Renogy 600 (6x100) Watt RV package bought over a year ago and just now installing. It came with one 20A fuse which we installed between the panels and the 12V 60A Commander MPPT Controller. At some point the system went into LVD and we found the fuse blown and a loose battery connection. Once reconnected the Controller went into Boost mode showing 27.3 A. The fuse at this point was very hot!! I'm wondering about the heat build up, whether this would cause the fuse to blow, and whether I should consider additional fuses on the PV panels which are wired parallel? The PV wires between the PV and the controller are about 14 ft long and the wire between the controller and the batteries is 8 gauge, about 6 ft long.
You need a 60a fuse..... A 20a can't take it it's to much voltage... That's the same CC that I have...
Jun 5, 2018 16:02:16 GMT @jon said:
Thanks, certainly makes sense. I'm wondering why the 20A was supplied with the kit???
Jun 5, 2018 17:47:23 GMT @rabird said:
ideally you would fuse each panel and then the combined set of 6, this is on the panel to controller side.
www.windynation.com/jzv/inf/how-properly-fuse-solar-pv-system
Jun 6, 2018 13:06:10 GMT @rabird said:
Input
in parallel, 600watts/17v = 35A, use 8g or larger from the combined panels to controller, 40+A fuse for the combined input, 10-15A on each panel (see max fuse on back sticker).
All in series, 600watts/ =6A, can use much smaller wire, no fuse required (any short will be limited to 6A).
Output, 600/13 = 46A use 50-60A fuse 8g may be a bit small.
A 20A fuse on the input side is more than enough for series of 6A
Your 27A output in boost was ~20A on the input side due to parallel connected panels.