tmw
Member
The attached photo is the fuse that goes between my solar controller and the house battery from my 320 watt array. I was a little frightened to find it and I only found it because I noticed the controller screen was dark while winterizing. I thought it was a bad fuse or fuse holder. For fear of burning down the boat yard, I disconnected the solar array.
Last winter I changed the controller from a PMW to a MPPT. I was comparing the data logs to see the difference and noticed that I would commonly get 22-23 amps of charging current at peak times, mid summer. I'm guessing that the high current was enough to get it hot and slow cook the fuse and holder but never enough to blow the 25 amp fuse.
Either way, I'm changing it over to a circuit breaker. The math says I shouldn't get that much more power out of the panels. The wiring is either 8 or 10 gauge. I'll have to check but I'm wondering if I should just go to a 30 amp breaker with 10 gauge cable and leave it at that or change the cable to 8 gauge and go higher.
Thanks
Last winter I changed the controller from a PMW to a MPPT. I was comparing the data logs to see the difference and noticed that I would commonly get 22-23 amps of charging current at peak times, mid summer. I'm guessing that the high current was enough to get it hot and slow cook the fuse and holder but never enough to blow the 25 amp fuse.
Either way, I'm changing it over to a circuit breaker. The math says I shouldn't get that much more power out of the panels. The wiring is either 8 or 10 gauge. I'll have to check but I'm wondering if I should just go to a 30 amp breaker with 10 gauge cable and leave it at that or change the cable to 8 gauge and go higher.
Thanks
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