Re: [RE-wrenches] String fuse blown

15, 2025 10:24 AM To: RE-wrenches Cc: Amos Post Subject: Re: [RE-wrenches] String fuse blown Hey all, To close the loop on this, I doesn’t look like its a “Power Save” setting as those are available on Grid-Tied FX’s. I went yesterday and confirmed that just Inverter #2 is pushing power when

Re: [RE-wrenches] String fuse blown

Hey all, To close the loop on this, I doesn’t look like its a “Power Save” setting as those are available on Grid-Tied FX’s. I went yesterday and confirmed that just Inverter #2 is pushing power when grid-tied ( 21A at 120V is what I tested at the time), however both start inverting (indicate

Re: [RE-wrenches] String fuse blown

Oh I forgot to mention the inverters are side x side on 2 individual Panels…. Amos Post Integrity Energy W 802.763.7023 C 802.291.2188 ienergyVT.com Facebook > On May 12, 2025, at 12:48 PM

Re: [RE-wrenches] String fuse blown

good point. For GT OB systems I have removed the side screens for better air flow and I’ve also taken the covers off and used external fans to cool them. They just were not designed to run anywhere near rated capacity for long periods of time, they don’t have enough air cooling. > On May 12,

Re: [RE-wrenches] String fuse blown

Is inverter 2 on top?  The top inverter in an Outback dual stack always runs hotter, because the heat from the bottom inverter is adding to its own heat.  I used to see that consistently cause board failures on the top inverter more often, if the whole system was running close to capacity. Ray

Re: [RE-wrenches] String fuse blown

UPDATE: So far so good and since replacing the fuse holder, fuse #3 has not blown again. ANOTHER ISSUE: Inverter 2 runs hotter than inverter 1. Reminder this is grid-tied system with 2-GVFX3648’s in series for 120/240V. The fan on inverter #2 had malfunctioned, but I was able to replace it

Re: [RE-wrenches] String fuse blown

Hi all, I decided to start with the simple stuff. While I don’t have a string curve tester (I should have one), yesterday I tested strings 1,2,3 individually under load. String 3 is the one that’s been blowing the fuse. I did not test strings 4-6 which are on a separate charge controller and

Re: [RE-wrenches] String fuse blown

Wrenches, Amos, blowing of a 15 amp fuse is not a ghost in the machine, it is an actual issue no way around it, shorted modules, shorted diodes, in most cases it's a home run, way back when USE-2 white wure was failing and would crack and break off mostly this would result in a GFI trip. The fuse i

Re: [RE-wrenches] String fuse blown

One time I had similar, but different problem: 1 Amp ground fault fuse consistently blowing, sometimes after 1 day sometimes after weeks/months. I tried everything - replaced home runs, checked VOC, VMP, swapped DC input into a different inverter, etc. it kept coming back to this one string. I che

Re: [RE-wrenches] String fuse blown

Hello Amos, Have you checked for voltage imbalance for each string? If you have a bad diode, that string may run low on voltage and be trying to send current toward the weak string (this is the reason you have these breakers). I'd run each string independently and see what Vmp is. If you are mi

Re: [RE-wrenches] String fuse blown

I would do 2 things. 1. If it’s string 3 fuse blowing, swap string 3 to another fuse. 2.  Replace the fuse holder, which is what I suspect is the issue. It’s a weak connection causing heat which is causing the fuse failure. JayOn Apr 11, 2025, at 8:07 AM, Amos Post via RE-wrenches wrote:Hi Wrench