MN3548DIY BatOverCurrHW

[sungrip]

Getting a persistent flashing red Fault LED and fault code 05 - Battery Overcurrent hardware protection regardless of trying different batteries.

[Wizbandit]

The internal DC to DC power converter section is busted.  Causes:
Not enough Ah of battery, the DIY3548 needs 300 to 500Ah of battery
Battery cables too small gauge or too long.
Load(s) with motors that have big startup currents, A/C units, water pumps, air compressors...

[sungrip]

Thanks. 
No load has ever been connected to this inverter.  I'm getting the error with no load. 

Regarding battery cable gauge and length, I'm testing with 4' 4AWG to a fuse and 7' 2AWG to the battery.

The test battery is a 120Ah 48V LFP

[Saggys]

I also have a 3548 with #2 awg and a 200ah LiFeP04 battery with no issues. I believe the manual states a 100ah minimum.