This is caused by low intermediate circuit DC voltage. This can be caused by a missing supply voltage phase from a blown fuse or faulty isolator or contactor or internal rectifier bridge fault or simply low mains voltage. POSSIBLE FIXES: Check mains supply and fuses. What exact is error 52 (bus voltage too low) on MPP Solar LVX 6048? I've installed my LVX-6048 with 4kW panels (8S2P 250W) and split-phase 240V AC input. As I'm in Mexico, UL compliancy is not required for my home here (yet), so I'm exporting energy to the grid. Everything works well except when. Low-voltage alarms usually mean DC input fell below threshold—most often under load (voltage sag), not at rest. POSSIBLE FIXES: Turn the overvoltage controller is. Under normal circumstances, the DC bus voltage should be within a certain range of the rated DC voltage of the inverter (usually ±10%).
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