Steelart99
New Member
@EG4TechSolutionsTeam
I had a couple of spikes of grid imports with a weird hum/rattle noise associated with them. Is there a reason for this?
I have only two types of loads that are short duration with fairly high power usage: Deep well pump starting and furnace blower cycling. Well pump power usage (blue down arrows) is higher than the blower. In the image below (from yesterday) of my system performance, there are two times where the well pump start seems to drive brief grid imports (red up arrows). This is NOT typical but it has happened rarely in the past. Strangely, when this occurs I will hear a fairly loud humming/rattling coming from the inverter (or battery?) for about 20-30 seconds. There is not enough time for me to note it happening and get downstairs to my garage to video what the inverter and/or battery might be doing as it is occurring. I have also heard this humming/rattle noise when my system has automatically used grid input to charge my battery when it hits 20% SOC (insufficient PV), with the noise occurring upon grid input cycling OFF. Note: I have a single EG4 Wallmount battery.
I'm guessing that the brief grid power demand might be due to high starting current demand of the well pump which doesn't actually show in the data.
Is the noise a normal inverter symptom of grid power shutting off? What else could be causing this noise?

I had a couple of spikes of grid imports with a weird hum/rattle noise associated with them. Is there a reason for this?
I have only two types of loads that are short duration with fairly high power usage: Deep well pump starting and furnace blower cycling. Well pump power usage (blue down arrows) is higher than the blower. In the image below (from yesterday) of my system performance, there are two times where the well pump start seems to drive brief grid imports (red up arrows). This is NOT typical but it has happened rarely in the past. Strangely, when this occurs I will hear a fairly loud humming/rattling coming from the inverter (or battery?) for about 20-30 seconds. There is not enough time for me to note it happening and get downstairs to my garage to video what the inverter and/or battery might be doing as it is occurring. I have also heard this humming/rattle noise when my system has automatically used grid input to charge my battery when it hits 20% SOC (insufficient PV), with the noise occurring upon grid input cycling OFF. Note: I have a single EG4 Wallmount battery.
I'm guessing that the brief grid power demand might be due to high starting current demand of the well pump which doesn't actually show in the data.
Is the noise a normal inverter symptom of grid power shutting off? What else could be causing this noise?

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