I've been trying to get my Growatt 3000 to charge my batteries, but I've run into some tricky issues. I'm living off-grid and originally used a Predator Whisper 2000 generator, which struggled and eventually overloaded after a year. So, I switched to a Predator 6500, assuming it would charge my batteries faster, but it hasn't made much difference, despite upgrading to a 30 amp setup. After three months, the generator started having backfiring and idling problems. I thought it might be a fuel filter issue, so I added some Seafoam, but it didn't help. Now, when the generator coughs, it stops charging because it can't maintain the 60 Hz threshold. I've tried flipping the breaker, but my Growatt just says there's no AC input, even though I can power a drill with the generator. Here are my questions: 1. Is this a generator issue or is my older Growatt on its last legs? 2. Does the Growatt need to be manually switched between 48V and 12V batteries? 3. Is there a way to set a minimum battery power level so the unit will turn off before it damages the batteries? 4. Do I need more input to charge a 48V battery at 46V compared to 50V?
1 Answer
Sounds like you might have a few issues happening here. For question 1, it could be a combination of the generator’s problems and the Growatt’s aging. If the generator struggles to maintain power, the Growatt won’t receive the stable input it needs to charge properly. For question 2, yes, the Growatt typically requires you to manually switch settings when changing between different battery voltages. Regarding question 3, there should be a low voltage cutoff setting in the Growatt settings that helps prevent damage to your batteries. Lastly, for your fourth question, yes, it does take more wattage to charge a nearly full battery because of the voltage drop during charging; a lower voltage means less power overall, assuming current stays constant.
Just to add to that, about the battery charging: imagine your battery as a container. If it's almost full, filling it up means you've got to work harder to get the last bit in, which can lead to lower efficiency.