Inverter seems to be working but batteries aren't

Now Batterybhai is India's first online multi-brand battery store in India, having a complete range of 100% genuine batteries from brands like Amaron, SF Sonic, Exide, Okaya, MtekPower, Sukam, DigiPower and AC Delco. I always buy batteries and other electronic products from this store, It prices are cheaper than other stores and provides free home delivery & installation. I suggest to all my friends and customer who wants to buy batteries and inverter must visit this store.

not knowing model number its impossible for me to determine if your inverter has a battery charger , not all do some require a external one , most charge off aux engine alternator this same engine also makes compressed air and hydraulic power for controls and steering , mid size boats use one engine for all this plus main drive , larger ones use a separate engine for these functions (safer)

It sounds like a bad battery mine did the same but it was a much larger unit changed the house AGM Batteries and works perfectly

check the fuses

Is the inverter configured for correct type of batteries? Did inverter come with temperature sensor what should be connected to battery to prevent overheating? Are batteries in good condition, acid level, clean posts etc?

If you overloaded your inverter you may have burned out internal circuitry. It's not hard to exceede 450 watts. I don't think there is any way to repair your inverter that won't cost more than a new one. Have you checked to see if there is any overload protection on this unit I had one of these several years ago and I seem to remember ther being black button on the back that was a reset. Hope this helps. Thanks

Inverter run on batteries sir, and if these batteries are not charged, the run time {the number of hours it will work} reduces.
S0, you will need to connect the inverter to a power source.Theses will allow your batteries to be charged and enable it to run for a long period of time.
Make sure your batteries are still OK.i.e working properly

it is possible that you batteries are bad, if you have used it for over a year you will need to replace it with new ones

It's quite possible that you are charging your batteries with a "smart charger." The problem with some smart chargers is that when a battery is drained below a certain voltage, the charger assumes the battery is a lost cause and stops trying to charge it. You may have to get a cheap "dumb" charger to bring the batteries up to a reasonable voltage before turning things back over to the smart charger.