I will try to be as articulate at possible. I have a 3kva five star invertor, connected to 2 200ah batteries in series and 2 330w panels.

Yesterday I was away and something must have happened and now the invertor, when the battery depletes(I run a small fridge, load always 0W except on startup which pulls 170ishW usually lasts overnight but weather has been bad over the past few days)

1. won't go on standby mode, it keeps powering up, then down, repeatedly every 5 seconds or so even when I turn it off.

2. It won't show that the solar panels are charging, but they are charging the batteries cause today I used it, there is just no arrow showing from panel icon to battery. 

3. So even when it keeps starting and stopping it is charging, then I have to manually switch it on and it continues working and charging per normal

4. I can't afford to have it fixed so is there something I can do that could fix either the not showing charging thing or the not staying off. The beeping is driving me insane, but I can't disconnect because I need the electricity. Its exam time and no eskom power out here.

11 hours ago, Five star one star said:

1. won't go on standby mode, it keeps powering up, then down, repeatedly every 5 seconds or so even when I turn it off.

That sounds like an unusual problem with the main power supply.

11 hours ago, Five star one star said:

is there something I can do that could fix either the not showing charging thing

That's pretty weird. I can't explain that.

Do you see the battery voltage go up during the day?

Does the green CHG light show charging (flashing) for some hours then float charging (on, not flashing) (assuming enough sunlight), then off at night?

11 hours ago, Five star one star said:

I have to manually switch it on and it continues working and charging per normal

So it powers the fridge and any other loads when the switch is on?

11 hours ago, Five star one star said:

is there something I can do that could fix either the not showing charging thing or the not staying off.

Chewing gum or Blu-tack over the beeper? It's on the control board (smallish daughter board plugged into the main board) inside the inverter.

If it really is charging, then the lack of a charging indicator could perhaps just be ignored?