Power jack 3500w inverter power problems.

The water has shorted it out. Water and electronics is a BAD mix.

OLP (Overload protection indicator): Indicates the inverter will shut down due to a short circuit or overload protection. the inverter cools down, the indicator will turn off automatically.
Feb 14, 2023

Pure Sine Wave (ISW) Inverters: Error Codes - Go Power!

gopowersolar.com https://support.gopowersolar.com > article > 241-pure-si...

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please check if all attached connection are tight .Sometimes loose wire connection also causes fuse blow

I assume your not using a pure sine wave inverter. A lot of electronic devices won't work on a lower cost inverter (modified sine wave) that has a square sine wave, either invest in a true sine wave inverter or don't run sensitive electronic equipment, I'm somewhat surprised you didn't damage the circuit board in the microwave...Below is a link of a inverter that would work if you want to spend the money for one.
2500W 5000 Watt Power Inverter Pure Sine Wave 12V dc 110V 120V ac LCD...

Without knowing make or model other than 600 Watts and pure sine output:
http://www.donrowe.com/user_guides/samlex/ssw_series.pdf
is for a series of pure sine inverters, yours should be similar enough to the 600 Watt version to be of practical use.

Hi , i'm sorry but i dont really understand your question , assuming the current draw is around 45 amps then 2 /0 GA is fine , just keep your leads from your panel nice and short , the connection kits are sold by sunforce and there plenty of suitable connectors on the market
example link below
http://www.globalepower.com/Datasheets/BatteryConnectors/BatteryGlobal.pdf

ur battery exp.(if it is 3 or 4 year old)
ur inverter is over load

I highly suggest you invest in a good quality inverter. For most equipment either pure or modified sine wave is fine. I would suggest you install a line conditioner after a UPS for any computer products. The line conditioner stabilizes the voltage much more closely than a UPS will.
As far as building your own, I've taken apart a lot of UPS models which have a DC-AC converter in them and they are filled with lots of heavy heat sinks, transistors, resistors, capacitors, etc. You can usually find these very cheap since the batteries die but the converter is fine. Check the input voltage of the original unit and start from there to make one easily that has everything already assembled with minor modifications.

pure sine wave will be the best option ,but note it is not very possible to get a pure sine wave type

Had a similar problem with the same inverter BUT to include a failing cooling fan.

NOTE:
Take it back and get your money back as soon as possible.

Replaced it with a pure sine inverter 1500 watt that is kicking **** 24 seven days a week on my solar / wind power system.

RECOMENDATIONS:

UPGRADE.

Hope this tip helps.

R/
David

I would not do this, you really need a pure sine wave inverter to guarantee the safety of your CPAP machine. At the price they are selling this device it could not be pure sine wave. 150W pure sine wave would be $70-$100.