What bad thing happens if I do this?

[Freep]

This is a camper scenario where an inverter, solar and LFP battery have been added. There are two automatic transfer switches on the AC side of things that keep shore, generator and inverter power separate. However, there is only a circuit breaker that keeps the inverter from powering up the converter, which in turn charges the battery.

What bad thing happens if the breaker is not off and the inverter is on, thus creating a little loop? Will it just run the battery down, create a fault in the inverter, cause a fire, rip a hole in the space time continuum, what?

 

[gnubie]

It'd depend on the inverter and converter being properly isolated devices. If they are, ie there is no DC path through things, it will just run the battery down. If everything isn't isolated, you will rip a hole in the space time continuum when your inverter and/or converter blow up / catch fire / etc.

 

[John Frum]

If the inverter and converter are connected to the same dc power domain the inverter will power the converter which will power the inverter.
It should drain the battery at the converters dc rating plus ~15% overhead for the ac to dc conversion and another ~15% for the dc to ac conversion.

 

[Freep]

The converter dumps DC straight into the DC distribution panel. It's a PD4045. Eventually that DC makes its way back to the battery.

 

[John Frum]

The converter dumps DC straight into the DC distribution panel. It's a PD4045. Eventually that DC makes its way back to the battery.

and the battery powers the inverter.

 

[Freep]

I guess it's time to get a little SPST NC relay to close that path off when the inverter powers up. Something like this

https://smile.amazon.com/American-Zettler-Power-120VAC-AZ2280-1C-120A/dp/B07587NZTC

Unless someone has a better idea?

 

[HaldorEE]

The inverter should be smart enough to know if you have shore power connected or not.

My Victron Multiplus deals with this situation automatically. It even switches the ground/neutral jumper in and out depending on if shore power is connected or not.

This is a reason to use a combination inverter/ charger instead of separate inverters and chargers.

 

[erik.calco]

If you capture it on video, and there is smoke, you could make enough to upgrade your system.