hi gary, i gotta agree with john. there are two reasons the rv inverters are so expensive (AND HEAVY). 1. the ability to handle surge wattage requirements while still delivering high quality power (steady voltage, phase and current). 2. the charging system that they are as well.
i am an EE, and my son in law is a phd in power engineering and he had the same thoughts. that the cheapo inverter will likely not be of enough size to handle a compressor startup (the locked rotor amps or LRA) and still deliver the quality of power required to not dramatically shorten the life of the compressor.
when i rebuilt my freedom 458, i also re-wired it correctly (common for aftermarket installs). it is the same modified sine wave inverter you have. i put in a circuit to run my microwave. the microwave works, but dreadfully. meaning it sounds strange and is not at full power, but it does work. some microwaves klystrons require high quality power more than others and the sharp convection microwaves we have are one of those.
i don't use it that way very often, but if i did and had to replace he microwave that is a little easier than he fridge to replace....
so, i would spend some time with any non rv inverter making sure it will really do the job.
the other thing is that i am not sure you can use the same batteries to power a second inverter. so you would need to check that out. or you would need another bank of batteries.
you can calculate how long your batteries will power an invertor with specific current draws. a fridge compressor really sucks the power...
so, caution rules on this.
tom
|