I used one like this:
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You may have to shop around for one with larger amp rating or use two since you have two inverters. You could easily use two with the batrium (assuming you have the expansion board). You might want to see how your inverters handle being disconnected from the battery while under load.
If you get a shunt trip, make sure it's 24v (or if you can find one that will work with battery voltage). There are a few youtubes on wiring like
. I went the route like this guy did with a 48v->24v converter which powers the batrium and provides power for the shunt trip. The Batrium will run on up to 65 v and you can tap your battery for 24v for the shunt, but I didn't know if I would add any other gadgets like fans and 24v is common. So I went with a converter.